Java内置Logger的项目级完整代码使用流程

此前因其它事务，已经有很长时间没作Java开发。近日要用Java构建一个Html5移动小程序后台。

因为是小程序嘛，用于移动端，处理客户端请求都是返回json，自然就用不上SSH那么高大尚，那么耗内存，那么复杂，那么开发效率慢 的框架。

同时，也想 回归本原，写一些简单代码来架建一个 restful 框架雏型。

本原想用log4j构建log系统，下载最新版，一看引包达 1M 多，恼了，不就是写条log，用得 着吗？！我整个项目把自己的代码打成jar包还没有一兆呢！

又看了下common-logging，它要不就是 没干啥事，要不就是 需要挂载其它包。

参考了网上的资料，决定自己封装一个JDK Log

下面代码已经调好了，不客气！ (如果你也有类似的看法)

1，新建 SysLog.java ，键入下面的代码。用于 getLogger

2，新建 SysLogFormatter.java，用于格式化输入。我想你是不会满意jdk的默认log输出。这是我从SimpleFormatter摸索出来的。

3，新建 logger.properties，放到 src 或 WEB-INF 目录下。用于格式化输出，和输出到file

SysLog.java

import java.io.InputStream;import java.io.PrintWriter;import java.io.StringWriter;import java.util.Date;import java.util.logging.Formatter;import java.util.logging.LogManager;import java.util.logging.LogRecord;import java.util.logging.Logger;public class SysLog {private static SysLog log = null;public static SysLog instance() {if (log == null) {//synchronized SysLog.classlog = new SysLog();}return log;}public SysLog() {InputStream is = null;        try {        LogManager.getLogManager().readConfiguration(SysLog.class.getClass().getResourceAsStream("/logger.properties"));                    } catch (Exception e) {            System.err.println("input properties file is error.\n" + e.toString());            e.printStackTrace();                    } finally {        if( is != null ) {        try {        is.close();} catch (Exception e2) {e2.printStackTrace();}                }        }}public Logger get_loger(Class<?> clazz) {return get_loger(clazz.getName());}public Logger get_loger(String clazz) {// LogManager.getLogManager().getLogger(name)return Logger.getLogger(clazz);}public static Logger getLoger(Class<?> clazz) {return instance().get_loger(clazz);}public static Logger getLoger(String clazz) {return instance().get_loger(clazz);}}

SysLogFormater.java

package sx.cms.util;import java.io.PrintWriter;import java.io.StringWriter;import java.util.Date;import java.util.logging.Formatter;import java.util.logging.LogRecord;/** * this code was from copy from java.util.logging.SimpleFormatter */public class SysLogFormatter extends Formatter {    //private static final String format = "%1$tb %1$td, %1$tY %1$tl:%1$tM:%1$tS %1$Tp %2$s%n%4$s: %5$s%6$s%n";//private static final String format = "%1$tY/%1$tb/%1$td/%1$Tp/%1$tl:%1$tM:%1$tS %2$s[%4$s]\t%5$s%6$s%n";private static final String format = "%1$tY/%1$tm/%1$td/%1$tH:%1$tM:%1$tS %2$s[%4$s]\t%5$s%6$s%n";    private final Date dat = new Date();    public synchronized String format(LogRecord record) {        dat.setTime(record.getMillis());        String source;        if (record.getSourceClassName() != null) {            source = record.getSourceClassName();            if (record.getSourceMethodName() != null) {               source += " " + record.getSourceMethodName();            }        } else {            source = record.getLoggerName();        }        String message = formatMessage(record);        String throwable = "";        if (record.getThrown() != null) {            StringWriter sw = new StringWriter();            PrintWriter pw = new PrintWriter(sw);            pw.println();            record.getThrown().printStackTrace(pw);            pw.close();            throwable = sw.toString();        }        return String.format(format,                             dat,                             source,                             record.getLoggerName(),                             //record.getLevel().getLocalizedLevelName(),                             record.getLevel().getName(),                             message,                             throwable);    }}

logger.properties

handlers = java.util.logging.ConsoleHandler,java.util.logging.FileHandlerjava.util.logging.ConsoleHandler.formatter = project.your.SysLogFormatterjava.util.logging.ConsoleHandler.level = CONFIG# Level.INFO #log out filejava.util.logging.FileHandler.pattern = my.log%g.log  java.util.logging.FileHandler.formatter = sx.cms.util.SysLogFormatterjava.util.logging.FileHandler.limit = 104857600java.util.logging.FileHandler.count = 3java.util.logging.FileHandler.append = truejava.util.logging.FileHandler.level = INFO LOGGER.level = WARNING

测试和使用

//测试和使用public static void main(String[] args) {Logger log = SysLog.getLoger(Main.class);log.info("log 中国" + System.currentTimeMillis());}