最近被問到一個log4j分不同文件記錄不同級別日志的問題，一下給難倒了，以前沒有留意過log4j的具體功能，只是了解了下。如今自己還差的遠(yuǎn)啊。╮(╯▽╰)╭。。。

參考了前段時間的那個項目中的log4j配置文件，發(fā)現(xiàn)那個只不過將不同模組的日志記錄到不同的日志文件。并未按日志級別分文件記錄。自己在動手調(diào)試的過程中結(jié)合查閱網(wǎng)上很多博文，終于以xml格式配置的方式調(diào)通。具體配置如下：

Xml代碼

1. <?xml version="1.0" encoding="UTF-8"?>  
2. <!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">  
3. <log4j:configuration xmlns:log4j='http://jakarta./log4j/'>  
4.        
5.     <appender name="stdout" class="org.apache.log4j.ConsoleAppender">  
6.         <layout class="org.apache.log4j.PatternLayout">  
7.             <param name="ConversionPattern"  
8.                 value="%d{yyyy/MM/dd HH:mm:ss.sss} [%-5p] %c - %m%n"/>  
9.         </layout>  
10.     </appender>  
11.        
12.     <appender name="traceLog4Debug" class="org.apache.log4j.RollingFileAppender">  
13.         <param name="File" value="C:/traceLog4Debug.log"/>  
14.         <param name="maxFileSize" value="2000KB"/>  
15.         <param name="maxBackupIndex" value="20"/>  
16.         <layout class="org.apache.log4j.PatternLayout">  
17.             <param name="ConversionPattern"  
18.                 value="%d{yyyy/MM/dd HH:mm:ss.sss} [%-5p] %c - %m%n"/>  
19.         </layout>  
20.     </appender>  
21.        
22.     <appender name="debugLog" class="org.apache.log4j.RollingFileAppender">  
23.         <param name="File" value="C:/debug.log"/>  
24.         <param name="maxFileSize" value="2000KB"/>  
25.         <param name="maxBackupIndex" value="10"/>  
26.         <layout class="org.apache.log4j.PatternLayout">  
27.             <param name="ConversionPattern"  
28.                 value="%d{yyyy/MM/dd HH:mm:ss.sss} [%-5p] %c - %m%n"/>  
29.         </layout>  
30.         <SPAN style="COLOR: #ff0000"><!-- filter作用？  配置LevelMax與LevelMin限定輸出到文件的日志級別 -->  
31.         <filter class="org.apache.log4j.varia.LevelRangeFilter">  
32.                         <param name="LevelMax" value="DEBUG" />  
33.                         <param name="LevelMin" value="DEBUG" />  
34.                 </filter></SPAN>  
35.     </appender>  
36.        
37.     <appender name="infoLog" class="org.apache.log4j.RollingFileAppender">  
38.         <param name="File" value="C:/info.log"/>  
39.         <param name="maxFileSize" value="2000KB"/>  
40.         <param name="maxBackupIndex" value="10"/>  
41.         <layout class="org.apache.log4j.PatternLayout">  
42.             <param name="ConversionPattern"  
43.                 value="%d{yyyy/MM/dd HH:mm:ss.sss} [%-5p] %c - %m%n"/>  
44.         </layout>  
45.         <filter class="org.apache.log4j.varia.LevelRangeFilter">  
46.                     <param name="LevelMax" value="INFO" />  
47.                     <param name="LevelMin" value="INFO" />  
48.             </filter>  
49.     </appender>  
50.        
51.     <appender name="warnLog" class="org.apache.log4j.RollingFileAppender">  
52.         <param name="File" value="C:/warn.log"/>  
53.         <param name="maxFileSize" value="2000KB"/>  
54.         <param name="maxBackupIndex" value="10"/>  
55.         <layout class="org.apache.log4j.PatternLayout">  
56.             <param name="ConversionPattern"  
57.                 value="%d{yyyy/MM/dd HH:mm:ss.sss} [%-5p] %c - %m%n"/>  
58.         </layout>  
59.         <filter class="org.apache.log4j.varia.LevelRangeFilter">  
60.                     <param name="LevelMax" value="WARN" />  
61.                     <param name="LevelMin" value="WARN" />  
62.             </filter>  
63.     </appender>  
64.        
65.     <appender name="errorLog" class="org.apache.log4j.RollingFileAppender">  
66.         <param name="File" value="C:/error.log"/>  
67.         <param name="maxFileSize" value="2000KB"/>  
68.         <param name="maxBackupIndex" value="10"/>  
69.         <layout class="org.apache.log4j.PatternLayout">  
70.             <param name="ConversionPattern"  
71.                 value="%d{yyyy/MM/dd HH:mm:ss.sss} [%-5p] %c - %m%n"/>  
72.         </layout>  
73.         <filter class="org.apache.log4j.varia.LevelRangeFilter">  
74.                     <param name="LevelMax" value="ERROR" />  
75.                     <param name="LevelMin" value="ERROR" />  
76.             </filter>  
77.     </appender>  
78.        
79.     <!-- 記錄該包下所有日志 -->  
80.     <logger name="com.javaeye.paopaohou">  
81.         <level value="ALL"/>  
82.         <appender-ref ref="stdout"/>  
83.         <appender-ref ref="traceLog4Debug"/>  
84.         <appender-ref ref="debugLog"/>  
85.         <appender-ref ref="infoLog"/>  
86.         <appender-ref ref="warnLog"/>  
87.         <appender-ref ref="errorLog"/>  
88.     </logger>  
89.        
90.        
91.        
92.     <logger name="org.hibernate.SQL">  
93.         <level value="DEBUG"/>  
94.         <appender-ref ref="traceLog4Debug"/>  
95.         <appender-ref ref="stdout"/>  
96.     </logger>  
97.        
98.     <logger name="org.hibernate">  
99.         <level value="error"/>  
100.         <appender-ref ref="traceLog4Debug"/>  
101.         <appender-ref ref="stdout"/>  
102.     </logger>  
103.        
104.     <logger name="org.springframework">  
105.         <level value="error"/>  
106.         <appender-ref ref="traceLog4Debug"/>  
107.         <appender-ref ref="stdout"/>  
108.     </logger>  
109.   
110.        
111. </log4j:configuration>  

<?xml version="1.0" encoding="UTF-8"?>
            <!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
            <log4j:configuration xmlns:log4j='http://jakarta./log4j/'>
            <appender name="stdout" class="org.apache.log4j.ConsoleAppender">
            <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern"
            value="%d{yyyy/MM/dd HH:mm:ss.sss} [%-5p] %c - %m%n"/>
            </layout>
            </appender>
            <appender name="traceLog4Debug" class="org.apache.log4j.RollingFileAppender">
            <param name="File" value="C:/traceLog4Debug.log"/>
            <param name="maxFileSize" value="2000KB"/>
            <param name="maxBackupIndex" value="20"/>
            <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern"
            value="%d{yyyy/MM/dd HH:mm:ss.sss} [%-5p] %c - %m%n"/>
            </layout>
            </appender>
            <appender name="debugLog" class="org.apache.log4j.RollingFileAppender">
            <param name="File" value="C:/debug.log"/>
            <param name="maxFileSize" value="2000KB"/>
            <param name="maxBackupIndex" value="10"/>
            <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern"
            value="%d{yyyy/MM/dd HH:mm:ss.sss} [%-5p] %c - %m%n"/>
            </layout>
            <!-- filter作用？  配置LevelMax與LevelMin限定輸出到文件的日志級別 -->
            <filter class="org.apache.log4j.varia.LevelRangeFilter">
            <param name="LevelMax" value="DEBUG" />
            <param name="LevelMin" value="DEBUG" />
            </filter>
            </appender>
            <appender name="infoLog" class="org.apache.log4j.RollingFileAppender">
            <param name="File" value="C:/info.log"/>
            <param name="maxFileSize" value="2000KB"/>
            <param name="maxBackupIndex" value="10"/>
            <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern"
            value="%d{yyyy/MM/dd HH:mm:ss.sss} [%-5p] %c - %m%n"/>
            </layout>
            <filter class="org.apache.log4j.varia.LevelRangeFilter">
            <param name="LevelMax" value="INFO" />
            <param name="LevelMin" value="INFO" />
            </filter>
            </appender>
            <appender name="warnLog" class="org.apache.log4j.RollingFileAppender">
            <param name="File" value="C:/warn.log"/>
            <param name="maxFileSize" value="2000KB"/>
            <param name="maxBackupIndex" value="10"/>
            <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern"
            value="%d{yyyy/MM/dd HH:mm:ss.sss} [%-5p] %c - %m%n"/>
            </layout>
            <filter class="org.apache.log4j.varia.LevelRangeFilter">
            <param name="LevelMax" value="WARN" />
            <param name="LevelMin" value="WARN" />
            </filter>
            </appender>
            <appender name="errorLog" class="org.apache.log4j.RollingFileAppender">
            <param name="File" value="C:/error.log"/>
            <param name="maxFileSize" value="2000KB"/>
            <param name="maxBackupIndex" value="10"/>
            <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern"
            value="%d{yyyy/MM/dd HH:mm:ss.sss} [%-5p] %c - %m%n"/>
            </layout>
            <filter class="org.apache.log4j.varia.LevelRangeFilter">
            <param name="LevelMax" value="ERROR" />
            <param name="LevelMin" value="ERROR" />
            </filter>
            </appender>
            <!-- 記錄該包下所有日志 -->
            <logger name="com.javaeye.paopaohou">
            <level value="ALL"/>
            <appender-ref ref="stdout"/>
            <appender-ref ref="traceLog4Debug"/>
            <appender-ref ref="debugLog"/>
            <appender-ref ref="infoLog"/>
            <appender-ref ref="warnLog"/>
            <appender-ref ref="errorLog"/>
            </logger>
            <logger name="org.hibernate.SQL">
            <level value="DEBUG"/>
            <appender-ref ref="traceLog4Debug"/>
            <appender-ref ref="stdout"/>
            </logger>
            <logger name="org.hibernate">
            <level value="error"/>
            <appender-ref ref="traceLog4Debug"/>
            <appender-ref ref="stdout"/>
            </logger>
            <logger name="org.springframework">
            <level value="error"/>
            <appender-ref ref="traceLog4Debug"/>
            <appender-ref ref="stdout"/>
            </logger>
            </log4j:configuration>

 只不過是在配置appender的時候配置了一個LevelRangeFilter的filter，并配置LevelMax與LevelMin(最大最小級別)，加個測試類：

Java代碼

1. package com.javaeye.paopaohou;   
2.   
3. import org.apache.log4j.Logger;   
4.   
5. public class TestLog4j {   
6.   
7.     private static final Logger log = Logger.getLogger(TestLog4j.class);   
8.     /**  
9.      * 測試log4j不同級別日志分文件記錄  
10.      *  
11.      */  
12.   
13.     public static void main(String[] args) {   
14.         log.debug("debug...");   
15.         log.info("info...");   
16.         log.warn("warn...");   
17.         log.error("error...");   
18.   
19.     }   
20.   
21. }  

package com.javaeye.paopaohou;
            import org.apache.log4j.Logger;
            public class TestLog4j {
            private static final Logger log = Logger.getLogger(TestLog4j.class);
            /**
            * 測試log4j不同級別日志分文件記錄
            *
            */
            public static void main(String[] args) {
            log.debug("debug...");
            log.info("info...");
            log.warn("warn...");
            log.error("error...");
            }
            }

 這樣就可以將不同級別的日志記錄到不同的文件，可惜使用properties格式的log4j配置文件卻沒有調(diào)通。是因為properties格式的文件不支持這么配置嗎？不知道哪位在使用properties文件時候這么做過，還有我發(fā)現(xiàn)我經(jīng)歷的項目都使用xml格式的配置文件好像多于properties格式的文件，是因為xml格式配置起來更靈活嗎？學(xué)習(xí)。