log4j 怎么按时间和大小进行分割

[sinat_29891073]

项目本来是按日志进行分割，但是后续每天产生的日志太多，打开都很不方便，怎么在按日期分割的基础上再按大小进行分割呢？出了自己写个RollingFileAppender类还有没有其他办法？

[打不打伞心都是湿的-_-]

，dom4j在日志分类上面做的很好。但要涉及到灵活修改该文件的时候就。。。。对于这个问题，实在是让人头大，， 我的项目遇到需要同时使用多个log4j配置文件的问题，，，类似你的问题，弄了大半月最后还是，自己动手写了个Log4JInit类，在应用启动的时候创建log4j.xml。 哥们你别找答案了没有的。。

[打不打伞心都是湿的-_-]

写一个log4jInit吧，，在你的log4j里面设置几个变量，例如${some_day_path},然后使用apache有个项目叫configuration来替换你的变量。 看看我的，对你有帮助否：

/**
* @Synopsis  读取多个log4j配置文件合并成一个。main-log4j.xml为主配置文件。只有主配置文件中的root与root appender
* 才生效。
*/
public class LoggingInit{
    private static final String CONFIG_FILE_NAME_PATTERN = "^(?!log4j)[a-zA-Z0-9]+.xml";
    private static final String LOG4J_FILE_NAME = "log4j.xml";
    private static File config_file = null;
    /**
    * @Synopsis  configure 
    * @Param File _file 
    * @Return 
    */
    public static void init(){
        LoggingInit init = new LoggingInit();
        File file = init.combined();
        config_file = init.modulate( file );
        DOMConfigurator.configure( config_file.getPath() );
    }

    /**
    * @Synopsis  getConfigFile 
    * @Return 
    */
    public static File getConfigFile(){
        return config_file;
    }

    /**
    * @Synopsis  replace path variables
    */
    class RealPath extends StrLookup{
        @Override
        public String lookup( String _key ){
            if( _key.trim().equals( "log_dir" ) ){
                return Path.singleInstance().getLogPath();
            }
            return "not-found";
        }
    }
    /**
    * @Synopsis  combined 
    * @Return 
    */
    public File combined(){
        File out = new File( Path.singleInstance().getLogConfPath() + File.separator + LOG4J_FILE_NAME );
        try{
            NodeCombiner node_combiner = new MergeCombiner();
            node_combiner.addListNode( "log4j:configuration" );
            CombinedConfiguration combined = new CombinedConfiguration( node_combiner );

            File dir = new File( Path.singleInstance().getLogConfPath() );
            IOFileFilter file_filter = new RegexFileFilter( CONFIG_FILE_NAME_PATTERN );
            IOFileFilter directory_filter = TrueFileFilter.INSTANCE;
            Collection< File > files = FileUtils.listFiles( dir, file_filter, directory_filter );
            for( File f : files ){
                XMLConfiguration c = new XMLConfiguration( f );
                combined.addConfiguration( c );
            }

            XMLConfiguration configuration = new XMLConfiguration( combined );
            configuration.setPublicID( "-//log4j/log4j Configuration//EN" );
            configuration.setSystemID( "log4j.dtd" );
            configuration.setRootElementName( "log4j:configuration" );

            ConfigurationInterpolator interpolator = configuration.getInterpolator();
            interpolator.registerLookup( "path", new RealPath() );(按你的规则替换成你的日志路劲）

            XMLConfiguration rs = ( XMLConfiguration ) configuration.interpolatedConfiguration();

            rs.save( out );
        }catch( ConfigurationException e ){
            throw new InitException( "combined exection", e );
        }
        return out;
    }
    /**
    * @Synopsis  modulate 
    * @Param File _file 
    * @Return 
    */
    public File modulate( File _file ){
        try{
            SAXReader reader = new SAXReader();
            Document dom = reader.read( _file );

            Element configuration = ( Element ) dom.selectSingleNode( "/configuration" );
            List appender_list = configuration.selectNodes( "appender" );
            List logger_list = configuration.selectNodes( "logger" );
            Node root = configuration.selectSingleNode( "root" );

            List< Element > elements = configuration.elements();
            elements.clear();
            for( Object object : appender_list ){
                elements.add( ( Element ) object );
            }
            for( Object object : logger_list ){
                elements.add( ( Element ) object );
            }
            elements.add( ( Element ) root );

            OutputFormat format = OutputFormat.createPrettyPrint();
            format.setIndentSize( 4 );
            XMLWriter writer = new XMLWriter( new FileOutputStream( _file ), format );
            writer.write( dom );
            writer.close();
        }catch( DocumentException e ){
            throw new InitException( "fromat exception", e );
        }catch( FileNotFoundException e ){
            throw new InitException( "fromat exception", e );
        }catch( UnsupportedEncodingException e ){
            throw new InitException( "fromat exception", e );
        }catch( IOException e ){
            throw new InitException( "fromat exception", e );
        }
        return _file;
    }

}