Javaone 2010 report

Tadaya Tsuyukubo tw: @ttddyy

http://bit.ly/ttddyy_javaone2010

Agenda

• pics• java roadmap

o projectso featureo release plan

• summary of Java EE sessions• case studies

o mint.como ebayo etc.

• other tech sessions

Oracle OpenWorld+

JavaOne

Year 2010 Sep 19-23San Francisco

Java 7, 8

• Productivity• Performance• Modularity

o Project Coin

Productivity with More Concise Codeo Project Lambda

Closures for Javao Project Jigsaw

The Modular Java Platform

NIO2(jsr203), Concurrency and Collections updates(jsr166y), JDBC4.1, etc.

Project Coin

• Diamond Map<String, List<Integer>> map = new HashMap<>()

• Try-with-resources try( InputStream is = new FileInputStream(in); OutputStream os = new FileOutputStream(out) ) { ... } catch (Exception e) { ... }

• Strings in Switch• Improved integral literals• Vargs warnings• Multi-catch & precise rethrow

Project Lambda

• SAM (Single Abstract Method)

Collections.sort( data, #( int a, int b ){ a.length() - b.length() } ); double max = students.filter( #{ s -> s.gradYear == 2010 }) .map( #{ s -> s.score }) .max();

• Method Reference

Collections.sortBy(students, #Student.getName);

Project Jigsaw

• eliminate the class path• light weight memory foot print

• module-info.javao meta data (module dependency info)

@Version("1.0") @ImportModules( {

@ImportModule(name="java.se"), @ImportModule(name="com.foo.OrderProcessingService"), @ImportModule(name="com.bar.PrintService") } ) @MainClass("hello.HelloWorld") module hello;

etc.

• Value Class value class Foo { property Foo parent; property String name; }

• JVMo upto 32G Heap Compactiono NUMA (Non-Uniform Memory Access)o G1GC (Garbage First GC)

• Integrate JRockit to HotSpot o Nondisruptive, Scalable, High Performance VM

Java Release Plan

Plan B• Java7 (mid 2011)

o most of "Project Coin"o New I/O APIso Fork/Join Frameworko InvokeDynamico etc.

• Java8 (late 2012)o Project Lambdao Project Jigsawo Rest of Project Coino etc.

Web related tech sessions

• EJB3 features (Transaction, Business Tier)o Bean Validation (JSR303)

Hibernate Validatoro CDI(Contexts and Dependency Injection) (JSR299)

@Inject, @Model, @Singleton, @Stateless, etc.o JPA 2.0 (JSR317)

• For Java6

o Common Annotation for the Java Platform (JSR250) @Resource, @PostConstruct, @PreDestroy

Annotation Jam

@Secure@Transactional@RequestScoped@Named class SomeClass { ......}

@BusinessLogic class SomeClass {}

use customized stereotype

Web session summary

• new features are mostly available in springo using spring is a correct choiceo giving more confusion to developers

• EJB containers are requiredo mostly commercialo still heavy weight

Advantage of using EJB • session clustering• remoting• commercial support?• vendor specific tools

spring is much better!! - lightweight - integration to other tech

Case Study (mint.com)

• Free personal financial management web• 2billion financial transaction• 10m+ transaction per day

Architecture • spring + hibernate• memcached• intensive use of AOP

DB Scaling

NOSQL• lose integrity ==> not best fit

User ID based sharding• Hierarchical data model• Logical database separation

o user data & non user data• put user_id to all hierarchical entities (user data)

o every user data is exclusive and have locality

Implementation

Minimize infrastructure sharding info to implementation context• annotation • AOP

@MintUserdataclass UserService { .... }

@MintCommondataclass MasterDataService { .... }

switch SessionFactory, Datasource by AOP based on the annotation

Monitoring

• collect data from real prod requestso viewed page, traffic, behavioro cache statisticso hibernate statisticso thread pool & queue size

• monitoring overhead must be low

o aggregate results in memoryo persist periodically

Monitoring Impl

monitor all spring beans• AOP autoproxy all beans, no code change• All methods (request-response lifecycle) can be drilldown

• build custom tool (80/20 rule)• intensive use of AOP to monitor application error logs• log messages are parametrized, centeralized• web tool to easily search/parse errors

o like splunk

~/account.htm?id=1 100ms

AccountController#info() 10ms

AccountService#getInfo() 20ms

AccountDao#getInfoById() 70ms

Security & How to reduce Bug

Use hibernate to enforce isolation• use AOP or hibernate callback

o if data tries to access data that doesn't belong to the user, throws exception

Detect crosstalk (multi thread test)• run test class with multiple user (sequential, multithread)

Case Study (eBay)

• 10bil requests per day• 10K java servers

• partition everything• asynchronous everywhere• automate everything• everything fails• embrace inconsistency

• expect (r)evolution• dependencies matters• respect authority (data)• never enough data• custom infrastructure

Case Study (Sinapto)

Online Poker in Italy3000 concurrent players

Architecture• Vertical, Horizontal partitioning (table, tournament)• asynchronous (event driven)• pass around status object

Case Study (Caché)

Specialized to write huge data example:

3-D map of Galaxy monitor 1billion stars, more & more newly found ones (Peta byte level data) stock market trading information government, healthcare, financial industry

solution:o wrote DB : 130+K sustained inserts per sec

JDBC: runs over tcp/ip (even locally) use JNI (Java Native Interface) Store multi dimensional data XEP: serialize & store MDS: Monitoring & Deiscovery Service

NOSQL

• This does not replace RDBMS• Suit for representing data in a simple datastructure

o High Scalabilityo Flexible modificationo Specialized process

Characteristic• no join• mostly search data by single rowkey• eventual consistency

Data Model Eventual Consistency• no transaction, no consistency

o application needs to handle consistency

Example: For column based DB, there is no association table, and no

cascade delete. When parent data is removed, child data needs to deleted

by application

RDBMS NoSQL

relational column, KV, etc.

Testing

Unit Test• selenium IDE• junit• mock

Integration Test• starting container at beginning of test in code

Functional Programming

"OO is better to project our world structure FP excels at actual coding of the algorithm"

Use OO to build classes Use FP to implement methods

Java 7, 8 will have FP(closure) feature. (lambda project)

Conclusionspring is the best!! Java future roadmap, Case Studies javaone "2010" Technical sessions...• Spring One• Server Side • No Fluff, Just Stuff

met jp java community