bettersharedobject.java

java 完全探索的随书源码

public class BetterSharedObject extends SharedObject
{

  // The private shared data variable
  private Integer sharedData = null;
  private boolean dataAvailable = false;

  // Default Constructor
  public BetterSharedObject( int initialValue )
  {
    super( initialValue );
    // Initialize the shared object value to something
    sharedData = new Integer( initialValue );
  }

  // The produced will call this method to update the data
  public synchronized void setSharedData( int newData )
  {
    if ( dataAvailable )
    {
      try
      {
        wait();
      }
      catch( InterruptedException ex )
      {}
    }

    System.out.println( "Shared Object - New Value Set: " + newData );
    sharedData = new Integer( newData );
    System.out.println( "Send notification that its ok to read new data" );
    dataAvailable = true;
    notifyAll();
  }

  // The consumer will call this method to get the new data
  public synchronized Integer getSharedData()
  {
    if ( !dataAvailable )
    {
      try
      {
        wait();
      }
      catch( InterruptedException ex )
      {
        System.out.println( "Got notification that it was ok to read new data" );
      }
    }
    dataAvailable = false;
    notifyAll();
    return sharedData;
  }
}