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Section I: - Core Java ProgrammingAssignment No.: 1 Date: 02-01-2012

Title: Implementation of Arithmetic Operations

AIM: Write a program to implement arithmetic operationsA. Use static inputB. Take input from command prompt (Use wrapper class)

OBJECTIVE: To expose the concepts of java program, various data types and conversion

THEORY:

Basics of Java

Java was conceived by James Gosling, Patrick Naughton, Chris Warth, Ed Frank, andMike Sheridan at Sun Microsystems, Inc. in 1991. It took 18 months to develop thefirst working version. This language was initially called “Oak” but was renamed “Java”in 1995. Object-oriented programming is at the core of Java. In fact, all Java programs areobject oriented—this isn’t an option the way that it is in C++, for example. OOP is sointegral to Java that you must understand its basic principles before you can write evensimple Java programs.

Data types, Variables

Fig 1 “Summary of Primitive Data Types”

Table 1 “Data types, their ranges & corresponding wrapper classes”DataType

Width(bits)

Minimum Value, Maximum Value WrapperClass

boolean NotApplicable

true, false (no ordering implied) Boolean

Byte 8 -27 to 2 7-1 ByteShort 16 -215 to 2 15-1 Short

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Char 16 0x0, 0xffff CharacterInt 32 -231 to 2 31-1 IntegerLong 64 -263 to 2 63-1 Long

Float 32 ±1.40129846432481707e-45f,±3.402823476638528860e+38f

Float

double 64 \'b14.94065645841246544e-324,\'b11.79769313486231570e+308

Double

Variable Declarations

A variable stores a value of a particular type. A variable has a name, a type, anda value associated with it. In Java, variables can only store values of primitive datatypes and references to objects. Variables that store references to objects are calledreference variables.

Declaring and Initializing Variables

Variable declarations are used to specify the type and the name of variables. Thisimplicitly determines their memory allocation and the values that can be stored inthem. We show some examples of declaring variables that can store primitivevalues:

char a, b, c; // a, b and c are variables of type character

A declaration can also include initialization code to specify an appropriate initialvalue for the variable:int i = 10; // i is an int variable with initial value 10.

Object Reference Variables

An object reference is a value that denotes an object in Java. Such reference values canbe stored in variables and used to manipulate the object denoted by the reference value. Avariable declaration that specifies a reference type (i.e., a class, an array, or an interfacename) declares an object reference variable. Analogous to the declaration of variablesof primitive data types, the simplest form of reference variable declaration onlyspecifies the name and the reference type. The declaration determines what objects areference variable can denote. Before we can use a reference variable to manipulate anobject, it must be declared and initialized with the reference value of the object.

Pizza yummyPizza; // Variable yummyPizza can reference objects of class

It is important to note that the declarations above do not create any objects of classPizza. The declarations only create variables that can store references to objects of thisclass. A declaration can also include an initialize to create an object whose reference canbe assigned to the reference variable:

Pizza yummyPizza = new Pizza("Hot&Spicy"); // Declaration with initializer.

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Setting Environment Variable From Command Prompt

E:\Zeal\Second Sem\TE IT\Java Programs>set path=%path%;C:\Program Files (x86)\Java\jdk1.6.0_01\binE:\Zeal\Second Sem\TE IT\Java Programs>

First Java Program:-

/* First java program, call this file as “Example.java” */ class Example {

public static void main(String args[]) { System.out.println("Hello World");

}}

The main Method

The Java interpreter executes a method called main in the class specified on the command line. Any class can have a main() method, but only the main() method ofthe class specified to the Java interpreter is executed to start a Java application. Themain() method must have public accessibility so that the interpreter can call it. It is astatic method belonging to the class, so that no object of the class is required to start theexecution. It does not return a value, that is, it is declared void. It always has an array ofString objects as its only formal parameter. This array contains any arguments passed tothe program on the command line. All this adds up to the following definition of themain() method:

public static void main(String args[]) {// ….}

The above requirements do not exclude specification of additional modifiers or anythrows clause The main() method can also be overloaded like any other method The Javainterpreter ensures that the main() method, that complies with the above definition isthe starting point of the program execution.

Compiling and Interpreting a Java Program From Windows Command Prompt

E:\Zeal\Second Sem\TE IT\Java Programs>javac Example.javaE:\Zeal\Second Sem\TE IT\Java Programs>java ExampleHello WorldE:\Zeal\Second Sem\TE IT\Java Programs>

Wrapper Classes

Wrapper class is a wrapper around a primitive data type. It represents primitive data types in their corresponding class instances e.g. a boolean data type can be represented as a Boolean class instance. All of the primitive wrapper classes in Java are immutable i.e. once assigned a value to a wrapper class instance cannot be changed further.

Wrapper Classes are used broadly with Collection classes in the java.util package and with the classes in the java.lang.reflect reflection package. Table 1 above shows primitive types

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and their corresponding wrapper classes.

Features of the Wrapper Classes

Some of the sound features maintained by the Wrapper Classes are as under :

All the methods of the wrapper classes are static.

The Wrapper class does not contain constructors.

Once a value is assigned to a wrapper class instance it can not be changed, anymore.

Wrapper Classes: Methods There are some of the methods of the Wrapper class which are used to manipulate the data. Few of them are given below:

1. add(int, Object): inserts an element at the specified position.

2. add(Object): inserts an object at the end of a list.

3. addAll(ArrayList): inserts an array list of objects to another list.

4. get(): retrieves the elements contained with in an ArrayList object.

5. Integer.toBinaryString(): converts the Integer type object to a String object.

6. size(): gets the dynamic capacity of a list.

7. remove(): removes an element from a particular position specified by a index value.

8. set(int, Object): replaces an element at the position specified by a index value.

FAQs:1. What's the difference between J2SDK 1.5 and J2SDK 5.0?2. What environment variables do I need to set on my machine in order to be able torun Java programs?3. Do I need to import java.lang package any time? Why?4. What is the difference between declaring a variable and defining a variable?5. What is static in java?6. What if I write static public void instead of public static void?7. Can a .java file contain more than one java classes?8. Is String a primitive data type in Java?9. Is main a keyword in Java?10. Is next a keyword in Java?11. Is delete a keyword in Java?12. Is exit a keyword in Java?

CONCLUSION:Students should write down their own conclusion here.

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Assignment No.: 2 Date: 09-01-2012

Title: String Operations

AIM: Write a program to implement string operations like length, reverse, palindrome, case change etc.

OBJECTIVES: To understand String class and its associated methodsTo understand StringBuffer ClassTo understand significance of hashCode()

THEORY: In Java a string is a sequence of characters. But, unlike many other languages that implement strings as character arrays, Java implements strings as objects of type String.

Implementing strings as built-in objects allows Java to provide a full complement of features that make string handling convenient. For example, Java has methods to compare two strings, search for a substring, concatenate two strings, and change the case of letters within a string. Also, String objects can be constructed a number of ways, making it easy to obtain a string when needed.

Somewhat unexpectedly, when you create a String object, you are creating a string that cannot be changed. That is, once a String object has been created, you cannot change the characters that comprise that string. The difference is that each time you need an altered version of an existing string, a new String object is created that contains the modifications. The original string is left unchanged. This approach is used because fixed, immutable strings can be implemented more efficiently than changeable ones. For those cases in which a modifiable string is desired, there is a companion class to String called StringBuffer, whose objects contain strings that can be modified after they are created.

Both the String and StringBuffer classes are defined in java.lang. Thus, they are available to all programs automatically. Both are declared final, which means that neither of theseclasses may be subclassed. This allows certain optimizations that increase performance to take place on common string operations.

The String ConstructorsThe String class supports several constructors. To create an empty String, you call thedefault constructor. For example,String s = new String();will create an instance of String with no characters in it.

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Frequently, you will want to create strings that have initial values. The String class provides a variety of constructors to handle this. To create a String initialized by an array of characters, use the constructor shown here:String(char chars[ ])Here is an example:char chars[] = { 'a', 'b', 'c' };String s = new String(chars);This constructor initializes s with the string “abc”.

You can specify a subrange of a character array as an initializer using the following constructor: String(char chars[ ], int startIndex, int numChars) Here, startIndex specifies the index at which the subrange begins, and numChars specifies the number of characters to use. Here is an example:char chars[] = { 'a', 'b', 'c', 'd', 'e', 'f' };String s = new String(chars, 2, 3);This initializes s with the characters cde.You can construct a String object that contains the same character sequence as another String object using this constructor:String(String strObj)Here, strObj is a String object. Consider this example:// Construct one String from another.class MakeString {public static void main(String args[]) {char c[] = {'J', 'a', 'v', 'a'};String s1 = new String(c);String s2 = new String(s1);System.out.println(s1);System.out.println(s2);}}The output from this program is as follows:JavaJavaAs you can see, s1 and s2 contain the same string.

String LengthThe length of a string is the number of characters that it contains. To obtain this value, call the length( ) method, shown here:int length( )The following fragment prints “3”, since there are three characters in the string s:char chars[] = { 'a', 'b', 'c' };String s = new String(chars);System.out.println(s.length());

Special String OperationsBecause strings are a common and important part of programming, Java has added special support for several string operations within the syntax of the language. These operations

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include the automatic creation of new String instances from string literals, concatenation of multiple String objects by use of the + operator, and the conversion of other data types to a string representation. There are explicit methods available to perform all of these functions, but Java does them automatically as a convenience for the programmer and to add clarity.

The earlier examples showed how to explicitly create a String instance from an array of characters by using the new operator. However, there is an easier way to do this using astring literal. For each string literal in your program, Java automatically constructs a String object. Thus, you can use a string literal to initialize a String object. For example,the following code fragment creates two equivalent strings:

char chars[] = { 'a', 'b', 'c' };

String s1 = new String(chars);

String s2 = "abc"; // use string literal

Because a String object is created for every string literal, you can use a string literal any

place you can use a String object. For example, you can call methods directly on a quoted

string as if it were an object reference, as the following statement shows. It calls the length(

) method on the string “abc”. As expected, it prints “3”.

System.out.println("abc".length());

String ConcatenationIn general, Java does not allow operators to be applied to String objects. The one exception to this rule is the + operator, which concatenates two strings, producing a String object as the result. This allows you to chain together a series of + operations.For example, the following fragment concatenates three strings:String age = "9";String s = "He is " + age + " years old.";System.out.println(s);This displays the string “He is 9 years old.”

String Conversion & toString()When Java converts data into its string representation during concatenation, it does so by calling one of the overloaded versions of the string conversion method valueOf( ) defined by String. valueOf( ) is overloaded for all the simple types and for type Object. For the simple types, valueOf( ) returns a string that contains the human-readable equivalent of the value with which it is called. For objects, valueOf( ) calls the toString( ) method on the object. We will look more closely at valueOf( ) later in this chapter. Here, let’s examine the toString( ) method, because it is the means by which you can determine the string representation for objects of classes that you create.

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Every class implements toString( ) because it is defined by Object. However, the default

implementation of toString( ) is seldom sufficient. For most important classes that you

create, you will want to override toString( ) and provide your own string representations.

Fortunately, this is easy to do. The toString( ) method has this general form:

String toString( )

To implement toString( ), simply return a String object that contains the humanreadablestring that appropriately describes an object of your class. By overriding toString( ) for classes that you create, you allow them to be fully integrated into Java’s programming environment. For example, they can be used in print( ) and println( ) statements and in concatenation expressions.

Character ExtractionThe String class provides a number of ways in which characters can be extracted from a String object. Each is examined here. Although the characters that comprise a string within a String object cannot be indexed as if they were a character array, many of the String methods employ an index (or offset) into the string for their operation. Like arrays, the string indexes begin at zero.

charAt()To extract a single character from a String, you can refer directly to an individual character via the charAt( ) method. It has this general form:char charAt(int where)For example,char ch;ch = "abc".charAt(1);assigns the value “b” to ch.

getChars()If you need to extract more than one character at a time, you can use the getChars( )method. It has this general form:void getChars(int sourceStart, int sourceEnd, char target[ ], int targetStart)

String ComparisonThe String class includes several methods that compare strings or substrings within strings.

Equals & equalsIgnoreCase()To compare two strings for equality, use equals( ). It has this general form:boolean equals(Object str)Here, str is the String object being compared with the invoking String object. It returns true if the strings contain the same characters in the same order, and false otherwise. The comparison is case-sensitive.

To perform a comparison that ignores case differences, call equalsIgnoreCase( ). When it compares two strings, it considers A-Z to be the same as a-z. It has this general form:

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boolean equalsIgnoreCase(String str)

Here, str is the String object being compared with the invoking String object. It, too, returns true if the strings contain the same characters in the same order, and false otherwise.

startsWith() & endsWith()String defines two routines that are, more or less, specialized forms of regionMatches( ). The startsWith( ) method determines whether a given String begins with a specified string.Conversely, endsWith( ) determines whether the String inquestion ends with a specified string. They have the following general forms:boolean startsWith(String str)boolean endsWith(String str)Here, str is the String being tested. If the string matches, true is returned. Otherwise, false is returned. For example,"Foobar".endsWith("bar")and"Foobar".startsWith("Foo")are both true.

Searching StringsThe String class provides two methods that allow you to search a string for a specifiedcharacter or substring:■ indexOf( ) Searches for the first occurrence of a character or substring.■ lastIndexOf( ) Searches for the last occurrence of a character or substring.These two methods are overloaded in several different ways. In all cases, the methods return the index at which the character or substring was found, or –1 on failure.To search for the first occurrence of a character, use int indexOf(int ch)To search for the last occurrence of a character, useint lastIndexOf(int ch)Here, ch is the character being sought.To search for the first or last occurrence of a substring, useint indexOf(String str)int lastIndexOf(String str)Here, str specifies the substring.

Modifying a StringBecause String objects are immutable, whenever you want to modify a String, you must either copy it into a StringBuffer or use one of the following String methods, which will construct a new copy of the string with your modifications complete.

SubstringYou can extract a substring using substring( ). It has two forms. The first isString substring(int startIndex)

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Here, startIndex specifies the index at which the substring will begin. This form returns a copy of the substring that begins at startIndex and runs to the end of the invoking string.he second form of substring( ) allows you to specify both the beginning and ending index of the substring:String substring(int startIndex, int endIndex)

Here, startIndex specifies the beginning index, and endIndex specifies the stopping point. The string returned contains all the characters from the beginning index, up to, but not including, the ending index.

Concat()You can concatenate two strings using concat( ), shown here:String concat(String str)This method creates a new object that contains the invoking string with the contents of str appended to the end. concat( ) performs the same function as +. For example,String s1 = "one";String s2 = s1.concat("two");puts the string “onetwo” into s2. It generates the same result as the following sequence:String s1 = "one";String s2 = s1 + "two";

Replace()The replace( ) method replaces all occurrences of one character in the invoking string with another character. It has the following general form:

trim()The trim( ) method returns a copy of the invoking string from which any leading and trailing whitespace has been removed. It has this general form:String trim( )Here is an example:String s = " Hello World ".trim();This puts the string “Hello World” into s.

hashCode()A hash table can only store objects that override the hashCode( ) and equals( )methods that are defined by Object. The hashCode( ) method must compute andreturn the hash code for the object. Of course, equals( ) compares two objects. Fortunately, many of Java’s built-in classes already implement the hashCode( ) method. For example, the most common type of Hashtable uses a String object as the key. String implements both hashCode( ) and equals( ).

The Hashtable constructors are shown here:Hashtable( )Hashtable(int size)Hashtable(int size, float fillRatio)

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Hashtable(Map m)

FAQs:1. Why is the String class declared final?2. So the String class is final because its methods are complex?3. How many objects are created for identical strings?4. What’s the use of String constructor?5. How should I use the String constructor?6. What is the difference between String and StringBuffer?7. When should I use StringBuffer instead of String?8. What is a StringTokenizer for?9. How can I check a string has numbers?


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Title: Matrix Operations

AIM: Write a program to implement matrix operations like addition, subtraction, multiplication, transpose etc.

OBJECTIVES: To understand Arrays in javaTo understand how to declare and initialize multi dimensional array

THEORY:

Basics of ArrayAn array is a group of like-typed variables that are referred to by a common name. Arrays of any type can be created and may have one or more dimensions. A specific element in an array is accessed by its index. Arrays offer a convenient means of grouping related information.

One – Dimensional ArrayA one-dimensional array is, essentially, a list of like-typed variables. To create an array, you first must create an array variable of the desired type. The general form of a one dimensional array declaration is

type var-name[ ];

Here, type declares the base type of the array. The base type determines the data type of each element that comprises the array. Thus, the base type for the array determines what type of data the array will hold. For example, the following declares an array named month_days with the type “array of int”:

int month_days[];

Although this declaration establishes the fact that month_days is an array variable, no array actually exists. In fact, the value of month_days is set to null, which represents an array with no value. To link month_days with an actual, physical array of integers, you must allocate one using new and assign it to month_days. new is a special operator that allocates memory. You will look more closely at new in a later chapter, but you need to use it now to allocate memory for arrays. The general form of new as it applies to one-dimensional arrays appears as follows:

array-var = new type[size];

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Here, type specifies the type of data being allocated, size specifies the number of elements in the array, and array-var is the array variable that is linked to the array. That is, to use new to allocate an array, you must specify the type and number of elements to allocate. The elements in the array allocated by new will automatically be initialized to zero. This example allocates a 12-element array of integers and links them to month_days.

month_days = new int[12];

After this statement executes, month_days will refer to an array of 12 integers. Further, all elements in the array will be initialized to zero. Let’s review: Obtaining an array is a two-step process. First, you must declare a variable of the desired array type. Second, you must allocate the memory that will hold the array, using new, and assign it to the array variable. Thus, in Java all arrays are dynamically allocated. Once you have allocated an array, you can access a specific element in the array by specifying its index within square brackets. All array indexes start at zero. For example, this statement assigns the value 28 to the second element of month_days.

month_days[1] = 28;

The next line displays the value stored at index 3.

System.out.println(month_days[3]);

Arrays can be initialized when they are declared. The process is much the same as that used to initialize the simple types. An array initializer is a list of comma-separated expressions surrounded by curly braces. The commas separate the values of the array elements. The array will automatically be created large enough to hold the number of elements you specify in the array initializer.

Here is one more example that uses a one-dimensional array. It finds the average of a set of numbers.

// Average an array of values.class Average {

public static void main(String args[]) {double nums[] = {10.1, 11.2, 12.3, 13.4, 14.5};double result = 0;int i;for(i=0; i<5; i++)

result = result + nums[i];System.out.println("Average is " + result / 5);

}

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}Alternative Array DeclarationThere is a second form that may be used to declare an array:

type[ ] var-name;

Here, the square brackets follow the type specifier, and not the name of the array variable. For example, the following two declarations are equivalent:

int al[] = new int[3];int[] a2 = new int[3];

The following declarations are also equivalent:

char twod1[][] = new char[3][4];char[][] twod2 = new char[3][4];

This alternative declaration form is included as a convenience, and is also useful when specifying an array as a return type for a method.

Multidimensional ArraysIn Java, multidimensional arrays are actually arrays of arrays. These, as you might expect, look and act like regular multidimensional arrays. However, as you will see, there are a couple of subtle differences. To declare a multidimensional array variable, specify each additional index using another set of square brackets. For example, the following declares a two-dimensional array variable called twoD.

int twoD[][] = new int[4][5];

This allocates a 4 by 5 array and assigns it to twoD.The following program numbers each element in the array from left to right, top to bottom, and then displays these values:

// Demonstrate a two-dimensional array.class TwoDArray {

public static void main(String args[]) {int twoD[][]= new int[4][5];int i, j, k = 0;for(i=0; i<4; i++)

for(j=0; j<5; j++) {twoD[i][j] = k;k++;

}

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for(i=0; i<4; i++) {for(j=0; j<5; j++)

System.out.print(twoD[i][j] + " ");System.out.println();

}}

}

This program generates the following output:0 1 2 3 45 6 7 8 910 11 12 13 1415 16 17 18 19

When you allocate memory for a multidimensional array, you need only specify the memory for the first (leftmost) dimension. You can allocate the remaining dimensions separately. For example, this following code allocates memory for the first dimension of twoD when it is declared. It allocates the second dimension manually.

int twoD[][] = new int[4][];twoD[0] = new int[5];twoD[1] = new int[5];twoD[2] = new int[5];twoD[3] = new int[5];

Transpose of Matrix

In linear algebra, the transpose of a matrix A is another matrix AT (also written A′, Atr or At) created by any one of the following equivalent actions:

reflect A over its main diagonal (which runs top-left to bottom-right) to obtain AT

write the rows of A as the columns of AT

write the columns of A as the rows of AT

visually rotate A 90 degrees clockwise, and mirror the image in a vertical line to obtain AT

Formally, the (i,j) element of AT is the (j,i) element of A.

If A is an m × n matrix then AT is a n × m matrix. The transpose of a scalar is the same scalar.

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FAQs:1. How do we allocate an array dynamically in java?2. Explain with example how to initialize an array of objects.3. What is the difference between a Vector and Array? Discuss the advantages

and disadvantages of both.4. If I do not provide any arguments on the command line, then the String array

of Main method will be empty or null?


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Title: Inheritance and Interface

AIM: Write a program to implement the concepts of inheritance and interface for given problem statement:A class derived from Account that holds information about saving and current accountalso implements overrides method and print summary of saving and current account.

OBJECTIVES: To expose the concepts of inheritance and overriding

THEORY:

Basics of Inheritance

Inheritance is one of the cornerstones of object-oriented programming because it allowsthe creation of hierarchical classifications. Using inheritance, you can create a generalclass that defines traits common to a set of related items. This class can then be inherited by other, more specific classes, each adding those things that are unique to it. In theterminology of Java, a class that is inherited is called a super class. The class that doesthe inheriting is called a subclass. Therefore, a subclass is a specialized version of a superclass. It inherits all of the instance variables and methods defined by the super class.

To inherit a class, you simply incorporate the definition of one class into another by using the ‘extends’ keyword. To see how, let’s begin with a short example. The following program creates a super class called A and a subclass called B. Notice how the keyword extends is used to create a subclass of A.

The general form of a class declaration that inherits a superclass is shown here:class subclass-name extends superclass-name {// body of class}

General Example of Simple Inheritance Is As Given Below// Crate a base classclass A {// body of base class}

// Create a subclass by extending class A class B extends A {

// body of derived class}

class SimpleInheritance {public static void main(String args[]) {

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// … } }You can only specify one super class for any subclass that you create. Java does notsupport the inheritance of multiple super classes into a single subclass. (This differs fromC++, in which you can inherit multiple base classes.) You can, as stated, create a hierarchy of inheritance in which a subclass becomes a super class of another subclass.However, no class can be a super class of itself.

Using superWhenever a subclass needs to refer to its immediate super class, it can do so by useof the keyword super .super has two general forms. The first calls the super class’constructor. The second is used to access a member of the super class that has beenhidden by a member of a subclass. Each use is examined here.Using super to Call Super class Constructors

A subclass can call a constructor method defined by its super class by use of the followingform of super:

super(parameter-list);

A parameter-list specifies any parameters needed by the constructor in the super classsuper( ) must always be the first statement executed inside a subclass’ constructor.

To see how super( ) is used, consider this example

// BoxWeight now uses super to initialize its Box attributes. class BoxWeight extends Box {double weight; // weight of box

// initialize width, height, and depth usingsuper() BoxWeight(double w, double h, doubled, double m) { super(w, h, d); // call superclassconstructorweight = m;}}Here, BoxWeight( ) calls super( ) with the parameters w, h, and d. This causes the Box() constructor to be called, which initializes width, height, and depth using these values. BoxWeight no longer initializes these values itself. It only needs to initialize thevalue unique to it: weight. This leaves Box free to make these values private ifdesired. In the preceding example, super( ) was called with three arguments. Sinceconstructors can be overloaded, super() can be called using any form defined by thesuperclass. The constructor executed will be the one that matches the arguments. Forexample, here is a complete implementation of BoxWeight that provides constructorsfor the various ways that a box can be constructed. In each case, super( ) is calledusing the appropriate arguments. Notice that width, height, and depth have been madeprivate within Box.

Overriding and Hiding Members

Under certain circumstances, a subclass may override non-static methods defined in the super class that would otherwise be inherited. When the method is invoked on an

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object of the subclass, it is the new method implementation in the subclass that is executed.The overridden method in the super class is not inherited by the subclass, and the newmethod in the subclass must uphold the following rules of method overriding:The new method definition must have the same method signature (i.e., method name and parameters) and the same return type.

Whether parameters in the overriding method should be final is at the discretion of the subclass. A method's signature does not encompass the final modifier of parameters, only their types and order.The new method definition cannot narrow the accessibility of the method, but it can widen it. The new method definition can only specify all or none, or a subset of the exception classes (including their subclasses) specified in the throws clause of theoverridden method in the super class.An instance method in a subclass cannot override a static method in the super class. Thecompiler will flag this as an error. A static method is class-specific and not part of any object, while overriding methods are invoked on behalf of objects of the subclass.However, a static method in a subclass can hide a static method in the super class.A final method cannot be overridden because the modifier final prevents methodoverriding. An attempt to override a final method will result in a compile-time error.However, an abstract method requires the non-abstract subclasses to override themethod, in order to provide an implementation.Accessibility modifier private for a method means that the method is not accessible outsidethe class in which it is defined; therefore, a subclass cannot override it. However, asubclass can give its own definition of such a method, which may have the same signatureas the method in its super class.

Overriding vs. Overloading

Method overriding should not be confused with method overloading. Method overridingrequires the same method signature (name and parameters) and the same return type. Onlynon-final instance methods in the superclass that are directly accessible from the subclassare eligible for overriding. Overloading occurs when the method names are the same,but the parameter lists differ. Therefore, to overload methods, the parameters must differin type, order, or number. As the return type is not a part of the signature, havingdifferent return types is not enough to overload methods.

InterfacesUsing the keyword interface, you can fully abstract a class’ interface from its implementation. That is, using interface, you can specify what a class must do, but not how it does it. Interfaces are syntactically similar to classes, but they lack instance variables, and their methods are declared without any body. In practice, this means that you can define interfaces which don’t make assumptions about how they are implemented. Once it is defined, any number of classes can implement an interface. Also, one class can implement any number of interfaces.

To implement an interface, a class must create the complete set of methods defined by the interface. However, each class is free to determine the details of its own implementation. By providing the interface keyword, Java allows you to fully utilize the “one interface, multiple methods” aspect of polymorphism. Interfaces are designed to support dynamic method resolution at run time.

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Normally, in order for a method to be called from one class to another, both classes need to be present at compile time so the Java compiler can check to ensure that the method signatures are compatible. This requirement by itself makes for a static and non extensible classing environment. Inevitably in a system like this, functionality gets pushed up higher and higher in the class hierarchy so that the mechanisms will be available to more and more subclasses. Interfaces are designed to avoid this problem. They disconnect the definition of a method or set of methods from the inheritance hierarchy. Since interfaces are in a different hierarchy from classes, it is possible for classes that are unrelated in terms of the class hierarchy to implement the same interface. This is where the real power of interfaces is realized.

Defining InterfaceAn interface is defined much like a class. This is the general form of an interface:access interface name {return-type method-name1(parameter-list);return-type method-name2(parameter-list);type final-varname1 = value;type final-varname2 = value;// ...return-type method-nameN(parameter-list);type final-varnameN = value;}

Here, access is either public or not used. When no access specifier is included, then default access results, and the interface is only available to other members of the package in which it is declared. When it is declared as public, the interface can be used by any other code. name is the name of the interface, and can be any valid identifier.

Notice that the methods which are declared have no bodies. They end with a semicolon after the parameter list. They are, essentially, abstract methods; there can be no defaultimplementation of any method specified within an interface. Each class that includes an interface must implement all of the methods.

Variables can be declared inside of interface declarations. They are implicitly final and static, meaning they cannot be changed by the implementing class. They must also be initialized with a constant value. All methods and variables are implicitly public if the interface, itself, is declared as public.

Implementing an InterfaceOnce an interface has been defined, one or more classes can implement that interface. To implement an interface, include the implements clause in a class definition, and then create the methods defined by the interface. The general form of a class that includes the implements clause looks like this:

access class classname [extends superclass][implements interface [,interface...]] {// class-body}

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Here, access is either public or not used. If a class implements more than one interface, the interfaces are separated with a comma. If a class implements two interfaces that declare the same method, then the same method will be used by clients of either interface. The methods that implement an interface must be declared public. Also, the type signature of the implementing method must match exactly the type signature specified in the interface definition.

FAQs:1. Can an inner class declared inside of method access local variables of this method?2. What's the main difference between a Vector and an ArrayList?3. You can create an abstract class that contains only abstract methods. On the other

hand, you can create an interface that declares the same methods. So can youuse abstract classes instead of interfaces?

4. What access level do you need to specify in the class declaration to ensure that only classes from the same directory can access it?

5. When you declare a method as abstract method?6. Can I call a abstract method from a non abstract method?7. What is the difference between an Abstract class and Interface in Java? or can you

explain when you use Abstract classes ?8. What is the purpose of garbage collection in Java, and when is it used?9. What is the purpose of finalization?10. What is the difference between static and non-static variables?11. How are this() and super() used with constructors?12. What are some alternatives to inheritance?

CONCLUSION:Students should write their own conclusion here.

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Title: JDBC Connectivity

AIM: Write a program to connect to database using JDBC connectivity

OBJECTIVES: To expose the concept of JDBC connectivityTo understand how JDBC connectivity helps to get connected with many database systems though java program

THEORY: Basics of JDBCThe JDBC (Java Database Connectivity) API defines interfaces and classes for writing database applications in Java by making database connections. Using JDBC you can send SQL, PL/SQL statements to almost any relational database. JDBC is a Java API for executing SQL statements and supports basic SQL functionality. It provides RDBMS access by allowing you to embed SQL inside Java code. Because Java can run on a thin client, applets embedded in Web pages can contain downloadable JDBC code to enable remote database access. You will learn how to create a table, insert values into it, query the table, retrieve results, and update the table with the help of a JDBC Program example.Although JDBC was designed specifically to provide a Java interface to relational databases, you may find that you need to write Java code to access non-relational databases as well.

JDBC Connectivity Steps

Before you can create a java jdbc connection to the database, you must first import thejava.sql package.

import java.sql.*; The star ( * ) indicates that all of the classes in the package java.sql are to be imported.

1. Loading a database driver

In this step of the jdbc connection process, we load the driver class by calling Class.forName() with the Driver class name as an argument. Once loaded, the Driver class creates an instance of itself. A client can connect to Database Server through JDBC Driver. Since most of the Database servers support ODBC driver therefore JDBC-ODBC Bridge driver is commonly used.The return type of the Class.forName (String ClassName) method is “Class”. Class is a class injava.lang package.

try {Class.forName(”sun.jdbc.odbc.JdbcOdbcDriver”); //Or any other driver

}catch(Exception x){System.out.println( “Unable to load the driver class!” );}

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2.Creating a oracle jdbc Connection

The JDBC DriverManager class defines objects which can connect Java applications to a JDBC driver. DriverManager is considered the backbone of JDBC architecture. DriverManager class manages the JDBC drivers that are installed on the system. Its getConnection() method is used to establish a connection to a database. It uses a username, password, and a jdbc url to establish a connection to the database and returns a connection object. A jdbc Connection represents a session/connection with a specific database. Within the context of a Connection, SQL, PL/SQL statements are executed and results are returned. An application can have one or more connections with a single database, or it can have many connections with different databases. A Connection object provides metadata i.e. information about the database, tables, and fields. It also contains methods to deal with transactions.

JDBC URL Syntax:: jdbc: <subprotocol>: <subname>

JDBC URL Example:: jdbc: <subprotocol>: <subname>•Each driver has its own subprotocol•Each subprotocol has its own syntax for the source. We’re using the jdbc odbc subprotocol, so the DriverManager knows to use the sun.jdbc.odbc.JdbcOdbcDriver.

try{Connection dbConnection=DriverManager.getConnection(url,”loginName”,”Password”)}catch( SQLException x ){

System.out.println( “Couldn’t get connection!” );

}

3. Creating a jdbc Statement object

Once a connection is obtained we can interact with the database. Connection interface defines methods for interacting with the database via the established connection. To execute SQL statements, you need to instantiate a Statement object from your connection object by using the createStatement() method.

Statement statement = dbConnection.createStatement();

A statement object is used to send and execute SQL statements to a database.

Three kinds of Statements

Statement: Execute simple sql queries without parameters.Statement createStatement()Creates an SQL Statement object.

Prepared Statement: Execute precompiled sql queries with or without parameters.PreparedStatement prepareStatement(String sql)returns a new PreparedStatement object. PreparedStatement objects are precompiledSQL statements.

Callable Statement: Execute a call to a database stored procedure.CallableStatement prepareCall(String sql)

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returns a new CallableStatement object. CallableStatement objects are SQL stored procedure call statements.

4. Executing a SQL statement with the Statement object, and returning a jdbc resultSet.

Statement interface defines methods that are used to interact with database via the execution of SQL statements. The Statement class has three methods for executing statements:executeQuery(), executeUpdate(), and execute(). For a SELECT statement, the method to use is executeQuery . For statements that create or modify tables, the method to use is executeUpdate. Note: Statements that create a table, alter a table, or drop a table are all examples of DDLstatements and are executed with the method executeUpdate. execute() executes an SQLstatement that is written as String object.

ResultSet provides access to a table of data generated by executing a Statement. The table rows are retrieved in sequence. A ResultSet maintains a cursor pointing to its current row of data. The next() method is used to successively step through the rows of the tabular results.

ResultSetMetaData Interface holds information on the types and properties of the columns in a ResultSet. It is constructed from the Connection object.

Java JDBC Connection Example, JDBC Driver Example

import java.sql.*;

public class JDBCSample {

/**

* @param args

*/

public static void main(String[] args) {

// TODO Auto-generated method stub

ResultSet rs;

try

{

Class.forName("oracle.jdbc.driver.OracleDriver");

Connection conn =DriverManager.getConnection("jdbc:oracle:thin:@127.0.0.1:1521:xe","system","Oracle10g");

Statement st = conn.createStatement();

rs = st.executeQuery("select * from studinfo");

while(rs.next())

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System.out.println(rs.getString(1)+ "|" + rs.getInt(2)+ "|" + rs.getString(3));

st.close();

conn.close();

}

catch(Exception e)

{ System.out.println(e);

}

}

}

Output:

javac JDBCSample.java

Java JDBCSample

ajay|100|te itrahul|101|te itpayal|102|te itmanavi|103|te it

JDBC DriversType I: “Bridge”Type II: “Native”Type III: “Middleware”Type IV: “Pure”

JDBC Object Classes DriverManager

Loads, chooses drivers Driver

Connects to actual database Connection

A series of SQL statement to and from the DB Statement

A single SQL statement ResultSet

The records returned from a statement

FAQs:1. What are the steps involved in establishing a JDBC connection?2. How can you load the drivers?3. What will Class.forName do while loading drivers?4. How can you make the connection?

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5. How can you create JDBC statements and what are they?6. How can you retrieve data from the ResultSet?7. What are the different types of Statements?8. How can you use PreparedStatement?9. What does setAutoCommit do?


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Section II:- Client Side TechnologiesAssignment No.: 6 Date: 06-02-2012

Title: HTML – Scripting Language

AIM: Study of Hyper Text Markup Language and its’ tags. Create a HTML page to display all information about bank account.

OBJECTIVES: To expose the concepts of HTML, different tags.

THEORY:

What is Client-Side Programming

Browser is “Universal Client”Want power and appearance of applicationIncrease functionalityProvide more capable Graphic User Interface(GUI) Incorporate new types of informationMove functionality from server to client

Advantages

Reduce load on server, network traffic, network delayUse client processing power and resources, scale with number of clientsLocalize processing where it is neededCan be simpler than using server side processing

Disadvantages

Possible need for client disk space and other resourcesIncreased complexity of client environment Increased complexity of web pages Distribution and installation issuesReduced portabilitySecurity

Security Issues

Unauthorized access to machine resources: disk, cpu etc.o (e.g. format disk) Unauthorized access to informationo (e.g. upload history, files) Denial of serviceo (e.g. crash machine)

TechniquesFeatures of HTML 3.2 and extensions Browser-supported scripting languages JavaAppletsCombined approachesDynamic HTML

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Client-side programming involves writing code that is interpreted by a browser suchas Internet Explorer or Mozilla Firefox or by any other Web client such as a cell phone.The most common languages and technologies used in client-side programming are HTML, JavaScript, Cascading Style Sheets (CSS) and Macromedia Flash.

Introduction to HTMLHTML (Hypertext Markup Language) is used to create document on the World WideWeb. It is simply a collection of certain key words called ‘Tags’ that are helpful in writingthe document to be displayed using a browser on Internet. It is a platform independentlanguage that can be used on any platform such as Windows, Linux, Macintosh, and so on.To display a document in web it is essential to mark-up the different elements (headings,paragraphs, tables, and so on) of the document with the HTML tags. To view a mark-up document, user has to open the document in a browser. A browser understands and interprets the HTML tags, identifies the structure of the document (which part are which) and makes decision about presentation (how the parts look) of the document.HTML also provides tags to make the document look attractive usinggraphics, font size and colors. User can make a link to the other document or the differentsection of the same document by creating Hypertext Links also known as Hyperlinks.HyperText Markup Language (HTML) is the language behind most Web pages. The language is made up of elements that describe the structure and format of the content on aWeb page. Cascading Style Sheets (CSS) is used in HTML pages to separateformatting and layout from content. Rules defining color, size, positioning and otherdisplay aspects of elements are defined in the HTML page or in linked CSS pages.

HTML SkeletonAn HTML page contains what can be thought of as a skeleton - the main structure of thepage. It looks like this:<html><head><title></title>

</head><body>

</body></html>

Elements in HTML DocumentsThe HTML instructions, along with the text to which the instructions apply, are calledHTML elements. The HTML instructions are themselves called tags, and look like<element_name> - that is, they are simply the element name surrounded by left and rightangle brackets.Most elements mark blocks of the document for particular purpose or formatting:the above <element_name> tag marks the beginning of such as section. The end ofthis section is then marked by the ending tag </element_name> -- note the leadingslash character "/" that appears in front of the element name in an end tag. End, or stoptags are always indicated by this leading slash character.For example, the heading at the top of this page is an H2 element, (a level 2 heading)which is written as:

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<H2> 2.1 Elements in HTML </H2>.

The <head> ElementThe <head> element contains content that is not displayed on the page itself. Some of the elements commonly found in the <head> are:Title of the page (<title>). Browsers typically show the title in the "title bar" at the top of the browser window. Meta tags, which contain descriptive information about the page<meta />) Script blocks, which contain javascript or vbscript code for addingfunctionality and interactivity to a page (<script>) Style blocks, which contain CascadingStyle Sheet rules (<style>). References (or links) to external style sheets (<link />).

The <body> ElementThe <body> element contains all of the content that appears on the page itself. Body tagswill be covered thoroughly throughout this manual

EmptyElementsSome elements are empty -- that is, they do not affect a block of the document insome way. These elements do not require an ending tag. An example is the <HR>element, which draws a horizontal line across the page. This element would simply beentered as<HR>

Upper and LowerCaseElement names are case insensitive. Thus, the the horizontal rule element can be writtenas any of <hr>, <Hr>or <HR>.

Elements can have AttributesMany elements can have arguments that pass parameters to the interpreter handling thiselement. These arguments are called attributes of the element. For example, considerthe element A, which marks a region of text as the beginning (or end) of a hypertext link.This element can have several attributes. One of them, HREF, specifies the hypertextdocument to which the marked piece of text is linked. To specify this in the tag for A youwrite:<A HREF="http://www.somewhere.ca/file.html"> marked text </a>.

where the attribute HREF is assigned the indicated value. Note that the A element is notempty, and that it is closed by the tag </a>. Note also that end tags never take attributes -- the attributes to an element are always placed in the start tag.

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Various Tags of HTML

Tag Description

 Defines a comment

<!DOCTYPE> Defines the document type

<a> Defines an anchor

<abbr> Defines an abbreviation

<acronym> Defines an acronym

<address> Defines contact information for the author/owner of a document

<applet> Deprecated. Defines an embedded applet

<area/> Defines an area inside an image-map

<b> Defines bold text

<base/> Defines a default address or a default target for all links on a page

<basefont/> Deprecated. Defines a default font, color, or size for the text in a page

<bdo> Defines the text direction

<big> Defines big text

<blockquote> Defines a long quotation

<body> Defines the document's body

<br/> Defines a single line break

<button> Defines a push button

<caption> Defines a table caption

<center> Deprecated. Defines centered text

<cite> Defines a citation

<code> Defines computer code text

<col/> Defines attribute values for one or more columns in a table

<colgroup> Defines a group of columns in a table for formatting

<dd> Defines a description of a term in a definition list

<del> Defines deleted text

<dfn> Defines a definition term

<dir> Deprecated. Defines a directory list

<div> Defines a section in a document

<dl> Defines a definition list

<dt> Defines a term (an item) in a definition list

<em> Defines emphasized text

<fieldset> Defines a border around elements in a form

<font> Deprecated. Defines font, color, and size for text

<form> Defines an HTML form for user input

<frame/> Defines a window (a frame) in a frameset

<frameset> Defines a set of frames

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<h1>to<h6> Defines HTML headings

<head> Defines information about the document

<hr/> Defines a horizontal line

<html> Defines an HTML document

<i> Defines italic text

<iframe> Defines an inline frame

<img/> Defines an image

<input/> Defines an input control

<ins> Defines inserted text

<isindex> Deprecated. Defines a searchable index related to a document

<kbd> Defines keyboard text

<label> Defines a label for an input element

<legend> Defines a caption for a fieldset element

<li> Defines a list item

<link/> Defines the relationship between a document and an external resource

<map> Defines an image-map

<menu> Deprecated. Defines a menu list

<meta/> Defines metadata about an HTML document

<noframes> Defines an alternate content for users that do not support frames

<noscript> Defines an alternate content for users that do not support client-side scripts

<object> Defines an embedded object

<ol> Defines an ordered list

<optgroup> Defines a group of related options in a select list

<option> Defines an option in a select list

<p> Defines a paragraph

<param/> Defines a parameter for an object

<pre> Defines preformatted text

<q> Defines a short quotation

<s> Deprecated. Defines strikethrough text

<samp> Defines sample computer code

<script> Defines a client-side script

<select> Defines a select list (drop-down list)

<small> Defines small text

<span> Defines a section in a document

<strike> Deprecated. Defines strikethrough text

<strong> Defines strong text

<style> Defines style information for a document

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<sub> Defines subscripted text

<sup> Defines superscripted text

<table> Defines a table

<tbody> Groups the body content in a table

<td> Defines a cell in a table

<textarea> Defines a multi-line text input control

<tfoot> Groups the footer content in a table

<th> Defines a header cell in a table

<thead> Groups the header content in a table

<title> Defines the title of a document

<tr> Defines a row in a table

<tt> Defines teletype text

<u> Deprecated. Defines underlined text

<ul> Defines an unordered list

<var> Defines a variable part of a text

<xmp> Deprecated. Defines preformatted text

FAQs:1. What is Client side programming?2. What is the difference between client side and server side programming?3. What is mark up language?4. What is HTML?5. What are the different html tags?6. What is static and dynamic HTML?


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Title: Java Applets

AIM: Implement a Java Applet application to display all information about bank account.

OBJECTIVES: To expose the concepts of Java Applet

THEORY: Basics of Java AppletJava is a programming language. Developed in the years 1991 to 1994 by SunMicrosystems. Programs written in Java are called applets. First browser that could show applets was introduced in 1994, as "WebRunner" - later known as "The HotJava Browser".

An Applet is a program written in the Java programming language that can beincluded in an HTML page.

When you use a Java technology-enabled browser to view a page that contains an applet, theapplet's code is transferred to your system and executed by the browser's Java Virtual Machine (JVM).

Applet– Program that runs in• appletviewer (test utility for applets)• Web browser (IE, Communicator)– Executes when HTML (Hypertext Markup Language) document containing appletis opened and downloaded– Applications run in command windows

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FAQs:1. What is an applet? How does applet differ from applications?2. Explain with an example how we implement an applet into a web page using applet

tag. 3. What are the attributes of Applet tags? Explain the purposes.4. How can we determine the width and height of my applet?5. Explain how to set the background color within the applet area.6. What are methods that controls an applet’s life cycle, i.e. init, start, stop and destroy?


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Title: Mini Project Based on Section I & II

AIM: To develop your own system using Java Swing

OBJECTIVES: To expose the concepts of Java Swing and GUI design

THEORY: Introduction to Java Swing"Swing" refers to the new library of GUI controls (buttons, sliders, checkboxes, etc.) that replaces the somewhat weak and inflexible AWT controls

Main New Features Lightweight. Not built on native window-system windows. Much bigger set of built-in controls. Trees, image buttons, tabbed panes, sliders,

toolbars, color choosers, tables, text areas to display HTML or RTF, etc. Much more customizable. Can change border, text alignment, or add image to

almost any control. Can customize how minor features are drawn. Can separate internal

representation from visual appearance. Pluggable" look and feel. Can change look and feel at runtime, or design own look

and feel. Many miscellaneous new features. Double-buffering built in, tool tips, dockable tool

bars, keyboard accelerators, custom cursors, etc.

About JFC:-Java Foundation Classes

o Enterprise-level Java functionalityo Designed to create sophisticated front-end appso Contained in Java 2

JFC includes these APIs: AWT 2D API Drag & drop Assistive technology Swing

About SwingA GUI component framework

A set of Java classes and interfaces for creating graphical interfaces A follow-on to AWT

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The Swing API provides: A rich set of predefined components A basis for creating sophisticated custom components

Importance of SwingLightweight" components

Pure Java (no native counterpart) Require less overhead

A much richer set of components, including: Database-bound tables Trees Toolbars Progress bars Buttons, menus and lists that use graphics More flexible than AWT

Lets you Create non-rectangular components Combine components Customize look & feel (L&F)

Sophisticated built-in features: Tooltips Borders and insets Double-buffering for cleaner displays Slow-motion graphics for debugging

Additional Swing APIs for: Sophisticated text editing (e.g. HTML, RTF) Undo/redo

Project Description The project developed should cover all features of swing and should be efficiently

utilized for further process. Student should be able to develop a project by using the concept of inheritance and

be able to work with concept of oops with AWT and SWING. Students should attach their project snaps along with the database schema

description

Swing vs. AWTSwing is built on AWT

AWT provides interface to native components JComponent extends java.awt.Container

Swing has replacements for most AWT components E.g. JButton, JLabel replace Button, Label

What Swing uses from AWT: Base classes

Component, ContainerTop-level containers

Applet, Window, Frame, Dialog

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FAQs:1. What is the difference between Swing and AWT components?2. Name the containers which use Border Layout as their default layout?3. How can a GUI component handle its own events?4. What is the difference between the paint() and repaint() methods?5. Which package has light weight components?6. What are peerless components?7. What is a Container in a GUI?8. Why does JComponent have add() and remove() methods but Component does not?9. How would you create a button with rounded edges?

CONCLUSION & FUTURE SCOPE:Student should write in brief functionality achieved and future scope of their project.

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Section III:- Server Side TechnologiesAssignment No.: 9 Date: 27-02-2012

Title: Servlets, JSP

AIM: Study of Servlets, JSP, JDBC API and tomcat server.

OBJECTIVES: To expose the concepts & features of Java Servlets, JSP, Tomcat server.

THEORY: Server Side ProgrammingServer-side scripting is a web server technology in which a user's request is fulfilled by running a script directly on the web server to generate dynamic web pages. It is usually used to provide interactive web sites that interface to databases or other data stores. This is different from client-side scripting where scripts are run by the viewing web browser, usually in JavaScript. The primary advantage to server-side scripting is the ability to highly customize the response based on the user's requirements, access rights, or queries into data stores.

Server Side Programs for JAVA platformsJava ServletsJava Server Pages (JSPs)Enterprise Java Beans (EJBs)

Basics of ServletsA servlet is a Java programming language class used to extend the capabilities of servers that host applications accessed via a request-response programming model. Although servlets can respond to any type of request, they are commonly used to extend the applications hosted by Web servers. For such applications, Java Servlet technology defines HTTP-specific servlet classes.The javax.servlet , javax.servlet.http packages provide interfaces and classes for writing servlets. All servlets must implement the Servlet interface.When implementing a generic service, you can use or extend the GenericServlet class provided with the Java Servlet API. The HttpServlet class provides methods, such as doGet and doPost, for handling HTTP-specific services.

Life cycle of servletsThe life cycle of a servlet is controlled by the container in which the servlet has been deployed.When a request is mapped to a servlet, the container performs the following steps.If an instance of the servlet does not exist, the Web containerLoads the servlet class.Creates an instance of the servlet class.Initializes the servlet instance by calling the init method. Initialization is covered in Initializing a Servlet.Invokes the service method, passing a request and response object. .

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If the container needs to remove the servlet, it finalizes the servlet by calling the servlet's destroy method.Setting up a Servlet development environmentList of required softwares

1. JAVA 1.5 or 1.62. Tomcat 5.5.163. eclipse 3.3

First of all you need the Java software development kit 1.5 or 1.6 (JAVA SDK) installed.

Checking if JAVA is already installed in your systemFollow this step to check if Java software development kit (JDK) is already installed yoursystem. To determine if JAVA SDK is already installed in your system, run the followingcommand from command prompt.

> Java –versionIf JAVA platform is already installed, it will display the version of the JAVA SDK. Belowscreen shows JAVA version 1.6 running on a windows system. If command executessuccessfully and shows JAVA version 1.6, you can skip the next step.otherwise download and install the Java SDK as explained in next step.

Install JAVA SDKFirst thing you need to install is Java software development kit (Java SDK) . Download the Java development kit 6 (JDK 6) from Sun Java SE Download site. Current latest version is JDK 6 update 6.

Set up the JAVA_HOME environment variableOnce the JAVA SDK is installed follow this step to set the JAVA_HOME environment variable.

If JAVA_HOME variable is already set, you can skip this step.Right click on My Computer icon on your desktop it will open a popup menu, click onproperties, it will open the system properties window, then click on advanced tab. Click on environment variables button, it will open the environment variables window as shown in figure below. Initially there will be no JAVA_HOME environment variable set as shown infigure.Click on new button to add new system variable JAVA_HOME.

In the variable name filed, enter JAVA_HOME. Specify the path to root directory of JAVAinstallation in variable value field and click OK button. Now JAVA_HOME will appear under user variables.Next you need to add bin directory under the root directory of JAVA installation in PATH environment variable.Select the PATH variable from System variables and click on Edit button.

Add: ;%JAVA_HOME%\bin; at the end of variable value field and click OK button.Now verify that everything is correct by following the step: Checking if JAVA is alreadyinstalled in your system. It should show the version of the installed JAVA SDK.

Installing TomcatTomcat is an opensource web container. it is also web container reference implementation. You will need tomcat 5.5.16 installed on your system to test various servlet and JSP

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examples given in other tutorials. Download the jakarta-tomcat-5.0.28.tar.gz and extract it to the directory of your choice.

Note: This directory is referred as TOMCAT_HOME in other tutorialsThat’s all, tomcat is installed. It’s very easy, isn’t it?

Starting and shutting down TomcatTo start the tomcat server, open the command prompt, change the directory to TOMCATHOME/bin and run the startup.bat file. It will start the server.> startupTo shut down the tomcat server, run the shutdown.bat file. It will stop the server.> shutdown

Verifying Tomcat installationTo verify that tomcat is installed properly, start the server as explained above, open the webbrowser and access the following URL.http://localhost:8080/index.jspIt should show the tomcat welcome page, if tomcat is installed properly and server is running.

Setting up the CLASSPATHNow you need to create a new environment variable CLASSPATH if it is not already set. Weneed to add the servlet-api.jar into the CLASSPATH to compile the Servlets. Follow the samesteps as you did to create the JAVA_HOME variable. Create a new variable CLASSPATH under system variables. Add TOMCAT_HOME/lib/servlet-api.jar in variable value field.

Note: here TOMCAT_HOME refers to the tomcat installation directory.Introduction to Java ServletsNow you have the basic understanding of the HTTP protocol, web containers, and J2EE webapplication structure. Before you start learning Servlet API, this tutorial provides the basicunderstanding of the Java Servlets.

Basics of JSPJavaServer Pages (JSP) technology provides a simplified, fast way to create dynamic webcontent. JSP technology enables rapid development of web-based applications that are serverandplatform-independent.

JavaServer Pages (JSP) is a Java technology that helps software developers serve dynamicallygenerated web pages based on HTML, XML, or other document typesJSP pages typically comprise of:Static HTML/XML components.Special JSP tagsOptionally, snippets of code written in the Java programming language called "scriptlets."

JSP AdvantagesWrite Once Run Anywhere: JSP technology brings the "Write Once, Run Anywhere" paradigmto interactive Web pages. JSP pages can be moved easily across platforms, and across webservers, without any changes.

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Dynamic content can be served in a variety of formats: There is nothing that mandates the statictemplate data within a JSP page to be of a certain format. Consequently, JSP can service adiverse clientele ranging from conventional browsers using HTML/DHTML, to handheldwireless devices like mobile phones and PDAs using WML, to other B2B applications usingXML.

Recommended Web access layer for n-tier architecture: Sun's J2EE Blueprints, which offersguidelines for developing large-scale applications using the enterprise Java APIs, categoricallyrecommends JSP over servlets for serving dynamic content.

Completely leverages the Servlet API: If you are a servlet developer, there is very little that youhave to "unlearn" to move over to JSP. In fact, servlet developers are at a distinct advantagebecause JSP is nothing but a high-level abstraction of servlets. You can do almost anything thatcan be done with servlets using JSP--but more easily!

JSP using scripting elements, page directive and standard tags.List of the tags used in Java Server Pages:

Declaration tag Expression tag Directive tag Scriptlet tag Action tag

FAQs:1. What are the ways to write comments in the JSP page? Give example.2. Write Sample Code to pass control from one JSP page to another?3. How will you handle the exception without sending to error page? How will you set a4. message detail to the exception object?5. What is JSP Fragment?6. What is the difference between jsp and servlet life cycles?7. Why we need web container to Deploy the servlet or jsp ?8. Why main() is not written in servlets programs?9. What is the difference between http session and application session?10. Where do you declare methods in JSP?11. How to disable browser "Back" and "Forward" button from a JSP page?12. Can we use main method inside JSP? Why?


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Title: Main Project Based on Section I, II & III

AIM: To develop your own system by making use of Section I, II & III concepts and features

OBJECTIVES: To develop a web based system.

THEORY: Project Description

The project developed should cover maximum features of core Java, Swing, AWT, JSP, Servlets, JDBC Connectivity etc.

Students should attach their project snaps along with the database schema description.

Java doc of complete system should be created. Final project report should be presented.

CONCLUSION & FUTURE SCOPE:Student should write in brief functionality achieved and future scope of their project.

Education

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