java.util.logging

Class Formatter

public abstract class Formatter extends Object

A Formatter supports handlers by localizing message texts and by subsituting parameter values for their placeholders.

Constructor Summary
protected	Formatter() Constructs a new Formatter.

Method Summary
abstract String	format(LogRecord record) Formats a LogRecord into a string.
String	formatMessage(LogRecord record) Formats the message part of a log record.
String	getHead(Handler handler) Returns a string that handlers are supposed to emit before the first log record.
String	getTail(Handler handler) Returns a string that handlers are supposed to emit after the last log record.

Constructor Detail

Formatter

protected Formatter()

Constructs a new Formatter.

Method Detail

format

public abstract String format(LogRecord record)

Formats a LogRecord into a string. Usually called by handlers which need a string for a log record, for example to append a record to a log file or to transmit a record over the network.

Parameters: record the log record for which a string form is requested.

formatMessage

public String formatMessage(LogRecord record)

Formats the message part of a log record.

First, the Formatter localizes the record message to the default locale by looking up the message in the record's localization resource bundle. If this step fails because there is no resource bundle associated with the record, or because the record message is not a key in the bundle, the raw message is used instead.

Second, the Formatter substitutes appropriate strings for the message parameters. If the record returns a non-empty array for getParameters() and the localized message string contains the character sequence "{0", the formatter uses java.text.MessageFormat to format the message. Otherwise, no parameter substitution is performed.

Parameters: record the log record to be localized and formatted.

Returns: the localized message text where parameters have been substituted by suitable strings.

Throws: NullPointerException if record is null.

getHead

public String getHead(Handler handler)

Returns a string that handlers are supposed to emit before the first log record. The base implementation returns an empty string, but subclasses such as {@link XMLFormatter} override this method in order to provide a suitable header.

Parameters: handler the handler which will prepend the returned string in front of the first log record. This method may inspect certain properties of the handler, for example its encoding, in order to construct the header.

Returns: a string for the header.

getTail

public String getTail(Handler handler)

Returns a string that handlers are supposed to emit after the last log record. The base implementation returns an empty string, but subclasses such as {@link XMLFormatter} override this method in order to provide a suitable tail.

Parameters: handler the handler which will append the returned string after the last log record. This method may inspect certain properties of the handler in order to construct the tail.

Returns: a string for the header.