Class StreamHandler
- Direct Known Subclasses:
ConsoleHandler
,FileHandler
,SocketHandler
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
ConstructorDescriptionCreate aStreamHandler
, with no current output stream.StreamHandler
(OutputStream out, Formatter formatter) Create aStreamHandler
with a givenFormatter
and output stream. -
Method Summary
Modifier and TypeMethodDescriptionvoid
close()
Close the current output stream.void
flush()
Flush any buffered messages.boolean
isLoggable
(LogRecord record) Check if thisHandler
would actually log a givenLogRecord
.void
Format and publish aLogRecord
.void
setEncoding
(String encoding) Set (or change) the character encoding used by thisHandler
.protected void
Change the output stream.Methods declared in class java.util.logging.Handler
getEncoding, getErrorManager, getFilter, getFormatter, getLevel, reportError, setErrorManager, setFilter, setFormatter, setLevel
-
Constructor Details
-
StreamHandler
public StreamHandler()Create aStreamHandler
, with no current output stream. -
StreamHandler
Create aStreamHandler
with a givenFormatter
and output stream.- Parameters:
out
- the target output streamformatter
- Formatter to be used to format output
-
-
Method Details
-
setOutputStream
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
Set (or change) the character encoding used by thisHandler
.The encoding should be set before any
LogRecords
are written to theHandler
.- 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
Format and publish aLogRecord
.The
StreamHandler
first checks if there is anOutputStream
and if the givenLogRecord
has at least the required log level. If not it silently returns. If so, it calls any associatedFilter
to check if the record should be published. If so, it calls itsFormatter
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 givenOutputStream
, theFormatter
's "head" string is written to the stream before theLogRecord
is written. -
isLoggable
Check if thisHandler
would actually log a givenLogRecord
.This method checks if the
LogRecord
has an appropriate level and whether it satisfies anyFilter
. 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
-
close
Close the current output stream.The
Formatter
's "tail" string is written to the stream before it is closed. In addition, if theFormatter
'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").
-