Porting Pleso framework Demo to Netbeans and MySQL

Author: E. OzkanCompany: OzTech IT Consultants

Email: eozkan@oztech.euDate: 30-Jan-2009

1. ScopeWe are planning to use GWT to develop GUIs for a database application. Logically, we have focussed on CRUD applications. We identified a few candidates for our purpose and Pleso framework was one of them. Since we are using Netbeans and MySQL, we decided to port the demo application to our environment. This document summarizes our experience.

2. Environment• NetBeans IDE 6.5,• Java 1.6.0 Update 11,• MySQL Server 5.1,

• GWT 1.5.3• Pleso Framework 0.2 beta• Ibatis 2.3.3.720

It is also assumed that the gwt4nb plugin has been installed into the Netbeans IDE.

3. Migration StepsSelect File->New Project … from the Netbeans main menu.

Provide a project name “gwt_pleso_mysql_demo” and click on the Next button.

Use defaults for server and settings and click on the Next button:

Select “Google Web Toolkit” frameworks option and click on the Finish button:

Create a new Java Package under Source Packages:

Provide name of the java package: net.pleso.auth:

Copy source files from the original demo package (drag-drop from windows explorer). There is a one-to-one mapping between folders containing source code and netbeans packages. For example, contents of the src\net\pleso\auth folder should be copied into the net.pleso.auth package. Repeat same procedure for the remaining packages net.pleso.demo (without folders), net.pleso.demo.server and net.pleso.demo.client.

The files demo.html and style.css in the folder src\net\pleso\demo\public must be copied into the Web Pages:

Edit the web.xml file in the Configuration Files and copy servlet definitions and mappings from the file web.xml in the folder src\net\pleso\demo:

<servlet><servlet-name>AuthService</servlet-name><servlet -class>net.pleso.demo.server.auth.AuthServiceImpl</servlet-class>

</servlet>

<servlet-mapping><servlet-name>AuthService</servlet-name><url-pattern>/auth</url-pattern>

</servlet-mapping>

<servlet><servlet-name>BankService</servlet-name><servlet-class>net.pleso.demo.server.bank.BankServiceImpl</servlet-class>

</servlet><servlet-mapping>

<servlet-name>BankService</servlet-name><url-pattern>/bank</url-pattern>

</servlet-mapping>

<servlet><servlet-name>OperationService</servlet-name><servlet-class>net.pleso.demo.server.operation.OperationServiceImpl</servlet-class>

</servlet><servlet-mapping>

<servlet-name>OperationService</servlet-name><url-pattern>/operation</url-pattern>

</servlet-mapping>

<servlet><servlet-name>ClientService</servlet-name><servlet-class>net.pleso.demo.server.client.ClientServiceImpl</servlet-class>

</servlet><servlet-mapping>

<servlet-name>ClientService</servlet-name><url-pattern>/client</url-pattern>

</servlet-mapping>

Add Required Libraries

Add libraries iBatis, Pleso framework UI & Core and MySQL Java Connector by using Add JAR/Folder …

4. Clean the Project

Problem Delete two files which are not required any more: welcomeGWT.html and demoEntryPoint.java.

Source Migrated ProjectPackages Web Pages

net.pleso.demo.clientFiles welcomeGWT.html

demoEntryPoint.java.Solution Locate files; right click and, then, select Delete.

See the following figure.

5. Changes

5.1.Demo Package IssuesThese correspond to the issues that have been identified while migrating the Pleso demo:

Problem GWT compiler does compile if there are single quotes in messages.Source gwt-pf-ui.jarPackage net.pleso.framework.client.localizationFile messages.propertiesSolution Change all "can't" with "can not" (by using 7-zip).

(Re)archive the library gwt-pf-ui.jar

Problem There is no column named “is_confirmed” in the table “operation”.Source Demo Package (gwt-pf-demo1.tar.gz)Package Not ApplicableFile demo_sql.sqlSolution MySQL database creation script contains this column.

However, add a database column “is_confirmed” .

5.2.Netbeans Related Changes

Problem There is no class named “AuthServiceImpl” which is referenced in the web.xml: <servlet-class>net.pleso.demo.server.auth.AuthServiceImpl </servlet-class>

Source Netbeans migrationPackage Configuration FilesFile web.xmlSolution Change AuthServiceImpl to DemoAuthServiceImpl:

<servlet-class>net.pleso.demo.server.auth.DemoAuthServiceImpl </servlet-class>

Problem URL pattern /auth, /bank, /operation and /client should be preceded by the GWT output directory (gwt.output.dir=/net.pleso.demo.demo).

Source Netbeans migrationPackage Configuration FilesFile web.xmlSolution Perhaps changing the GWT output directory is also a valid solution. However, I

preferred to change four url patterns such as:

<url-pattern>/auth</url-pattern>to <url-pattern>/net.pleso.demo.demo/auth</url-pattern>

Problem Start web page should be demo.html (instead of welcomeGWT.html).Source Netbeans migrationPackage Configuration FilesFile web.xmlSolution Change the welcome file to demo.html:

<welcome-file-list> <welcome-file>demo.html</welcome-file> </welcome-file-list>

Problem Refer to the java script created by GWT compiler in the start WEB page.Source Netbeans migrationPackage Web PagesFile demo.htmlSolution Within the body tag of the demo.html; change

<script language="javascript" src="gwt.js"> </script>to <script language="javascript" src="net.pleso.demo.demo/net.pleso.demo.demo.nocache.js"> </script>

Problem GWT compiler gives an error message for Constants class: [ERROR] class net.pleso.demo.client.localization.Constants_ and Constants are both potential default classes for interface com.google.gwt.i18n.client.Constants.

Source Netbeans migrationPackage net.pleso.demo.client.localizationFile Constants.javaSolution Change Constants.java to AppConstants.java by using Refactor->Rename.

Rename Constants.properties to AppConstants.properties.

Problem Add GWT and Pleso inheritance.Source Netbeans migrationPackage net.pleso.demoFile demo.gwt.xmlSolution Replace

<entry-point class="net.pleso.demo.client.demoEntryPoint"/>With

<!-- Pleso auth library. --><inherits name='net.pleso.auth.plesoauth'/>

<!-- Pleso gwt framework library. --><inherits name='net.pleso.framework.plesoframework'/>

<!-- i18n. --><inherits name="com.google.gwt.i18n.I18N" />

<!-- Specify the app entry point class. --><entry-point class='net.pleso.demo.client.demo'/>

Problem The database column is_confirmed can be null.Source Netbeans migrationPackage net.pleso.demo.server.operationFile OperationServiceImpl.javaSolution Comment out the following two lines in the method public void update(Operation

operation) throws BaseException:

//if (operation.getIs_confirmed().booleanValue())// throw new BaseException("test");

5.3.MySQL Related Changes

Problem MySQL stored functions can not return a set or table. MySQL stored procedures can execute a query but they can not be called in the FROM clause of SELECT statement.

Source Migrated Project - Ibatis ConfigurationPackage net.pleso.demo.server.clientFile client.xmlSolution Only feasible solution that I found is using dynamic queries within the sql mapping

file (Please note that same solution applies to selectCountClient):

<select id="selectClient" resultMap="ClientResult" parameterClass="SelectParams" > Select * From CLIENT_VIEW <dynamic prepend="WHERE"> <isNotNull prepend="AND" property="searchRow.cl_id"> CL_ID = $searchRow.cl_id$ </isNotNull> <isNotNull prepend="AND" property="searchRow.cl_bank_id"> CL_BANK_ID = $searchRow.cl_bank_id$ </isNotNull> <isNotNull prepend="AND" property="searchRow.cl_name"> CL_NAME LIKE '%$searchRow.cl_name$%' </isNotNull> <isNotNull prepend="AND" property="searchRow.bank_name"> BANK_NAME LIKE '%$searchRow.bank_name$%' </isNotNull> <isNotNull prepend="AND" property="searchRow.cl_sex"> CL_SEX LIKE '%$searchRow.cl_sex$%' </isNotNull> <isNotNull prepend="AND" property="searchRow.cl_money_start"> CL_MONEY BETWEEN $searchRow.cl_money_start$ AND $searchRow.cl_money_end$ </isNotNull> <isNotNull prepend="AND" property="searchRow.cl_birthday_start"> ( CL_BIRTHDAY BETWEEN STR_TO_DATE('$searchRow.cl_birthday_start$', '%d-%m-%Y %H:%i') AND STR_TO_DATE('$searchRow.cl_birthday_end$', '%d-%m-%Y %H:%i') ) </isNotNull> </dynamic> <isNotEmpty property="orderByColumnName"> order by $orderByColumnName$ $orderByDirectionString$ </isNotEmpty> limit #limit# offset #offset#</select>

Problem Database connection parameters should be adapted to MySQL serverSource Migrated Project – database connectionPackage net.pleso.demo.serverFile connection.propertiesSolution Use the following parameters (typical parameters):

host = localhostport = 3306database = pfdemo

Problem IBatis should use MySQL java connector.Source Migrated Project - Ibatis ConfigurationPackage net.pleso.demo.serverFile SqlMapConfig.xmlSolution Use the following for MySQL connection:

<transactionManager type="JDBC" commitRequired="true"> <dataSource type="SIMPLE"> <property name="JDBC.Driver" value="com.mysql.jdbc.Driver"/> <property name="JDBC.ConnectionURL" value="jdbc:mysql://${host}:${port}/${database}"/> <property name="JDBC.Username" value="${login}"/> <property name="JDBC.Password" value="${password}"/> </dataSource> </transactionManager>

6. Compilation Issues

Problem GWT compiler gives out of memory while compiling the application.Source Migrated project Package Not ApplicableFile Not ApplicableSolution If you get out of memory error from the GWT compiler, add maxmemory:

<java classpath="${javac.classpath}:${src.dir}" failonerror="true" classname="com.google.gwt.dev.GWTCompiler" fork="true" maxmemory="256M">

7. Create Demo Database

Select Services tab; select your MySQL Server; use right mouse click and select Create Database...:

Provide database name (e.g., pfdemo) and click on the OK button:

Select connection created for new database; use right mouse click and select Connect...:

Provide database user name and password and click on the OK button:

Use right mouse click and select Execute Command …:

Copy the content of the file demo_mysql.sql into the SQL command sheet and click on the “Run SQL” icon:

After successful execution you should see four tables and one view: