struts2配置log

Struts2初始化时，首先就会初始化log，看源码如下：

public void init(FilterConfig filterConfig) throws ServletException {
        InitOperations init = new InitOperations();
        Dispatcher dispatcher = null;
        try {
            FilterHostConfig config = new FilterHostConfig(filterConfig);
            init.initLogging(config);//初始化log
            dispatcher = init.initDispatcher(config);
            init.initStaticContentLoader(config, dispatcher);

            prepare = new PrepareOperations(filterConfig.getServletContext(), dispatcher);
            execute = new ExecuteOperations(filterConfig.getServletContext(), dispatcher);
            this.excludedPatterns = init.buildExcludedPatternsList(dispatcher);

            postInit(dispatcher, filterConfig);
        } finally {
            if (dispatcher != null) {
                dispatcher.cleanUpAfterInit();
            }
            init.cleanup();
        }
    }

public void initLogging( HostConfig filterConfig ) {
        String factoryName = filterConfig.getInitParameter("loggerFactory");
        if (factoryName != null) {
            try {
                Class cls = ClassLoaderUtil.loadClass(factoryName, this.getClass());
                LoggerFactory fac = (LoggerFactory) cls.newInstance();//必须是LoggerFactory的子类
                LoggerFactory.setLoggerFactory(fac);
            } catch ( InstantiationException e ) {
                System.err.println("Unable to instantiate logger factory: " + factoryName + ", using default");
                e.printStackTrace();
            } catch ( IllegalAccessException e ) {
                System.err.println("Unable to access logger factory: " + factoryName + ", using default");
                e.printStackTrace();
            } catch ( ClassNotFoundException e ) {
                System.err.println("Unable to locate logger factory class: " + factoryName + ", using default");
                e.printStackTrace();
            }
        }
    }

在web.xml中可以配置此log:

<filter>

        <filter-name>struts2</filter-name>

        <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>

        <init-param>
            <param-name>loggerFactory</param-name>
            <param-value>com.opensymphony.xwork2.util.logging.commons.CommonsLoggerFactory</param-value>
        </init-param>

    </filter>

具体使用方法：

    public static void test01() {
        Logger log = LoggerFactory.getLogger(Test.class);
        //必须是#加上数字的形式
        log.info("#0t#1e#2st#3#4#5#6#7#8#9#10", new String[]{"a","b","c","d","e","f","g","h","i","j","k"});
        log.error("#0t#1e#2st#3#4#5#6#7#8#9#10", new String[]{"a","b","c","d","e","f","g","h","i","j","k"});
        log.warn("#0t#1e#2st#3#4#5#6#7#8#9#10", new String[]{"a","b","c","d","e","f","g","h","i","j","k"});
        log.fatal("#0t#1e#2st#3#4#5#6#7#8#9#10", new String[]{"a","b","c","d","e","f","g","h","i","j","k"});
    }

输出如下：

8 26, 2014 12:57:44 午後 test.Test info
情報: atbecstdefghijb0
8 26, 2014 12:57:44 午後 test.Test error
SEVERE: atbecstdefghijb0
8 26, 2014 12:57:44 午後 test.Test warn
WARNING: atbecstdefghijb0
8 26, 2014 12:57:44 午後 test.Test fatal
SEVERE: atbecstdefghijb0