Class LogContext

  • All Implemented Interfaces:
    java.lang.AutoCloseable, Protectable

    public final class LogContext
    extends java.lang.Object
    implements Protectable, java.lang.AutoCloseable
    A logging context, for producing isolated logging environments.
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void addCloseHandler​(java.lang.AutoCloseable closeHandler)
      Adds a handler invoked during the close of this log context.
      void close()  
      static LogContext create()
      Create a new log context.
      static LogContext create​(boolean strong)
      Create a new log context.
      protected void decrementRef​(java.lang.String name)  
      void disableAccess()
      Disable previous access to the object for modifications on the current thread.
      void enableAccess​(java.lang.Object protectKey)
      Enable access to the object for modifications on the current thread.
      <V> V getAttachment​(java.lang.String loggerName, Logger.AttachmentKey<V> key)
      Get a logger attachment for a logger name, if it exists.
      java.util.Set<java.lang.AutoCloseable> getCloseHandlers()
      Gets the current close handlers associated with this log context.
      java.util.logging.Level getLevelForName​(java.lang.String name)
      Get the level for a name.
      static LogContext getLogContext()
      Get the currently active log context.
      static LogContextSelector getLogContextSelector()
      Returns the currently set log context selector.
      Logger getLogger​(java.lang.String name)
      Get a logger with the given name from this logging context.
      Logger getLoggerIfExists​(java.lang.String name)
      Get a logger with the given name from this logging context, if a logger node exists at that location.
      java.util.Enumeration<java.lang.String> getLoggerNames()
      Returns an enumeration of the logger names that have been created.
      java.util.logging.LoggingMXBean getLoggingMXBean()
      Get the LoggingMXBean associated with this log context.
      static LogContext getSystemLogContext()
      Get the system log context.
      protected void incrementRef​(java.lang.String name)  
      void protect​(java.lang.Object protectionKey)
      Protect this object from modifications.
      void registerLevel​(java.util.logging.Level level)
      Register a level instance with this log context.
      void setCloseHandlers​(java.util.Collection<java.lang.AutoCloseable> closeHandlers)
      Clears any current close handlers associated with log context, then adds the handlers to be invoked during the close of this log context.
      static void setLogContextSelector​(LogContextSelector newSelector)
      Set a new log context selector.
      void unprotect​(java.lang.Object protectionKey)
      Allows the object to be modified if the protectionKey matches the key used to protect the object.
      void unregisterLevel​(java.util.logging.Level level)
      Unregister a previously registered level.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Field Detail

      • DEFAULT_LOG_CONTEXT_SELECTOR

        public static final LogContextSelector DEFAULT_LOG_CONTEXT_SELECTOR
        The default log context selector, which always returns the system log context.
    • Method Detail

      • create

        public static LogContext create​(boolean strong)
        Create a new log context. If a security manager is installed, the caller must have the "createLogContext" RuntimePermission to invoke this method.
        Parameters:
        strong - true if the context should use strong references, false to use (default) weak references for automatic logger GC
        Returns:
        a new log context
      • create

        public static LogContext create()
        Create a new log context. If a security manager is installed, the caller must have the "createLogContext" RuntimePermission to invoke this method.
        Returns:
        a new log context
      • getLogger

        public Logger getLogger​(java.lang.String name)
        Get a logger with the given name from this logging context.
        Parameters:
        name - the logger name
        Returns:
        the logger instance
        See Also:
        LogManager.getLogger(String)
      • getLoggerIfExists

        public Logger getLoggerIfExists​(java.lang.String name)
        Get a logger with the given name from this logging context, if a logger node exists at that location.
        Parameters:
        name - the logger name
        Returns:
        the logger instance, or null if no such logger node exists
      • getAttachment

        public <V> V getAttachment​(java.lang.String loggerName,
                                   Logger.AttachmentKey<V> key)
        Get a logger attachment for a logger name, if it exists.
        Type Parameters:
        V - the attachment value type
        Parameters:
        loggerName - the logger name
        key - the attachment key
        Returns:
        the attachment or null if the logger or the attachment does not exist
      • getLoggingMXBean

        public java.util.logging.LoggingMXBean getLoggingMXBean()
        Get the LoggingMXBean associated with this log context.
        Returns:
        the LoggingMXBean instance
      • getLevelForName

        public java.util.logging.Level getLevelForName​(java.lang.String name)
                                                throws java.lang.IllegalArgumentException
        Get the level for a name.
        Parameters:
        name - the name
        Returns:
        the level
        Throws:
        java.lang.IllegalArgumentException - if the name is not known
      • registerLevel

        public void registerLevel​(java.util.logging.Level level)
        Register a level instance with this log context. The level can then be looked up by name. Only a weak reference to the level instance will be kept. Any previous level registration for the given level's name will be overwritten.
        Parameters:
        level - the level to register
      • unregisterLevel

        public void unregisterLevel​(java.util.logging.Level level)
        Unregister a previously registered level. Log levels that are not registered may still be used, they just will not be findable by name.
        Parameters:
        level - the level to unregister
      • getSystemLogContext

        public static LogContext getSystemLogContext()
        Get the system log context.
        Returns:
        the system log context
      • getLogContext

        public static LogContext getLogContext()
        Get the currently active log context.
        Returns:
        the currently active log context
      • setLogContextSelector

        public static void setLogContextSelector​(LogContextSelector newSelector)
        Set a new log context selector. If a security manager is installed, the caller must have the "setLogContextSelector" RuntimePermission to invoke this method.
        Parameters:
        newSelector - the new selector.
      • getLogContextSelector

        public static LogContextSelector getLogContextSelector()
        Returns the currently set log context selector.
        Returns:
        the log context selector
      • protect

        public void protect​(java.lang.Object protectionKey)
                     throws java.lang.SecurityException
        Description copied from interface: Protectable
        Protect this object from modifications.
        Specified by:
        protect in interface Protectable
        Parameters:
        protectionKey - the key used to protect the object.
        Throws:
        java.lang.SecurityException - if the object is already protected.
      • unprotect

        public void unprotect​(java.lang.Object protectionKey)
                       throws java.lang.SecurityException
        Description copied from interface: Protectable
        Allows the object to be modified if the protectionKey matches the key used to protect the object.
        Specified by:
        unprotect in interface Protectable
        Parameters:
        protectionKey - the key used to protect the object.
        Throws:
        java.lang.SecurityException - if the object is protected and the key doesn't match.
      • enableAccess

        public void enableAccess​(java.lang.Object protectKey)
                          throws java.lang.SecurityException
        Description copied from interface: Protectable
        Enable access to the object for modifications on the current thread.
        Specified by:
        enableAccess in interface Protectable
        Parameters:
        protectKey - the key used to protect modifications.
        Throws:
        java.lang.SecurityException
      • disableAccess

        public void disableAccess()
        Description copied from interface: Protectable
        Disable previous access to the object for modifications on the current thread.
        Specified by:
        disableAccess in interface Protectable
      • close

        public void close()
                   throws java.lang.Exception
        Specified by:
        close in interface java.lang.AutoCloseable
        Throws:
        java.lang.Exception
      • getLoggerNames

        public java.util.Enumeration<java.lang.String> getLoggerNames()
        Returns an enumeration of the logger names that have been created. This does not return names of loggers that may have been garbage collected. Logger names added after the enumeration has been retrieved may also be added to the enumeration.
        Returns:
        an enumeration of the logger names
        See Also:
        LogManager.getLoggerNames()
      • addCloseHandler

        public void addCloseHandler​(java.lang.AutoCloseable closeHandler)
        Adds a handler invoked during the close of this log context. The close handlers will be invoked in the order they are added.

        The loggers associated with this context will always be closed.

        Parameters:
        closeHandler - the close handler to use
      • getCloseHandlers

        public java.util.Set<java.lang.AutoCloseable> getCloseHandlers()
        Gets the current close handlers associated with this log context.
        Returns:
        the current close handlers
      • setCloseHandlers

        public void setCloseHandlers​(java.util.Collection<java.lang.AutoCloseable> closeHandlers)
        Clears any current close handlers associated with log context, then adds the handlers to be invoked during the close of this log context. The close handlers will be invoked in the order they are added.

        The loggers associated with this context will always be closed.

        Parameters:
        closeHandlers - the close handlers to use
      • incrementRef

        protected void incrementRef​(java.lang.String name)
      • decrementRef

        protected void decrementRef​(java.lang.String name)