ErrorManager


ErrorManager java.util.logging

Java 1.4

An important feature of the Logging API is that the logging methods called by applications never throw exceptions: it is not reasonable to expect programmers to nest all their logging calls within try/catch blocks, and even if they did, there is no useful way for an application to recover from an exception in the logging subsystem. Since handler classes such as FileHandler are inherently subject to I/O exceptions, the ErrorManager provides a way for a handler to report an exception instead of simply discarding it.

All Handler objects have an instance of ErrorManager associated with them. If an exception occurs in the handler, it passes the exception, along with a message and one of the error code constants defined by ErrorManager to the error( ) method. error( ) writes a message describing the exception to System.err , but does so only the first time it is called: the expectation is that a Handler that throws an exception once will continue to throw the same exception with each subsequent log message, and it is not useful to flood System.err with repeated error messages. You can of course define subclasses of ErrorManager that override error( ) to provide some other reporting mechanism. If you do this, register an instance of your custom ErrorManager by calling the setErrorManager( ) method of your Handler .

 public class  ErrorManager  {  // Public Constructors  public  ErrorManager  ( );  // Public Constants  public static final int  CLOSE_FAILURE  ;  =3  public static final int  FLUSH_FAILURE  ;  =2  public static final int  FORMAT_FAILURE  ;  =5  public static final int  GENERIC_FAILURE  ;  =0  public static final int  OPEN_FAILURE  ;  =4  public static final int  WRITE_FAILURE  ;  =1   // Public Instance Methods  public void  error  (String  msg  , Exception  ex  , int  code  );  synchronized  } 

Passed To

Handler.setErrorManager( )

Returned By

Handler.getErrorManager( )



Java In A Nutshell
Java In A Nutshell, 5th Edition
ISBN: 0596007736
EAN: 2147483647
Year: 2004
Pages: 1220

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