TreeLogger (Google Web Toolkit Javadoc)

java.lang.Object
- com.google.gwt.core.ext.TreeLogger

```
public abstract class TreeLogger
extends java.lang.Object
```
An interface used to log messages in deferred binding generators.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`TreeLogger.HelpInfo` Provides extra information to the user, generally details of what caused the problem or what the user should do to fix the problem.
`static class`	`TreeLogger.Type` A type-safe enum of all possible logging severity types.

Field Summary

Fields
Modifier and Type	Field and Description
`static TreeLogger.Type`	`ALL` Logs everything -- quite a bit of stuff.
`static TreeLogger.Type`	`DEBUG` Logs detailed information that could be useful during debugging.
`static TreeLogger.Type`	`ERROR` Logs an error.
`static TreeLogger.Type`	`INFO` Logs information.
`static TreeLogger`	`NULL` A valid logger that ignores all messages.
`static TreeLogger.Type`	`SPAM` Logs extremely verbose and detailed information that is typically useful only to product implementors.
`static TreeLogger.Type`	`TRACE` Logs information related to lower-level operation.
`static TreeLogger.Type`	`WARN` Logs a warning.

Constructor Summary

Constructors
Constructor and Description

TreeLogger()

Constructors
Constructor and Description
`TreeLogger()`

Method Summary

Methods
Modifier and Type	Method and Description
`TreeLogger`	`branch(TreeLogger.Type type, java.lang.String msg)` Calls `branch(com.google.gwt.core.ext.TreeLogger.Type, String, Throwable, com.google.gwt.core.ext.TreeLogger.HelpInfo)` with a `null` `caught` and `helpInfo`.
`TreeLogger`	`branch(TreeLogger.Type type, java.lang.String msg, java.lang.Throwable caught)` Calls `branch(com.google.gwt.core.ext.TreeLogger.Type, String, Throwable, com.google.gwt.core.ext.TreeLogger.HelpInfo)` with a `null` `helpInfo`.
`abstract TreeLogger`	`branch(TreeLogger.Type type, java.lang.String msg, java.lang.Throwable caught, TreeLogger.HelpInfo helpInfo)` Produces a branched logger, which can be used to write messages that are logically grouped together underneath the current logger.
`abstract boolean`	`isLoggable(TreeLogger.Type type)` Determines whether or not a log entry of the specified type would actually be logged.
`void`	`log(TreeLogger.Type type, java.lang.String msg)` Calls `log(TreeLogger.Type, String, Throwable, HelpInfo)` with a `null` `caught` and `helpInfo`.
`void`	`log(TreeLogger.Type type, java.lang.String msg, java.lang.Throwable caught)` Calls `log(TreeLogger.Type, String, Throwable, HelpInfo)` with a `null` `helpInfo`.
`abstract void`	`log(TreeLogger.Type type, java.lang.String msg, java.lang.Throwable caught, TreeLogger.HelpInfo helpInfo)` Logs a message and/or an exception, with optional help info.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - ERROR
```
public static final TreeLogger.Type ERROR
```
    Logs an error.
  - WARN
```
public static final TreeLogger.Type WARN
```
    Logs a warning.
  - INFO
```
public static final TreeLogger.Type INFO
```
    Logs information.
  - TRACE
```
public static final TreeLogger.Type TRACE
```
    Logs information related to lower-level operation.
  - DEBUG
```
public static final TreeLogger.Type DEBUG
```
    Logs detailed information that could be useful during debugging.
  - SPAM
```
public static final TreeLogger.Type SPAM
```
    Logs extremely verbose and detailed information that is typically useful only to product implementors.
  - ALL
```
public static final TreeLogger.Type ALL
```
    Logs everything -- quite a bit of stuff.
  - NULL
```
public static final TreeLogger NULL
```
    A valid logger that ignores all messages. Occasionally useful when calling methods that require a logger parameter.
- Constructor Detail
  - TreeLogger
```
public TreeLogger()
```
- Method Detail
  - branch
```
public final TreeLogger branch(TreeLogger.Type type,
                java.lang.String msg)
```
    Calls branch(com.google.gwt.core.ext.TreeLogger.Type, String, Throwable, com.google.gwt.core.ext.TreeLogger.HelpInfo) with a null caught and helpInfo.
  - branch
```
public final TreeLogger branch(TreeLogger.Type type,
                java.lang.String msg,
                java.lang.Throwable caught)
```
    Calls branch(com.google.gwt.core.ext.TreeLogger.Type, String, Throwable, com.google.gwt.core.ext.TreeLogger.HelpInfo) with a null helpInfo.
  - branch
```
public abstract TreeLogger branch(TreeLogger.Type type,
                java.lang.String msg,
                java.lang.Throwable caught,
                TreeLogger.HelpInfo helpInfo)
```
    Produces a branched logger, which can be used to write messages that are logically grouped together underneath the current logger. The details of how/if the resulting messages are displayed is implementation-dependent.
    The log message supplied when branching serves two purposes. First, the message should be considered a heading for all the child messages below it. Second, the type of the message provides a hint as to the importance of the children below it. As an optimization, an implementation could return a "no-op" logger if messages of the specified type weren't being logged, which the implication being that all nested log messages were no more important than the level of their branch parent.
    
    As an example of how hierarchical logging can be used, a branched logger in a GUI could write log message as child items of a parent node in a tree control. If logging to streams, such as a text console, the branched logger could prefix each entry with a unique string and indent its text so that it could be sorted later to reconstruct a proper hierarchy.
    
    Parameters:
    type -
    msg - an optional message to log, which can be null if only an exception is being logged
    caught - an optional exception to log, which can be null if only a message is being logged
    helpInfo - extra information that might be used by the logger to provide extended information to the user
    
    Returns:
    an instance of TreeLogger representing the new branch of the log; may be the same instance on which this method is called
  - isLoggable
```
public abstract boolean isLoggable(TreeLogger.Type type)
```
    Determines whether or not a log entry of the specified type would actually be logged. Caller use this method to avoid constructing log messages that would be thrown away.
  - log
```
public final void log(TreeLogger.Type type,
       java.lang.String msg)
```
    Calls log(TreeLogger.Type, String, Throwable, HelpInfo) with a null caught and helpInfo.
  - log
```
public final void log(TreeLogger.Type type,
       java.lang.String msg,
       java.lang.Throwable caught)
```
    Calls log(TreeLogger.Type, String, Throwable, HelpInfo) with a null helpInfo.
  - log
```
public abstract void log(TreeLogger.Type type,
       java.lang.String msg,
       java.lang.Throwable caught,
       TreeLogger.HelpInfo helpInfo)
```
    Logs a message and/or an exception, with optional help info. It is also legal to call this method using null arguments for both msg and caught, in which case the log event can be ignored. The info can provide extra information to the logger; a logger may choose to ignore this info.
    
    Parameters:
    type -
    msg - an optional message to log, which can be null if only an exception is being logged
    caught - an optional exception to log, which can be null if only a message is being logged
    helpInfo - extra information that might be used by the logger to provide extended information to the user

Class TreeLogger

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

ERROR

WARN

INFO

TRACE

DEBUG

SPAM

ALL

NULL

Constructor Detail

TreeLogger

Method Detail

branch

branch

branch

isLoggable

log

log

log