41  * The JDK continues to ship with the older implementation to allow code to run
  42  * that depends on unspecified behavior that differs between the old and new
  43  * implementations. The old implementation will be used if the Java virtual
  44  * machine is started with the system property {@systemProperty
  45  * jdk.net.usePlainDatagramSocketImpl} set to use the old implementation. It may
  46  * also be set in the JDK's network configuration file, located in {@code
  47  * ${java.home}/conf/net.properties}. The value of the property is the string
  48  * representation of a boolean. If set without a value then it defaults to {@code
  49  * true}, hence running with {@code -Djdk.net.usePlainDatagramSocketImpl} or
  50  * {@code -Djdk.net.usePlainDatagramSocketImpl=true} will configure the Java
  51  * virtual machine to use the old implementation. The property and old
  52  * implementation will be removed in a future version.
  53  *
  54  * @author Pavani Diwanji
  55  * @since  1.1
  56  */
  57 
  58 public abstract class DatagramSocketImpl implements SocketOptions {
  59 
  60     /**





  61      * The local port number.
  62      */
  63     protected int localPort;
  64 
  65     /**
  66      * The file descriptor object.
  67      */
  68     protected FileDescriptor fd;
  69 
  70     int dataAvailable() {
  71         // default impl returns zero, which disables the calling
  72         // functionality
  73         return 0;
  74     }
  75 
  76     /**
  77      * Creates a datagram socket.
  78      * @throws    SocketException if there is an error in the
  79      * underlying protocol, such as a TCP error.
  80      */

  41  * The JDK continues to ship with the older implementation to allow code to run
  42  * that depends on unspecified behavior that differs between the old and new
  43  * implementations. The old implementation will be used if the Java virtual
  44  * machine is started with the system property {@systemProperty
  45  * jdk.net.usePlainDatagramSocketImpl} set to use the old implementation. It may
  46  * also be set in the JDK's network configuration file, located in {@code
  47  * ${java.home}/conf/net.properties}. The value of the property is the string
  48  * representation of a boolean. If set without a value then it defaults to {@code
  49  * true}, hence running with {@code -Djdk.net.usePlainDatagramSocketImpl} or
  50  * {@code -Djdk.net.usePlainDatagramSocketImpl=true} will configure the Java
  51  * virtual machine to use the old implementation. The property and old
  52  * implementation will be removed in a future version.
  53  *
  54  * @author Pavani Diwanji
  55  * @since  1.1
  56  */
  57 
  58 public abstract class DatagramSocketImpl implements SocketOptions {
  59 
  60     /**
  61      * Constructor for subclasses to call.
  62      */
  63     public DatagramSocketImpl() {}
  64 
  65     /**
  66      * The local port number.
  67      */
  68     protected int localPort;
  69 
  70     /**
  71      * The file descriptor object.
  72      */
  73     protected FileDescriptor fd;
  74 
  75     int dataAvailable() {
  76         // default impl returns zero, which disables the calling
  77         // functionality
  78         return 0;
  79     }
  80 
  81     /**
  82      * Creates a datagram socket.
  83      * @throws    SocketException if there is an error in the
  84      * underlying protocol, such as a TCP error.
  85      */