public class

Level

extends Object
implements Serializable
java.lang.Object
   ↳ java.util.logging.Level

Class Overview

The Level class defines a set of standard logging levels that can be used to control logging output. The logging Level objects are ordered and are specified by ordered integers. Enabling logging at a given level also enables logging at all higher levels.

Clients should normally use the predefined Level constants such as Level.SEVERE.

The levels in descending order are:

  • SEVERE (highest value)
  • WARNING
  • INFO
  • CONFIG
  • FINE
  • FINER
  • FINEST (lowest value)
In addition there is a level OFF that can be used to turn off logging, and a level ALL that can be used to enable logging of all messages.

It is possible for third parties to define additional logging levels by subclassing Level. In such cases subclasses should take care to chose unique integer level values and to ensure that they maintain the Object uniqueness property across serialization by defining a suitable readResolve method.

Summary

Fields
public static final Level ALL ALL indicates that all messages should be logged.
public static final Level CONFIG CONFIG is a message level for static configuration messages.
public static final Level FINE FINE is a message level providing tracing information.
public static final Level FINER FINER indicates a fairly detailed tracing message.
public static final Level FINEST FINEST indicates a highly detailed tracing message.
public static final Level INFO INFO is a message level for informational messages.
public static final Level OFF OFF is a special level that can be used to turn off logging.
public static final Level SEVERE SEVERE is a message level indicating a serious failure.
public static final Level WARNING WARNING is a message level indicating a potential problem.
Protected Constructors
Level(String name, int value)
Create a named Level with a given integer value.
Level(String name, int value, String resourceBundleName)
Create a named Level with a given integer value and a given localization resource name.
Public Methods
boolean equals(Object ox)
Compare two objects for value equality.
String getLocalizedName()
Return the localized string name of the Level, for the current default locale.
String getName()
Return the non-localized string name of the Level.
String getResourceBundleName()
Return the level's localization resource bundle name, or null if no localization bundle is defined.
int hashCode()
Generate a hashcode.
final int intValue()
Get the integer value for this level.
synchronized static Level parse(String name)
Parse a level name string into a Level.
final String toString()
Returns a string representation of the object.
[Expand]
Inherited Methods
From class java.lang.Object

Fields

public static final Level ALL

ALL indicates that all messages should be logged. This level is initialized to Integer.MIN_VALUE.

public static final Level CONFIG

CONFIG is a message level for static configuration messages.

CONFIG messages are intended to provide a variety of static configuration information, to assist in debugging problems that may be associated with particular configurations. For example, CONFIG message might include the CPU type, the graphics depth, the GUI look-and-feel, etc. This level is initialized to 700.

public static final Level FINE

FINE is a message level providing tracing information.

All of FINE, FINER, and FINEST are intended for relatively detailed tracing. The exact meaning of the three levels will vary between subsystems, but in general, FINEST should be used for the most voluminous detailed output, FINER for somewhat less detailed output, and FINE for the lowest volume (and most important) messages.

In general the FINE level should be used for information that will be broadly interesting to developers who do not have a specialized interest in the specific subsystem.

FINE messages might include things like minor (recoverable) failures. Issues indicating potential performance problems are also worth logging as FINE. This level is initialized to 500.

public static final Level FINER

FINER indicates a fairly detailed tracing message. By default logging calls for entering, returning, or throwing an exception are traced at this level. This level is initialized to 400.

public static final Level FINEST

FINEST indicates a highly detailed tracing message. This level is initialized to 300.

public static final Level INFO

INFO is a message level for informational messages.

Typically INFO messages will be written to the console or its equivalent. So the INFO level should only be used for reasonably significant messages that will make sense to end users and system admins. This level is initialized to 800.

public static final Level OFF

OFF is a special level that can be used to turn off logging. This level is initialized to Integer.MAX_VALUE.

public static final Level SEVERE

SEVERE is a message level indicating a serious failure.

In general SEVERE messages should describe events that are of considerable importance and which will prevent normal program execution. They should be reasonably intelligible to end users and to system administrators. This level is initialized to 1000.

public static final Level WARNING

WARNING is a message level indicating a potential problem.

In general WARNING messages should describe events that will be of interest to end users or system managers, or which indicate potential problems. This level is initialized to 900.

Protected Constructors

protected Level (String name, int value)

Create a named Level with a given integer value.

Note that this constructor is "protected" to allow subclassing. In general clients of logging should use one of the constant Level objects such as SEVERE or FINEST. However, if clients need to add new logging levels, they may subclass Level and define new constants.

Parameters
name the name of the Level, for example "SEVERE".
value an integer value for the level.
Throws
NullPointerException if the name is null

protected Level (String name, int value, String resourceBundleName)

Create a named Level with a given integer value and a given localization resource name.

Parameters
name the name of the Level, for example "SEVERE".
value an integer value for the level.
resourceBundleName name of a resource bundle to use in localizing the given name. If the resourceBundleName is null or an empty string, it is ignored.
Throws
NullPointerException if the name is null

Public Methods

public boolean equals (Object ox)

Compare two objects for value equality.

Parameters
ox the reference object with which to compare.
Returns
  • true if and only if the two objects have the same level value.

public String getLocalizedName ()

Return the localized string name of the Level, for the current default locale.

If no localization information is available, the non-localized name is returned.

Returns
  • localized name

public String getName ()

Return the non-localized string name of the Level.

Returns
  • non-localized name

public String getResourceBundleName ()

Return the level's localization resource bundle name, or null if no localization bundle is defined.

Returns
  • localization resource bundle name

public int hashCode ()

Generate a hashcode.

Returns
  • a hashcode based on the level value

public final int intValue ()

Get the integer value for this level. This integer value can be used for efficient ordering comparisons between Level objects.

Returns
  • the integer value for this level.

public static synchronized Level parse (String name)

Parse a level name string into a Level.

The argument string may consist of either a level name or an integer value.

For example:

  • "SEVERE"
  • "1000"

Parameters
name string to be parsed
Returns
  • The parsed value. Passing an integer that corresponds to a known name (eg 700) will return the associated name (eg CONFIG). Passing an integer that does not (eg 1) will return a new level name initialized to that value.
Throws
NullPointerException if the name is null
IllegalArgumentException if the value is not valid. Valid values are integers between Integer.MIN_VALUE and Integer.MAX_VALUE, and all known level names. Known names are the levels defined by this class (i.e. FINE, FINER, FINEST), or created by this class with appropriate package access, or new levels defined or created by subclasses.

public final String toString ()

Returns a string representation of the object. In general, the toString method returns a string that "textually represents" this object. The result should be a concise but informative representation that is easy for a person to read. It is recommended that all subclasses override this method.

The toString method for class Object returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@', and the unsigned hexadecimal representation of the hash code of the object. In other words, this method returns a string equal to the value of: 

 getClass().getName() + '@' + Integer.toHexString(hashCode())

Returns
  • the non-localized name of the Level, for example "INFO".