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Summary: Ctors | Methods | Inherited Methods | [Expand All]

Added in API level 1

public class

MemoryHandler

extends Handler

java.lang.Object
↳	java.util.logging.Handler
	↳	java.util.logging.MemoryHandler

Class Overview

A Handler put the description of log events into a cycled memory buffer.

Mostly this MemoryHandler just puts the given LogRecord into the internal buffer and doesn't perform any formatting or any other process. When the buffer is full, the earliest buffered records will be discarded.

Every MemoryHandler has a target handler, and push action can be triggered so that all buffered records will be output to the target handler and normally the latter will publish the records. After the push action, the buffer will be cleared.

The push method can be called directly, but will also be called automatically if a new LogRecord is added that has a level greater than or equal to than the value defined for the property java.util.logging.MemoryHandler.push.

MemoryHandler will read following LogManager properties for initialization, if given properties are not defined or has invalid values, default value will be used.

java.util.logging.MemoryHandler.filter specifies the Filter class name, defaults to no Filter.
java.util.logging.MemoryHandler.level specifies the level for this Handler, defaults to Level.ALL.
java.util.logging.MemoryHandler.push specifies the push level, defaults to level.SEVERE.
java.util.logging.MemoryHandler.size specifies the buffer size in number of LogRecord, defaults to 1000.
java.util.logging.MemoryHandler.target specifies the class of the target Handler, no default value, which means this property must be specified either by property setting or by constructor.

Summary

Public Constructors
	MemoryHandler() Default constructor, construct and init a `MemoryHandler` using `LogManager` properties or default values.
	MemoryHandler(Handler target, int size, Level pushLevel) Construct and init a `MemoryHandler` using given target, size and push level, other properties using `LogManager` properties or default values.

Public Methods
void	close() Close this handler and target handler, free all associated resources.
void	flush() Call target handler to flush any buffered output.
Level	getPushLevel() Return the push level.
boolean	isLoggable(LogRecord record) Check if given `LogRecord` would be put into this `MemoryHandler`'s internal buffer.
synchronized void	publish(LogRecord record) Put a given `LogRecord` into internal buffer.
void	push() Triggers a push action to output all buffered records to the target handler, and the target handler will publish them.
void	setPushLevel(Level newLevel) Set the push level.

[Expand]

Inherited Methods

From class java.util.logging.Handler

abstract void	close() Closes this handler.
abstract void	flush() Flushes any buffered output.
String	getEncoding() Gets the character encoding used by this handler, `null` for default encoding.
ErrorManager	getErrorManager() Gets the error manager used by this handler to report errors during logging.
Filter	getFilter() Gets the filter used by this handler.
Formatter	getFormatter() Gets the formatter used by this handler to format the logging messages.
Level	getLevel() Gets the logging level of this handler, records with levels lower than this value will be dropped.
boolean	isLoggable(LogRecord record) Determines whether the supplied log record needs to be logged.
abstract void	publish(LogRecord record) Accepts a logging request and sends it to the the target.
void	reportError(String msg, Exception ex, int code) Reports an error to the error manager associated with this handler, `ErrorManager` is used for that purpose.
void	setEncoding(String encoding) Sets the character encoding used by this handler, `null` indicates a default encoding.
void	setErrorManager(ErrorManager newErrorManager) Sets the error manager for this handler.
void	setFilter(Filter newFilter) Sets the filter to be used by this handler.
void	setFormatter(Formatter newFormatter) Sets the formatter to be used by this handler.
void	setLevel(Level newLevel) Sets the logging level of the messages logged by this handler, levels lower than this value will be dropped.

From class java.lang.Object

Object	clone() Creates and returns a copy of this `Object`.
boolean	equals(Object o) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of `Class` that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait() Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.
final void	wait(long millis, int nanos) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait(long millis) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.

Public Constructors

public MemoryHandler ()

Added in API level 1

Default constructor, construct and init a MemoryHandler using LogManager properties or default values.

Throws

RuntimeException	if property value are invalid and no default value could be used.

public MemoryHandler (Handler target, int size, Level pushLevel)

Added in API level 1

Construct and init a MemoryHandler using given target, size and push level, other properties using LogManager properties or default values.

Parameters

target	the given `Handler` to output
size	the maximum number of buffered `LogRecord`, greater than zero
pushLevel	the push level

Throws

IllegalArgumentException	if `size <= 0`
RuntimeException	if property value are invalid and no default value could be used.

Public Methods

public void close ()

Added in API level 1

Close this handler and target handler, free all associated resources.

public void flush ()

Added in API level 1

Call target handler to flush any buffered output. Note that this doesn't cause this MemoryHandler to push.

public Level getPushLevel ()

Added in API level 1

Return the push level.

Returns

the push level

public boolean isLoggable (LogRecord record)

Added in API level 1

Check if given LogRecord would be put into this MemoryHandler's internal buffer.

The given LogRecord is loggable if and only if it has appropriate level and it pass any associated filter's check.

Note that the push level is not used for this check.

Parameters

record	the given `LogRecord`

Returns

the given LogRecord if it should be logged, false if LogRecord is null.

public synchronized void publish (LogRecord record)

Added in API level 1

Put a given LogRecord into internal buffer. If given record is not loggable, just return. Otherwise it is stored in the buffer. Furthermore if the record's level is not less than the push level, the push action is triggered to output all the buffered records to the target handler, and the target handler will publish them.

Parameters

record	the log record

public void push ()

Added in API level 1

Triggers a push action to output all buffered records to the target handler, and the target handler will publish them. Then the buffer is cleared.

public void setPushLevel (Level newLevel)

Added in API level 1

Set the push level. The push level is used to check the push action triggering. When a new LogRecord is put into the internal buffer and its level is not less than the push level, the push action will be triggered. Note that set new push level won't trigger push action.

Parameters

newLevel	the new level to set.

Results

Interfaces

Classes

MemoryHandler

Class Overview

Summary

Public Constructors

public MemoryHandler ()

Throws

public MemoryHandler (Handler target, int size, Level pushLevel)

Parameters

Throws

Public Methods

public void close ()

public void flush ()

public Level getPushLevel ()

Returns

public boolean isLoggable (LogRecord record)

Parameters

Returns

public synchronized void publish (LogRecord record)

Parameters

public void push ()

public void setPushLevel (Level newLevel)

Parameters