Apache Log4j API 2.22.0 · org.apache.logging.log4j.Level

Level names with description
Name	Description
`OFF`	No events will be logged.
`FATAL`	A fatal event that will prevent the application from continuing.
`ERROR`	An error in the application, possibly recoverable.
`WARN`	An event that might possible lead to an error.
`INFO`	An event for informational purposes.
`DEBUG`	A general debugging event.
`TRACE`	A fine-grained debug message, typically capturing the flow through the application.
`ALL`	All events should be logged.

Modifier and Type	Field and Description
public static final Level	ALL All events should be logged.
public static final String	CATEGORY Category to be used by custom levels.
public static final Level	DEBUG A general debugging event.
private static final Level[]	EMPTY_ARRAY
public static final Level	ERROR An error in the application, possibly recoverable.
public static final Level	FATAL A fatal event that will prevent the application from continuing.
public static final Level	INFO An event for informational purposes.
private final int	intLevel
private static final ConcurrentMap<String, Level>	LEVELS
private final String	name
public static final Level	OFF No events will be logged.
private static final long	serialVersionUID
private final StandardLevel	standardLevel
public static final Level	TRACE A fine-grained debug message, typically capturing the flow through the application.
public static final Level	WARN An event that might possible lead to an error.

Access	Constructor and Description
private	Level(final String name, final int intLevel)

Method Summary

Modifier and Type	Method and Description
public Level	clone() Overrides java.lang.Object.clone. Creates and returns a copy of this object.
public int	compareTo(final Level the object to be compared. other) Implements java.lang.Comparable.compareTo. Compares this object with the specified object for order.
public boolean	equals(final Object the reference object with which to compare. other) Overrides java.lang.Object.equals. Indicates whether some other object is "equal to" this one.
public static Level	Returns: The Level. forName(final String The name of the level. name, final int The integer value for the Level. If the level was previously created this value is ignored. intValue) Retrieves an existing Level or creates on if it didn't previously exist.
public Class<Level>	getDeclaringClass()
public static Level	Returns: The Level or null. getLevel(final String The name of the Level. name) Return the Level associated with the name or null if the Level cannot be found.
public StandardLevel	Returns: an enum of the standard Levels. getStandardLevel() Gets the standard Level values as an enum.
public int	hashCode() Overrides java.lang.Object.hashCode. Returns a hash code value for this object.
public int	Returns: the value of this Level. intLevel() Gets the integral value of this Level.
public boolean	Returns: True true if this level is in between the given levels isInRange(final Level The minimum level to test. minLevel, final Level The maximum level to test. maxLevel) Compares this level against the levels passed as arguments and returns true if this level is in between the given levels.
public boolean	Returns: True if this level Level is less specific or the same as the given Level. isLessSpecificThan(final Level The level to test. level) Compares this level against the level passed as an argument and returns true if this level is the same or is less specific.
public boolean	Returns: True if this level Level is more specific or the same as the given Level. isMoreSpecificThan(final Level The level to test. level) Compares this level against the level passed as an argument and returns true if this level is the same or is more specific.
public String	Returns: the name of this Level. name() Gets the symbolic name of this Level.
private Object	readResolve()
public static Level	Returns: The Level associated with the String. toLevel(final String The name of the desired Level. level) Converts the string passed as argument to a level.
public static Level	Returns: The Level associated with the String. toLevel(final String The name of the desired Level. name, final Level The Level to use if the String is invalid. defaultLevel) Converts the string passed as argument to a level.
public String	toString() Overrides java.lang.Object.toString. Returns a string representation of the object.
public static Level	Returns: The Level. valueOf(final String The name of the Level to return. name) Return the Level associated with the name.
public static < The enum type whose constant is to be returned T extends Enum<T>> T	Returns: the enum constant of the specified enum type with the specified name valueOf(final Class<T> the `Class` object of the enum type from which to return a constant enumType, final String the name of the constant to return name) Returns the enum constant of the specified enum type with the specified name.
public static Level[]	Returns: An array of Levels. values() Return an array of all the Levels that have been registered.

Inherited from java.lang.Object:: finalize getClass notify notifyAll wait wait wait

ALL	back to summary
public static final Level ALL All events should be logged.

CATEGORY	back to summary
public static final String CATEGORY Category to be used by custom levels. Since 2.1

DEBUG	back to summary
public static final Level DEBUG A general debugging event.

EMPTY_ARRAY	back to summary
private static final Level[] EMPTY_ARRAY

ERROR	back to summary
public static final Level ERROR An error in the application, possibly recoverable.

FATAL	back to summary
public static final Level FATAL A fatal event that will prevent the application from continuing.

INFO	back to summary
public static final Level INFO An event for informational purposes.

intLevel	back to summary
private final int intLevel

LEVELS	back to summary
private static final ConcurrentMap<String, Level> LEVELS

name	back to summary
private final String name

OFF	back to summary
public static final Level OFF No events will be logged.

serialVersionUID	back to summary
private static final long serialVersionUID

standardLevel	back to summary
private final StandardLevel standardLevel

TRACE	back to summary
public static final Level TRACE A fine-grained debug message, typically capturing the flow through the application.

WARN	back to summary
public static final Level WARN An event that might possible lead to an error.

Level	back to summary
private Level(final String name, final int intLevel)

Method Detail

clone back to summary

clone	back to summary
public Level clone() throws CloneNotSupportedException Overrides java.lang.Object.clone. Doc from java.lang.Object.clone. Creates and returns a copy of this object. The precise meaning of "copy" may depend on the class of the object. The general intent is that, for any object `x`, the expression: x.clone() != x will be true, and that the expression: x.clone().getClass() == x.getClass() will be `true`, but these are not absolute requirements. While it is typically the case that: x.clone().equals(x) will be `true`, this is not an absolute requirement. By convention, the returned object should be obtained by calling `super.clone`. If a class and all of its superclasses (except `Object`) obey this convention, it will be the case that `x.clone().getClass() == x.getClass()`. By convention, the object returned by this method should be independent of this object (which is being cloned). To achieve this independence, it may be necessary to modify one or more fields of the object returned by `super.clone` before returning it. Typically, this means copying any mutable objects that comprise the internal "deep structure" of the object being cloned and replacing the references to these objects with references to the copies. If a class contains only primitive fields or references to immutable objects, then it is usually the case that no fields in the object returned by `super.clone` need to be modified. Returns:Level a clone of this instance. Annotations @Override @SuppressWarnings:CloneDoesntCallSuperClone Exceptions CloneNotSupportedException: if the object's class does not support the `Cloneable` interface. Subclasses that override the `clone` method can also throw this exception to indicate that an instance cannot be cloned.

public Level clone() throws CloneNotSupportedException

Overrides java.lang.Object.clone.

Doc from java.lang.Object.clone.

Creates and returns a copy of this object. The precise meaning of "copy" may depend on the class of the object. The general intent is that, for any object x, the expression:

x.clone() != x

will be true, and that the expression:

x.clone().getClass() == x.getClass()

will be true, but these are not absolute requirements. While it is typically the case that:

x.clone().equals(x)

will be true, this is not an absolute requirement.

By convention, the returned object should be obtained by calling super.clone. If a class and all of its superclasses (except Object) obey this convention, it will be the case that x.clone().getClass() == x.getClass().

By convention, the object returned by this method should be independent of this object (which is being cloned). To achieve this independence, it may be necessary to modify one or more fields of the object returned by super.clone before returning it. Typically, this means copying any mutable objects that comprise the internal "deep structure" of the object being cloned and replacing the references to these objects with references to the copies. If a class contains only primitive fields or references to immutable objects, then it is usually the case that no fields in the object returned by super.clone need to be modified.

Returns:Level

a clone of this instance.

Annotations

@Override
@SuppressWarnings:CloneDoesntCallSuperClone

Exceptions

CloneNotSupportedException:: if the object's class does not support the Cloneable interface. Subclasses that override the clone method can also throw this exception to indicate that an instance cannot be cloned.

compareTo back to summary

compareTo	back to summary
public int compareTo(final Level other) Implements java.lang.Comparable.compareTo. Doc from java.lang.Comparable.compareTo. Compares this object with the specified object for order. Returns a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object. The implementor must ensure `signum(x.compareTo(y)) == -signum(y.compareTo(x))` for all `x` and `y`. (This implies that `x.compareTo(y)` must throw an exception if and only if `y.compareTo(x)` throws an exception.) The implementor must also ensure that the relation is transitive: `(x.compareTo(y) > 0 && y.compareTo(z) > 0)` implies `x.compareTo(z) > 0`. Finally, the implementor must ensure that `x.compareTo(y)==0` implies that `signum(x.compareTo(z)) == signum(y.compareTo(z))`, for all `z`. Parameters other:Level the object to be compared. Returns:int a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object. Annotations @Override

public int compareTo(final Level other)

Implements java.lang.Comparable.compareTo.

Doc from java.lang.Comparable.compareTo.

Compares this object with the specified object for order. Returns a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

The implementor must ensure signum(x.compareTo(y)) == -signum(y.compareTo(x)) for all x and y. (This implies that x.compareTo(y) must throw an exception if and only if y.compareTo(x) throws an exception.)

The implementor must also ensure that the relation is transitive: (x.compareTo(y) > 0 && y.compareTo(z) > 0) implies x.compareTo(z) > 0.

Finally, the implementor must ensure that x.compareTo(y)==0 implies that signum(x.compareTo(z)) == signum(y.compareTo(z)), for all z.

Parameters

other:Level: the object to be compared.

Returns:int

a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

Annotations

@Override

equals back to summary

equals	back to summary
public boolean equals(final Object other) Overrides java.lang.Object.equals. Doc from java.lang.Object.equals. Indicates whether some other object is "equal to" this one. The `equals` method implements an equivalence relation on non-null object references: It is reflexive: for any non-null reference value `x`, `x.equals(x)` should return `true`. It is symmetric: for any non-null reference values `x` and `y`, `x.equals(y)` should return `true` if and only if `y.equals(x)` returns `true`. It is transitive: for any non-null reference values `x`, `y`, and `z`, if `x.equals(y)` returns `true` and `y.equals(z)` returns `true`, then `x.equals(z)` should return `true`. It is consistent: for any non-null reference values `x` and `y`, multiple invocations of `x.equals(y)` consistently return `true` or consistently return `false`, provided no information used in `equals` comparisons on the objects is modified. For any non-null reference value `x`, `x.equals(null)` should return `false`. An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes. Parameters other:Object the reference object with which to compare. Returns:boolean `true` if this object is the same as the obj argument; `false` otherwise. Annotations @Override

public boolean equals(final Object other)

Overrides java.lang.Object.equals.

Doc from java.lang.Object.equals.

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

It is reflexive: for any non-null reference value x, x.equals(x) should return true.
It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
For any non-null reference value x, x.equals(null) should return false.

An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.

Parameters

other:Object: the reference object with which to compare.

Returns:boolean

true if this object is the same as the obj argument; false otherwise.

Annotations

@Override

forName	back to summary
public static Level forName(final String name, final int intValue) Retrieves an existing Level or creates on if it didn't previously exist. Parameters name:String The name of the level. intValue:int The integer value for the Level. If the level was previously created this value is ignored. Returns:Level The Level. Exceptions IllegalArgumentException: if the name is null or intValue is less than zero.

forName

back to summary

public static Level forName(final String name, final int intValue)

Retrieves an existing Level or creates on if it didn't previously exist.

Parameters

name:String: The name of the level.
intValue:int: The integer value for the Level. If the level was previously created this value is ignored.

Returns:Level

The Level.

Exceptions

IllegalArgumentException:: if the name is null or intValue is less than zero.

getDeclaringClass	back to summary
public Class<Level> getDeclaringClass()

getLevel	back to summary
public static Level getLevel(final String name) Return the Level associated with the name or null if the Level cannot be found. Parameters name:String The name of the Level. Returns:Level The Level or null. Exceptions IllegalArgumentException: if the name is null.

getLevel

back to summary

public static Level getLevel(final String name)

Return the Level associated with the name or null if the Level cannot be found.

Parameters

name:String: The name of the Level.

Returns:Level

The Level or null.

Exceptions

IllegalArgumentException:: if the name is null.

getStandardLevel	back to summary
public StandardLevel getStandardLevel() Gets the standard Level values as an enum. Returns:StandardLevel an enum of the standard Levels.

getStandardLevel

back to summary

public StandardLevel getStandardLevel()

Gets the standard Level values as an enum.

Returns:StandardLevel: an enum of the standard Levels.

hashCode back to summary

hashCode	back to summary
public int hashCode() Overrides java.lang.Object.hashCode. Doc from java.lang.Object.hashCode. Returns a hash code value for this object. This method is supported for the benefit of hash tables such as those provided by `java.util.HashMap`. The general contract of `hashCode` is: Whenever it is invoked on the same object more than once during an execution of a Java application, the `hashCode` method must consistently return the same integer, provided no information used in `equals` comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application. If two objects are equal according to the `equals` method, then calling the `hashCode` method on each of the two objects must produce the same integer result. It is not required that if two objects are unequal according to the `equals` method, then calling the `hashCode` method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables. Returns:int a hash code value for this object Annotations @Override

public int hashCode()

Overrides java.lang.Object.hashCode.

Doc from java.lang.Object.hashCode.

Returns a hash code value for this object. This method is supported for the benefit of hash tables such as those provided by java.util.HashMap.

The general contract of hashCode is:

Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
If two objects are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result.
It is not required that if two objects are unequal according to the equals method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.

Returns:int

a hash code value for this object

Annotations

@Override

intLevel	back to summary
public int intLevel() Gets the integral value of this Level. Returns:int the value of this Level.

intLevel

back to summary

public int intLevel()

Gets the integral value of this Level.

Returns:int: the value of this Level.

isInRange	back to summary
public boolean isInRange(final Level minLevel, final Level maxLevel) Compares this level against the levels passed as arguments and returns true if this level is in between the given levels. Parameters minLevel:Level The minimum level to test. maxLevel:Level The maximum level to test. Returns:boolean True true if this level is in between the given levels Since 2.4

isInRange

back to summary

public boolean isInRange(final Level minLevel, final Level maxLevel)

Compares this level against the levels passed as arguments and returns true if this level is in between the given levels.

Parameters

minLevel:Level: The minimum level to test.
maxLevel:Level: The maximum level to test.

Returns:boolean

True true if this level is in between the given levels

Since

2.4

isLessSpecificThan back to summary

isLessSpecificThan	back to summary
public boolean isLessSpecificThan(final Level level) Compares this level against the level passed as an argument and returns true if this level is the same or is less specific. Concretely, `ALL` is less specific than `TRACE`, which is less specific than `DEBUG`, which is less specific than `INFO`, which is less specific than `WARN`, which is less specific than `ERROR`, which is less specific than `FATAL`, and finally `OFF`, which is the most specific standard level. Parameters level:Level The level to test. Returns:boolean True if this level Level is less specific or the same as the given Level.

public boolean isLessSpecificThan(final Level level)

Compares this level against the level passed as an argument and returns true if this level is the same or is less specific.

Concretely, ALL is less specific than TRACE, which is less specific than DEBUG, which is less specific than INFO, which is less specific than WARN, which is less specific than ERROR, which is less specific than FATAL, and finally OFF, which is the most specific standard level.

Parameters

level:Level: The level to test.

Returns:boolean

True if this level Level is less specific or the same as the given Level.

isMoreSpecificThan back to summary

isMoreSpecificThan	back to summary
public boolean isMoreSpecificThan(final Level level) Compares this level against the level passed as an argument and returns true if this level is the same or is more specific. Concretely, `FATAL` is more specific than `ERROR`, which is more specific than `WARN`, etc., until `TRACE`, and finally `ALL`, which is the least specific standard level. The most specific level is `OFF`. Parameters level:Level The level to test. Returns:boolean True if this level Level is more specific or the same as the given Level.

public boolean isMoreSpecificThan(final Level level)

Compares this level against the level passed as an argument and returns true if this level is the same or is more specific.

Concretely, FATAL is more specific than ERROR, which is more specific than WARN, etc., until TRACE, and finally ALL, which is the least specific standard level. The most specific level is OFF.

Parameters

level:Level: The level to test.

Returns:boolean

True if this level Level is more specific or the same as the given Level.

name back to summary

name	back to summary
public String name() Gets the symbolic name of this Level. Equivalent to calling `toString()`. Returns:String the name of this Level.

public String name()

Gets the symbolic name of this Level. Equivalent to calling toString().

Returns:String: the name of this Level.

readResolve	back to summary
private Object readResolve()

toLevel back to summary

toLevel	back to summary
public static Level toLevel(final String level) Converts the string passed as argument to a level. If the conversion fails, then this method returns `DEBUG`. Parameters level:String The name of the desired Level. Returns:Level The Level associated with the String.

public static Level toLevel(final String level)

Converts the string passed as argument to a level. If the conversion fails, then this method returns DEBUG.

Parameters

level:String: The name of the desired Level.

Returns:Level

The Level associated with the String.

toLevel back to summary

toLevel	back to summary
public static Level toLevel(final String name, final Level defaultLevel) Converts the string passed as argument to a level. If the conversion fails, then this method returns the value of `defaultLevel`. Parameters name:String The name of the desired Level. defaultLevel:Level The Level to use if the String is invalid. Returns:Level The Level associated with the String.

public static Level toLevel(final String name, final Level defaultLevel)

Converts the string passed as argument to a level. If the conversion fails, then this method returns the value of defaultLevel.

Parameters

name:String: The name of the desired Level.
defaultLevel:Level: The Level to use if the String is invalid.

Returns:Level

The Level associated with the String.

toString back to summary

toString	back to summary
public String toString() Overrides java.lang.Object.toString. Doc from java.lang.Object.toString. Returns a string representation of the object. Satisfying this method's contract implies a non-`null` result must be returned. Returns:String a string representation of the object Annotations @Override

public String toString()

Overrides java.lang.Object.toString.

Doc from java.lang.Object.toString.

Returns a string representation of the object. Satisfying this method's contract implies a non-null result must be returned.

Returns:String

a string representation of the object

Annotations

@Override

valueOf back to summary

valueOf	back to summary
public static Level valueOf(final String name) Return the Level associated with the name. Parameters name:String The name of the Level to return. Returns:Level The Level. Exceptions NullPointerException: if the Level name is `null`. IllegalArgumentException: if the Level name is not registered.

public static Level valueOf(final String name)

Return the Level associated with the name.

Parameters

name:String: The name of the Level to return.

Returns:Level

The Level.

Exceptions

NullPointerException:: if the Level name is null.
IllegalArgumentException:: if the Level name is not registered.

valueOf back to summary

valueOf	back to summary
public static <T extends Enum<T>> T valueOf(final Class<T> enumType, final String name) Returns the enum constant of the specified enum type with the specified name. The name must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.) Parameters <T> The enum type whose constant is to be returned enumType:Class<T> the `Class` object of the enum type from which to return a constant name:String the name of the constant to return Returns:T the enum constant of the specified enum type with the specified name Exceptions IllegalArgumentException: if the specified enum type has no constant with the specified name, or the specified class object does not represent an enum type NullPointerException: if `enumType` or `name` are `null` See Also `java.lang.Enum#valueOf(Class, String)`

public static <T extends Enum<T>> T valueOf(final Class<T> enumType, final String name)

Returns the enum constant of the specified enum type with the specified name. The name must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters

<T>: The enum type whose constant is to be returned
enumType:Class<T>: the Class object of the enum type from which to return a constant
name:String: the name of the constant to return

Returns:T

the enum constant of the specified enum type with the specified name

Exceptions

IllegalArgumentException:: if the specified enum type has no constant with the specified name, or the specified class object does not represent an enum type
NullPointerException:: if enumType or name are null

See Also

java.lang.Enum#valueOf(Class, String)

values	back to summary
public static Level[] values() Return an array of all the Levels that have been registered. Returns:Level[] An array of Levels.

values

back to summary

public static Level[] values()

Return an array of all the Levels that have been registered.

Returns:Level[]: An array of Levels.

public final Class Level

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail