C M P   2 . 0  

Chapter  

9 

9. CMP 2.0 

Container Managed Persistence by Dain Sundstrom 

Entity Basics 

JBossCMP is a powerful persistence engine compliant with the EJB 2.0 CMP 2.0 

specification.  Although several new features have been added, the basic entity bean 

structure has not changed much in CMP 2.0.  One small, yet very important, change is a 

CMP field is longer declared using a class field in the bean implementation class, but instead 

is declared with a set of abstract accessor methods. Abstract accessors are similar to 

JavaBean property accessors, except no implementation is given. The following listings 

declare the local home, local, and bean implementation class with gangsterId, name, 

nickName, and badness cmp fields: 

// Gangster Local Home Interface  

public interface GangsterHome extends 

EJBLocalHome

 {

   Gangster create(Integer id, String name, String nickName) throws CreateException; 

   Gangster findByPrimaryKey(Integer id) throws FinderException; 

} 

Listing 9 1, Entity Local Home Interface 

// Gangster Local Interface 

public interface Gangster extends 

EJBLocalObject

 {

   Integer getGangsterId(); 

   String getName(); 

   String getNickName(); 

   void setNickName(String nickName); 

} 

Listing 9 2, Entity Local Interface 

// Gangster Implementation Class 

public 

abstract

 class GangsterBean implements EntityBean

 {

   private EntityContext ctx; 

   private Category log = Category.getInstance(getClass()); 

   public Integer ejbCreate(Integer id, String name, String nickName)  

         throws CreateException { 

      log.info("Creating Gangster " + id + "  " + nickName + "  "+ name); 

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