Package org.springframework.core.log

Class LogMessage

java.lang.Object

org.springframework.core.log.LogMessage

All Implemented Interfaces:

CharSequence

public abstract class LogMessage
extends Object
implements CharSequence

A simple log message type for use with Commons Logging, allowing for convenient lazy resolution of a given Supplier instance (typically bound to a lambda expression) or a printf-style format string (String.format(java.lang.String, java.lang.Object...)) in its toString().

Since:

5.2

Author:

Juergen Hoeller, Sebastien Deleuze

See Also:

• of(Supplier)
• format(String, Object)
• format(String, Object...)
• Log.fatal(Object)
• Log.error(Object)
• Log.warn(Object)
• Log.info(Object)
• Log.debug(Object)
• Log.trace(Object)

Constructor Summary

Constructors

Constructor	Description
LogMessage()

Method Summary

Modifier and Type	Method	Description
char	charAt(int index)
static LogMessage	format(String format, Object arg1)	Build a lazily formatted message from the given format string and argument.
static LogMessage	format(String format, Object... args)	Build a lazily formatted message from the given format string and varargs.
static LogMessage	format(String format, Object arg1, Object arg2)	Build a lazily formatted message from the given format string and arguments.
static LogMessage	format(String format, Object arg1, Object arg2, Object arg3)	Build a lazily formatted message from the given format string and arguments.
static LogMessage	format(String format, Object arg1, Object arg2, Object arg3, Object arg4)	Build a lazily formatted message from the given format string and arguments.
int	length()
static LogMessage	of(Supplier<? extends CharSequence> supplier)	Build a lazily resolving message from the given supplier.
CharSequence	subSequence(int start, int end)
String	toString()	This will be called by the logging provider, potentially once per log target (therefore locally caching the result here).

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.CharSequence

chars, codePoints, isEmpty

Constructor Details

LogMessage

public LogMessage()

Method Details

length

public int length()

Specified by:

length in interface CharSequence

charAt

public char charAt(int index)

Specified by:

charAt in interface CharSequence

subSequence

public CharSequence subSequence(int start,
 int end)

Specified by:

subSequence in interface CharSequence

toString

public String toString()

This will be called by the logging provider, potentially once per log target (therefore locally caching the result here).

Specified by:

toString in interface CharSequence

Overrides:

toString in class Object

of

public static LogMessage of(Supplier<? extends CharSequence> supplier)

Build a lazily resolving message from the given supplier.

Parameters:

supplier - the supplier (typically bound to a lambda expression)

See Also:

• toString()

format

public static LogMessage format(String format,
 @Nullable
 Object arg1)

Build a lazily formatted message from the given format string and argument.

Parameters:

format - the format string (following String.format(java.lang.String, java.lang.Object...) rules)

arg1 - the argument (can be null)

See Also:

• String.format(String, Object...)

format

public static LogMessage format(String format,
 @Nullable
 Object arg1,
 @Nullable
 Object arg2)

Build a lazily formatted message from the given format string and arguments.

Parameters:

format - the format string (following String.format(java.lang.String, java.lang.Object...) rules)

arg1 - the first argument (can be null)

arg2 - the second argument (can be null)

See Also:

• String.format(String, Object...)

format

public static LogMessage format(String format,
 @Nullable
 Object arg1,
 @Nullable
 Object arg2,
 @Nullable
 Object arg3)

Build a lazily formatted message from the given format string and arguments.

Parameters:

format - the format string (following String.format(java.lang.String, java.lang.Object...) rules)

arg1 - the first argument (can be null)

arg2 - the second argument (can be null)

arg3 - the third argument (can be null)

See Also:

• String.format(String, Object...)

format

public static LogMessage format(String format,
 @Nullable
 Object arg1,
 @Nullable
 Object arg2,
 @Nullable
 Object arg3,
 @Nullable
 Object arg4)

Build a lazily formatted message from the given format string and arguments.

Parameters:

format - the format string (following String.format(java.lang.String, java.lang.Object...) rules)

arg1 - the first argument (can be null)

arg2 - the second argument (can be null)

arg3 - the third argument (can be null)

arg4 - the fourth argument (can be null)

See Also:

• String.format(String, Object...)

format

public static LogMessage format(String format,
 @Nullable
 Object... args)

Build a lazily formatted message from the given format string and varargs.

This varargs format() variant may be costly. You should therefore use the individual argument variants whenever possible; format(String, Object), format(String, Object, Object), etc.

Parameters:

format - the format string (following String.format(java.lang.String, java.lang.Object...) rules)

args - the varargs array (can be null and can contain null elements)

See Also:

• String.format(String, Object...)