showcontext.java

learning java的源代码。书中每个实例都有相关的代码example。

//file: ShowContext.java
package magicbeans;
import javax.swing.*;
import java.beans.beancontext.*;
import java.util.*;

public class ShowContext extends JTabbedPane
                         implements BeanContextProxy {
  BeanContext context;
  BeanContextServices services;
  JList servicesList = new JList(), beansList = new JList(  );

  public ShowContext(  ) {
    addTab( "Beans", new JScrollPane( beansList ) );
    addTab( "Services", new JScrollPane( servicesList ) );
  }

  private BeanContextChildSupport beanContextChild =
    new BeanContextChildSupport(  ) {

    public void initializeBeanContextResources(  )  {
      context= getBeanContext(  );
      try  {
        services = (BeanContextServices)context;
      } catch (ClassCastException ex){/*No BeanContextServices*/}

      updateBeanList(  );
      updateServicesList(  );

      context.addBeanContextMembershipListener(
        new BeanContextMembershipListener(  ) {
          public void childrenAdded(
            BeanContextMembershipEvent e){
            updateBeanList(  );
          }
          public void childrenRemoved(
            BeanContextMembershipEvent e){
            updateBeanList(  );
          }
        } );
      services.addBeanContextServicesListener(
        new BeanContextServicesListener(  ) {
          public void serviceAvailable(
                BeanContextServiceAvailableEvent e ) {
            updateServicesList(  );
          }
          public void serviceRevoked(
                BeanContextServiceRevokedEvent e ) {
            updateServicesList(  );
          }
        } );
    }
  };

  void updateServicesList(  ) {
    if ( services == null )
      return;
    Iterator it = services.getCurrentServiceClasses(  );
    Vector v = new Vector(  );
    while( it.hasNext(  ) )
      v.addElement( it.next(  ) );
    servicesList.setListData( v );
  }
  void updateBeanList(  ) {
    Iterator it = context.iterator(  );
    Vector v = new Vector(  );
    while( it.hasNext(  ) )
      v.addElement( it.next(  ) );
    beansList.setListData( v );
  }

  public BeanContextChild getBeanContextProxy(  ) {
    return beanContextChild;
  }
}