log4j 连接数据库

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

log4j.properties:
-----------------
### 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中定义的消息  Connected and logged in to

%c   具体的类

%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')

1. 在mysql中创建库logdb
 create database;
2. 在库logdb中创建表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)才会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，这里mysql的driver是mysql-connector-java-3.0.14-production-bin.jar里的com.mysql.jdbc.Driver
   所以，把它放到classpath里, 如在Eclipse测试，需放到project的java build path的Libraries里