Composition entity mode

Entity mode combination (Composite Entity Pattern) used in the EJB persistence mechanism. A combined entity is an EJB entity bean, on behalf of the graphical object. When updating a combined entity, internal automatically update dependent objects beans, because they are managed by the EJB entity bean. The following is a participant composition entity bean.

• Composition entity (Composite Entity) - which is the main entity bean.It can be coarse, or may contain a coarse-grained object for continuous life cycle.
• Coarse-grained objects (Coarse-Grained Object) - The object contains its object.It has its own life cycle, but also to manage the life cycle of dependent objects.
• Dependent objects (Dependent Object) - dependent objects is a life cycle depends on the coarse-grained object objects continued.
• Strategy (Strategies) - indicate how to implement a combination of strategies entity.

achieve

We will create as a combined entityCompositeEntityobject.CoarseGrainedObjectis a dependent object class contains.

CompositeEntityPatternDemo,our demonstration classes usingClientclass to demonstrate the use of a combination of physical models.

step 1

Create dependent objects.

DependentObject1.java

public class DependentObject1 {
	
   private String data;

   public void setData (String data) {
      this.data = data; 
   } 

   public String getData () {
      return data;
   }
}

DependentObject2.java

public class DependentObject2 {
	
   private String data;

   public void setData (String data) {
      this.data = data; 
   } 

   public String getData () {
      return data;
   }
}

Step 2

Create a coarse-grained object.

CoarseGrainedObject.java

public class CoarseGrainedObject {
   DependentObject1 do1 = new DependentObject1 ();
   DependentObject2 do2 = new DependentObject2 ();

   public void setData (String data1, String data2) {
      do1.setData (data1);
      do2.setData (data2);
   }

   public String [] getData () {
      return new String [] {do1.getData (), do2.getData ()};
   }
}

Step 3

Create a combination of entities.

CompositeEntity.java

public class CompositeEntity {
   private CoarseGrainedObject cgo = new CoarseGrainedObject ();

   public void setData (String data1, String data2) {
      cgo.setData (data1, data2);
   }

   public String [] getData () {
      return cgo.getData ();
   }
}

Step 4

Created using a combination of solid client class.

Client.java

public class Client {
   private CompositeEntity compositeEntity = new CompositeEntity ();

   public void printData () {
      for (int i = 0;. i <compositeEntity.getData () length; i ++) {
         System.out.println ( "Data:" + compositeEntity.getData () [i]);
      }
   }

   public void setData (String data1, String data2) {
      compositeEntity.setData (data1, data2);
   }
}

Step 5

UseClientto demonstrate the use of a combination of physical design patterns.

CompositeEntityPatternDemo.java

public class CompositeEntityPatternDemo {
   public static void main (String [] args) {
       Client client = new Client ();
       client.setData ( "Test", "Data");
       client.printData ();
       client.setData ( "Second Test", "Data1");
       client.printData ();
   }
}

Step 6

Verify output.

Data: Test
Data: Data
Data: Second Test
Data: Data1