Module java.logging

Class SocketHandler

public class SocketHandler extends StreamHandler
Simple network logging Handler.

LogRecords are published to a network stream connection. By default the XMLFormatter class is used for formatting.

Configuration: By default each SocketHandler is initialized using the following LogManager configuration properties where <handler-name> refers to the fully-qualified class name of the handler. If properties are not defined (or have invalid values) then the specified default values are used.

  • <handler-name>.level specifies the default level for the Handler (defaults to Level.ALL).
  • <handler-name>.filter specifies the name of a Filter class to use (defaults to no Filter).
  • <handler-name>.formatter specifies the name of a Formatter class to use (defaults to java.util.logging.XMLFormatter).
  • <handler-name>.encoding the name of the character set encoding to use (defaults to the default platform encoding).
  • <handler-name>.host specifies the target host name to connect to (no default).
  • <handler-name>.port specifies the target TCP port to use (no default).

For example, the properties for SocketHandler would be:

  • java.util.logging.SocketHandler.level=INFO
  • java.util.logging.SocketHandler.formatter=java.util.logging.SimpleFormatter

For a custom handler, e.g., the properties would be:


The output IO stream is buffered, but is flushed after each LogRecord is written.

  • Constructor Details

    • SocketHandler

      public SocketHandler() throws IOException
      Create a SocketHandler, using only LogManager properties (or their defaults).
      IllegalArgumentException - if the host or port are invalid or are not specified as LogManager properties.
      IOException - if we are unable to connect to the target host and port.
    • SocketHandler

      public SocketHandler(String host, int port) throws IOException
      Construct a SocketHandler using a specified host and port. The SocketHandler is configured based on LogManager properties (or their default values) except that the given target host and port arguments are used. If the host argument is empty, but not null String then the localhost is used.
      host - target host.
      port - target port.
      IllegalArgumentException - if the host or port are invalid.
      IOException - if we are unable to connect to the target host and port.
  • Method Details

    • close

      public void close() throws SecurityException
      Close this output stream.
      close in class StreamHandler
      SecurityException - if a security manager exists and if the caller does not have LoggingPermission("control").
    • publish

      public void publish(LogRecord record)
      Format and publish a LogRecord.
      publish in class StreamHandler
      record - description of the log event. A null record is silently ignored and is not published