courseejb.java

< J2EE应用开发详解>>一书全部的源代码. 本书基于J2EE 1．4平台

package com.j2ee14.ch17;

import java.rmi.RemoteException;
import javax.ejb.*;
import java.util.*;

public abstract class CourseEJB implements EntityBean
{
    /**
     * Attributes declaration
    */
    public EntityContext EJB_Context;
    
    /**
     * @J2EE_METHOD  --  CourseEJB
     */
    public CourseEJB    ()  
    { 

    }
    
    /**
     * @J2EE_METHOD  --  ejbCreate
     * Matching method of the create() method of the bean's home interface. The container
     * invokes an ejbCreate method to create an entity object. It executes in the transaction
     * context determined by the transaction attribute of the matching create() method.
     * @throws javax.ejb.CreateException
     */
    public String ejbCreate    (String pk) throws CreateException 
    { 
			this.setId(pk);
			return null;
    }
    
    /**
     * @J2EE_METHOD  --  ejbPostCreate
     * Matching method of ejbCreate. The container invokes the matching ejbPostCreate method
     * on an instance after it invokes the ejbCreate method with the same arguments. It
     * executes in the same transaction context as that of the matching ejbCreate method.
     * @throws javax.ejb.CreateException
     */
    public void ejbPostCreate    (String pk) throws CreateException 
    { 

    }
    
    /**
     * @J2EE_METHOD  --  ejbActivate
     * A container invokes this method when the instance is taken out of the pool of available
     * instances to become associated with a specific EJB object. This method transitions
     * the instance to the ready state. This method executes in an unspecified transaction
     * context.
     */
    public void ejbActivate    ()  
    { 

    }
    
    /**
     * @J2EE_METHOD  --  ejbPassivate
     * A container invokes this method on an instance before the instance becomes disassociated
     * with a specific EJB object. After this method completes, the container will place
     * the instance into the pool of available instances. This method executes in an unspecified
     * transaction context.
     */
    public void ejbPassivate    ()  
    { 

    }
    
    /**
     * @J2EE_METHOD  --  ejbLoad
     * A container invokes this method to instruct the instance to synchronize its state
     * by loading it from the underlying database. This method always executes in the transaction
     * context determined by the value of the transaction attribute in the deployment descriptor.
     */
    public void ejbLoad    ()  
    { 

    }
    
    /**
     * @J2EE_METHOD  --  ejbStore
     * A container invokes this method to instruct the instance to synchronize its state
     * by storing it to the underlying database. This method always executes in the transaction
     * context determined by the value of the transaction attribute in the deployment descriptor.
     */
    public void ejbStore    ()  
    { 

    }
    
    /**
     * @J2EE_METHOD  --  ejbRemove
     * A container invokes this method before it removes the EJB object that is currently
     * associated with the instance. It is invoked when a client invokes a remove operation
     * on the enterprise Bean's home or remote interface. It transitions the instance from
     * the ready state to the pool of available instances. It is called in the transaction
     * context of the remove operation.
     * @throws javax.ejb.RemoveException
     */
    public void ejbRemove    () throws RemoveException 
    { 

    }
    
    /**
     * @J2EE_METHOD  --  setEntityContext
     * Set the associated entity context. The container invokes this method on an instance
     * after the instance has been created. This method is called in an unspecified transaction
     * context. 
     */
    public void setEntityContext    (EntityContext ctx)  
    { 
		this.EJB_Context=ctx;
    }
    
    /**
     * @J2EE_METHOD  --  unsetEntityContext
     * Unset the associated entity context. The container calls this method before removing
     * the instance. This is the last method that the container invokes on the instance.
     * The Java garbage collector will  invoke the finalize() method on the instance. It
     * is called in an unspecified transaction context.
     */
    public void unsetEntityContext    ()  
    { 
		this.EJB_Context=null;
    }
    
    /**
     * @J2EE_METHOD  --  getName
     */
    public abstract String getName    (); 
    
    /**
     * @J2EE_METHOD  --  setName
     */
    public abstract void setName    (String newName); 
    
    /**
     * @J2EE_METHOD  --  getId
     */
    public abstract String getId    (); 
    
    /**
     * @J2EE_METHOD  --  setId
     */
    public abstract void setId    (String newId); 
    
    /**
     * @J2EE_METHOD  --  getStudents
     */
    public abstract java.util.Collection getStudents    (); 
    
    /**
     * @J2EE_METHOD  --  setStudents
     */
    public abstract void setStudents    (java.util.Collection newStudents); 
    
     //业务方法
    public java.util.Collection getAllStudentsId()
    {
    	Collection ret=new ArrayList();
    	Iterator it=this.getStudents().iterator();
		   
		    while(it.hasNext())
		    {
		      StudentLocal stud=(StudentLocal)it.next();
		      ret.add(stud.getId());
		      
		    }
		    return ret;
    }   
  
}