log4j 連接數據庫

表結構：

create table log4j_messages
    (
    log_id serial not null, 
    message varchar(2000),
    classtype varchar(255),
    priority varchar(64),
    log_date timestamp
    );

log4j.properties文件：

### JDBC appender 
log4j.appender.jdbc=org.apache.log4j.jdbc.JDBCAppender 
log4j.appender.jdbc.driver=org.postgresql.Driver 
log4j.appender.jdbc.URL=jdbc:postgresql://localhost:5432/postgres 
log4j.appender.jdbc.user=jiasudu
log4j.appender.jdbc.password=8080
log4j.appender.jdbc.sql=INSERT INTO log4j_messages (message, class, 
priority, log_date) values ('%m', '%c', '%p', to_timestamp('%d', 
'YYYY-MM-DD HH24:MI:SS,MS'))

%m  表示你log中定義的消息  Connected and logged in to 

%c   具體的類
%p   INFO  
to_timestamp('%d',YYYY-MM-DD HH24:MI:SS,MS')   to_timestamp('2009-05-06 15:52:50,156',YYYY-MM-DD HH24:MI:SS,MS')

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1. 在mysql中創建庫logdb
 create database;
2. 在庫logdb中創建表muglog,

 create table muglog{
  id INT(4) UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
    logdate DATE,
  logger VARCHAR(50),
    priority VARCHAR(50),
  message VARCHAR(255)
 };

3. 修改log4j.properties

 ### 限制com.bob.digester(名:dig)纔會log on JDBCAppender ###
 log4j.logger.com.bob.digester=info, dig
 log4j.appender.dig=org.apache.log4j.jdbc.JDBCAppender
 log4j.appender.dig.URL=jdbc:mysql://localhost/logdb
 log4j.appender.dig.driver=com.mysql.jdbc.Driver
 log4j.appender.dig.user=root
 log4j.appender.dig.password=
 log4j.appender.dig.sql=INSERT INTO MUGLOG 
(LOGDATE, LOGGER, PRIORITY, MESSAGE) VALUES ('%d', '%c', '%p', '%m')
 log4j.appender.dig.layout=org.apache.log4j.PatternLayout

4. 注意，這裏mysql的driver是mysql-connector-java-3.0.14-production-bin.jar裏的com.mysql.jdbc.Driver
   所以，把它放到classpath裏, 如在Eclipse測試，需放到project的java build path的Libraries裏