Java EE - Introduction - Pierre-Johan CHARTRE pierre-johan.chartre@logica.com

Java Keywords JVM JRE J2SE J2EE JDK Bytecode Object language Object.class JVM Javadoc JRE Manifest.MF ArrayList Main class Java J2SE J2EE JAR Reflection .class JDK UML Bytecode debugger

J2EE Keywords JCP @EJB JMS JSF Transaction Validation JPA @Stateless JSR @MessageDrivenBean @EJB container JMS @SessionScope @Converter @Resource @TransactionAttribute J2EE component JSF Renderer Transaction @ManagedBean @Validator EntityManager CriteriaBuilder Validation @Inject JPA NativeQuery JPQL @NotNull @PersistenceContext

Java Java - A technology invented by Sun Microsystem (RIP) and now an Oracle product. « Write once, run everywhere ». JVM – Java Virtual Machine. It abstracts your OS and executes the Java byte code.

Java JRE – Java Runtime Environment . Set of tools aims to execute a Java program The virtual machine The byte code interpreter and converter into native code The standard Java API JDK – Java Standard Development Kit. It’s your toolbox. It allows to write Java source code and compiles it into byte code. Javac, the java compiler which converts source code (.java) into byte code (.class) Jar, the java archiver. It archives a set of class files into a jar file Javadoc, the documentation generator (abuse it!) Jdb, the java debugger A JRE

Java 2 SE Java Standard Edition. Contains the basics API. It’s desktop computer oriented. A set of basics API Example: Collections

Java 2 EE Specifications of standard API Certifications Different implementation of same API Example: JPA is implemented by Eclipselink, OpenJPA, Hibernate Defined by the Java Community Process (JCP) Certifications Architecture pattern Large scale Multi-tiers (Presentation Logic, Business Logic, Persistence) Scalable Reliable Secure J2EE = an extension of Java SE to facilitate the development of enterprise applications ?

J2EE architecture

J2EE servers ‘’Java EE is a set of specifications implemented by different containers. Containers are Java EE runtime environment that provides certain services to the component they host… ’’ Antonio Goncalves, Beginning Java EE 6 Platform with GlassFish 3 J2EE server = Web container + J2EE implementation Runtime Web container J2EE4 certified J2EE5 J2EE6 Tomcat Yes Open EJB Geronimo = Tomcat + Open EJB JBoss AS IBM Websphere AS Yes >=WAS 8 Glassfish Open source Oracle Glassfish Apache TomEE

J2EE APIs javax.enterprise.inject.* javax.enterprise.context.* javax.validation.* javax.persistence.* javax.transaction.* javax.ejb.* javax.jms.* javax.resources.* javax.servlet.* javax.faces.* javax.faces.component.*

J2EE APIs – The big picture

Core J2EE Patterns = J2EE architecture Design Pattern

To sum up J2EE extends J2SE J2EE is multi-tiers/layered J2EE is a set of specifications, not a set of implementations J2EE server = container + J2EE implementations A J2EE server host J2EE applications