Source of BlockingBuffer.java


  1: // Fig. 23.15: BlockingBuffer.java
  2: // Class synchronizes access to a blocking buffer.
  3: import java.util.concurrent.ArrayBlockingQueue;
  4: 
  5: public class BlockingBuffer implements Buffer
  6: {
  7:    private ArrayBlockingQueue<Integer> buffer;
  8: 
  9:    public BlockingBuffer()
 10:    {
 11:       buffer = new ArrayBlockingQueue<Integer>( 3 );
 12:    } // end BlockingBuffer constructor
 13:    
 14:    // place value into buffer
 15:    public void set( int value )
 16:    {
 17:       try
 18:       {
 19:          buffer.put( value ); // place value in circular buffer
 20:          System.out.printf( "%s%2d\t%s%d\n", "Producer writes ", value,
 21:             "Buffers occupied: ", buffer.size() );
 22:       } // end try
 23:       catch ( Exception exception )
 24:       {
 25:          exception.printStackTrace();
 26:       } // end catch
 27:    } // end method set
 28: 
 29:    // return value from buffer
 30:    public int get()
 31:    {
 32:       int readValue = 0; // initialize value read from buffer
 33: 
 34:       try
 35:       {
 36:          readValue = buffer.take(); // remove value from circular buffer
 37:          System.out.printf( "%s %2d\t%s%d\n", "Consumer reads ", readValue, 
 38:             "Buffers occupied: ", buffer.size() );
 39:       } // end try
 40:       catch ( Exception exception )
 41:       {
 42:          exception.printStackTrace();
 43:       } // end catch
 44: 
 45:       return readValue;
 46:    } // end method get
 47: } // end class BlockingBuffer
 48: 
 49: 
 50: /**************************************************************************
 51:  * (C) Copyright 1992-2005 by Deitel & Associates, Inc. and               *
 52:  * Pearson Education, Inc. All Rights Reserved.                           *
 53:  *                                                                        *
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