Package eu.woolplatform.utils.log

Class Logger

java.lang.Object

eu.woolplatform.utils.log.Logger

public class Logger
extends Object

This class can be used for writing log output. It has a number of static methods to send a log message at a specific level. The supported levels in order from most urgent to least urgent are:

• ASSERT
• ERROR
• WARN
• INFO
• DEBUG
• VERBOSE

The actual behaviour of the logger is determined by the LogDelegate which is set with setLogDelegate(). The default is a DefaultLogDelegate, which writes messages to standard output or standard error. Normally the log delegate should be set and configured once at the start of the application.

Each log method takes a tag parameter. This should be a tag that identifies the source of the log. A log delegate may apply different log levels for different tags. For example one tag may be logged up to the level DEBUG, while another tag is only logged up to the level WARN.

Note that it may require computation time and resources to construct a log message, and this is not necessary if eventually the message is not written because of the log level. To avoid the construction costs, you may check isLoggable() first.

Field Summary

Fields

Modifier and Type	Field	Description
static int	ASSERT
static int	DEBUG
static int	ERROR
static int	INFO
static int	VERBOSE
static int	WARN

Constructor Summary

Constructors

Constructor	Description
Logger()

Method Summary

Modifier and Type	Method	Description
static int	d(String tag, String msg)	Writes a message at level DEBUG.
static int	d(String tag, String msg, Throwable tr)	Writes a message at level DEBUG.
static int	e(String tag, String msg)	Writes a message at level ERROR.
static int	e(String tag, String msg, Throwable tr)	Writes a message at level ERROR.
static LogDelegate	getLogDelegate()	Returns the log delegate.
static String	getStackTraceString(Throwable tr)	Returns the stack trace string for the specified exception.
static int	i(String tag, String msg)	Writes a message at level INFO.
static int	i(String tag, String msg, Throwable tr)	Writes a message at level INFO.
static boolean	isLoggable(String tag, int level)	Determines if messages at the specified level are logged for the specified tag.
static int	println(int priority, String tag, String msg)	Writes a log message.
static void	setLogDelegate(LogDelegate delegate)	Sets the log delegate.
static int	v(String tag, String msg)	Writes a message at level VERBOSE.
static int	v(String tag, String msg, Throwable tr)	Writes a message at level VERBOSE.
static int	w(String tag, String msg)	Writes a message at level WARN.
static int	w(String tag, String msg, Throwable tr)	Writes a message at level WARN.
static int	w(String tag, Throwable tr)	Writes a message at level WARN.
static int	wtf(String tag, String msg)	Writes a message at level ASSERT.
static int	wtf(String tag, String msg, Throwable tr)	Writes a message at level ASSERT.
static int	wtf(String tag, Throwable tr)	Writes a message at level ASSERT.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

VERBOSE

public static final int VERBOSE

See Also:

Constant Field Values

DEBUG

public static final int DEBUG

See Also:

Constant Field Values

INFO

public static final int INFO

See Also:

Constant Field Values

WARN

public static final int WARN

See Also:

Constant Field Values

ERROR

public static final int ERROR

See Also:

Constant Field Values

ASSERT

public static final int ASSERT

See Also:

Constant Field Values

Constructor Detail

Logger

public Logger()

Method Detail

setLogDelegate

public static void setLogDelegate(LogDelegate delegate)

Sets the log delegate. See the top of this page for more information.

Parameters:

delegate - the log delegate

getLogDelegate

public static LogDelegate getLogDelegate()

Returns the log delegate.

Returns:

the log delegate

d

public static int d(String tag,
                    String msg,
                    Throwable tr)

Writes a message at level DEBUG.

Parameters:

tag - the tag

msg - the message

tr - an exception

Returns:

0 if no error occurred, an error code otherwise

d

public static int d(String tag,
                    String msg)

Writes a message at level DEBUG.

Parameters:

tag - the tag

msg - the message

Returns:

0 if no error occurred, an error code otherwise

e

public static int e(String tag,
                    String msg)

Writes a message at level ERROR.

Parameters:

tag - the tag

msg - the message

Returns:

0 if no error occurred, an error code otherwise

e

public static int e(String tag,
                    String msg,
                    Throwable tr)

Writes a message at level ERROR.

Parameters:

tag - the tag

msg - the message

tr - an exception

Returns:

0 if no error occurred, an error code otherwise

getStackTraceString

public static String getStackTraceString(Throwable tr)

Returns the stack trace string for the specified exception. The returned string probably contains new lines, but it does not have a trailing new line.

Parameters:

tr - the exception

Returns:

the stack trace string

i

public static int i(String tag,
                    String msg,
                    Throwable tr)

Writes a message at level INFO.

Parameters:

tag - the tag

msg - the message

tr - an exception

Returns:

0 if no error occurred, an error code otherwise

i

public static int i(String tag,
                    String msg)

Writes a message at level INFO.

Parameters:

tag - the tag

msg - the message

Returns:

0 if no error occurred, an error code otherwise

isLoggable

public static boolean isLoggable(String tag,
                                 int level)

Determines if messages at the specified level are logged for the specified tag.

Parameters:

tag - the tag

level - the level

Returns:

true if the message will be logged, false otherwise

println

public static int println(int priority,
                          String tag,
                          String msg)

Writes a log message.

Parameters:

priority - the log level

tag - the tag

msg - the message

Returns:

0 if no error occurred, an error code otherwise

v

public static int v(String tag,
                    String msg,
                    Throwable tr)

Writes a message at level VERBOSE.

Parameters:

tag - the tag

msg - the message

tr - an exception or null

Returns:

0 if no error occurred, an error code otherwise

v

public static int v(String tag,
                    String msg)

Writes a message at level VERBOSE.

Parameters:

tag - the tag

msg - the message

Returns:

0 if no error occurred, an error code otherwise

w

public static int w(String tag,
                    String msg)

Writes a message at level WARN.

Parameters:

tag - the tag

msg - the message

Returns:

0 if the message was written successfully, an error code otherwise

w

public static int w(String tag,
                    Throwable tr)

Writes a message at level WARN.

Parameters:

tag - the tag

tr - an exception or null

Returns:

0 if no error occurred, an error code otherwise

w

public static int w(String tag,
                    String msg,
                    Throwable tr)

Writes a message at level WARN.

Parameters:

tag - the tag

msg - the message

tr - an exception or null

Returns:

0 if no error occurred, an error code otherwise

wtf

public static int wtf(String tag,
                      String msg)

Writes a message at level ASSERT.

Parameters:

tag - the tag

msg - the message

Returns:

0 if no error occurred, an error code otherwise

wtf

public static int wtf(String tag,
                      Throwable tr)

Writes a message at level ASSERT.

Parameters:

tag - the tag

tr - an exception or null

Returns:

0 if no error occurred, an error code otherwise

wtf

public static int wtf(String tag,
                      String msg,
                      Throwable tr)

Writes a message at level ASSERT.

Parameters:

tag - the tag

msg - the message

tr - an exception or null

Returns:

0 if no error occurred, an error code otherwise