Class StreamHandler
- java.lang.Object
-
- java.util.logging.Handler
-
- java.util.logging.StreamHandler
- Direct Known Subclasses:
-
ConsoleHandler
,FileHandler
,SocketHandler
public class StreamHandler extends Handler
Stream based logging Handler
.
This is primarily intended as a base class or support class to be used in implementing other logging Handlers
.
LogRecords
are published to a given java.io.OutputStream
.
Configuration: By default each StreamHandler
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 toLevel.INFO
). - <handler-name>.filter specifies the name of a
Filter
class to use (defaults to noFilter
). - <handler-name>.formatter specifies the name of a
Formatter
class to use (defaults tojava.util.logging.SimpleFormatter
). - <handler-name>.encoding the name of the character set encoding to use (defaults to the default platform encoding).
For example, the properties for StreamHandler
would be:
- java.util.logging.StreamHandler.level=INFO
- java.util.logging.StreamHandler.formatter=java.util.logging.SimpleFormatter
For a custom handler, e.g. com.foo.MyHandler, the properties would be:
- com.foo.MyHandler.level=INFO
- com.foo.MyHandler.formatter=java.util.logging.SimpleFormatter
- Since:
- 1.4
Constructor Summary
Constructor | Description |
---|---|
StreamHandler() | Create a |
StreamHandler(OutputStream out,
Formatter formatter) | Create a |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
void | close() | Close the current output stream. |
void | flush() | Flush any buffered messages. |
boolean | isLoggable(LogRecord record) | Check if this |
void | publish(LogRecord record) | Format and publish a |
void | setEncoding(String encoding) | Set (or change) the character encoding used by this |
protected void | setOutputStream(OutputStream out) | Change the output stream. |
Methods declared in class java.util.logging.Handler
getEncoding, getErrorManager, getFilter, getFormatter, getLevel, reportError, setErrorManager, setFilter, setFormatter, setLevel
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Constructor Detail
StreamHandler
public StreamHandler()
Create a StreamHandler
, with no current output stream.
StreamHandler
public StreamHandler(OutputStream out, Formatter formatter)
Create a StreamHandler
with a given Formatter
and output stream.
- Parameters:
-
out
- the target output stream -
formatter
- Formatter to be used to format output
Method Detail
setOutputStream
protected void setOutputStream(OutputStream out) throws SecurityException
Change the output stream.
If there is a current output stream then the Formatter
's tail string is written and the stream is flushed and closed. Then the output stream is replaced with the new output stream.
- Parameters:
-
out
- New output stream. May not be null. - Throws:
-
SecurityException
- if a security manager exists and if the caller does not haveLoggingPermission("control")
.
setEncoding
public void setEncoding(String encoding) throws SecurityException, UnsupportedEncodingException
Set (or change) the character encoding used by this Handler
.
The encoding should be set before any LogRecords
are written to the Handler
.
- Overrides:
-
setEncoding
in classHandler
- Parameters:
-
encoding
- The name of a supported character encoding. May be null, to indicate the default platform encoding. - Throws:
-
SecurityException
- if a security manager exists and if the caller does not haveLoggingPermission("control")
. -
UnsupportedEncodingException
- if the named encoding is not supported.
publish
public void publish(LogRecord record)
Format and publish a LogRecord
.
The StreamHandler
first checks if there is an OutputStream
and if the given LogRecord
has at least the required log level. If not it silently returns. If so, it calls any associated Filter
to check if the record should be published. If so, it calls its Formatter
to format the record and then writes the result to the current output stream.
If this is the first LogRecord
to be written to a given OutputStream
, the Formatter
's "head" string is written to the stream before the LogRecord
is written.
- Specified by:
-
publish
in classHandler
- Parameters:
-
record
- description of the log event. A null record is silently ignored and is not published
isLoggable
public boolean isLoggable(LogRecord record)
Check if this Handler
would actually log a given LogRecord
.
This method checks if the LogRecord
has an appropriate level and whether it satisfies any Filter
. It will also return false if no output stream has been assigned yet or the LogRecord is null.
- Overrides:
-
isLoggable
in classHandler
- Parameters:
-
record
- aLogRecord
(may be null). - Returns:
- true if the
LogRecord
would be logged.
flush
public void flush()
Flush any buffered messages.
close
public void close() throws SecurityException
Close the current output stream.
The Formatter
's "tail" string is written to the stream before it is closed. In addition, if the Formatter
's "head" string has not yet been written to the stream, it will be written before the "tail" string.
- Specified by:
-
close
in classHandler
- Throws:
-
SecurityException
- if a security manager exists and if the caller does not have LoggingPermission("control").