org.apache.poi.util

Class NullLogger

java.lang.Object

org.apache.poi.util.NullLogger

All Implemented Interfaces:

POILogger

@Internal
public class NullLogger
extends java.lang.Object
implements POILogger

An empty-implementation of the POILogger. This can be used to not log anything, however the suggested approach in production systems is to use the CommonsLogger and configure proper log-handling via Apache Commons Logging. (POILogger 的空实现。这可用于不记录任何内容，但是在生产系统中建议的方法是使用 CommonsLogger 并通过 Apache Commons Logging 配置正确的日志处理。)

Field Summary

Fields inherited from interface org.apache.poi.util.POILogger

DEBUG, ERROR, FATAL, INFO, WARN

Constructor Summary

Constructors

Constructor and Description
NullLogger()

Method Summary

Modifier and Type	Method and Description
void	_log(int level, java.lang.Object obj1) Log a message (记录消息)
void	_log(int level, java.lang.Object obj1, java.lang.Throwable exception) Log a message (记录消息)
boolean	check(int level) Check if a logger is enabled to log at the specified level (检查是否启用了记录器以在指定级别进行记录)
void	initialize(java.lang.String cat) Initialize the Logger - belongs to the SPI, called from the POILogFactory (初始化 Logger - 属于 SPI，从 POILogFactory 调用)
void	log(int level, java.lang.Object... objs) Log a message. (记录一条消息。)

Methods inherited from class java.lang.Object

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

Constructor Detail

NullLogger

public NullLogger()

Method Detail

initialize

public void initialize(java.lang.String cat)

Description copied from interface: POILogger

Initialize the Logger - belongs to the SPI, called from the POILogFactory (初始化 Logger - 属于 SPI，从 POILogFactory 调用)

Specified by:

initialize in interface POILogger (在接口 POILogger 中初始化)

Parameters:

cat - the String that defines the log (cat - 定义日志的字符串)

_log

public void _log(int level,
                 java.lang.Object obj1)

Log a message (记录消息)

Specified by:

_log in interface POILogger (_log 接口 POILogger)

Parameters:

level - One of DEBUG, INFO, WARN, ERROR, FATAL (level - DEBUG、INFO、WARN、ERROR、FATAL 之一)

obj1 - The object to log. (obj1 - 要记录的对象。)

_log

public void _log(int level,
                 java.lang.Object obj1,
                 java.lang.Throwable exception)

Log a message (记录消息)

Specified by:

_log in interface POILogger (_log 接口 POILogger)

Parameters:

level - One of DEBUG, INFO, WARN, ERROR, FATAL (level - DEBUG、INFO、WARN、ERROR、FATAL 之一)

obj1 - The object to log. This is converted to a string. (obj1 - 要记录的对象。这将转换为字符串。)

exception - An exception to be logged (exception - 要记录的异常)

log

public void log(int level,
                java.lang.Object... objs)

Log a message. Lazily appends Object parameters together. If the last parameter is a Throwable it is logged specially. (记录一条消息。懒惰地将对象参数附加在一起。如果最后一个参数是 Throwable，则专门记录它。)

Specified by:

log in interface POILogger (登录界面POILogger)

Parameters:

level - One of DEBUG, INFO, WARN, ERROR, FATAL (level - DEBUG、INFO、WARN、ERROR、FATAL 之一)

objs - the objects to place in the message (objs - 放置在消息中的对象)

check

public boolean check(int level)

Check if a logger is enabled to log at the specified level (检查是否启用了记录器以在指定级别进行记录)

Specified by:

check in interface POILogger (签入界面POILogger)

Parameters:

level - One of DEBUG, INFO, WARN, ERROR, FATAL (level - DEBUG、INFO、WARN、ERROR、FATAL 之一)