仿log4j定制自己的Log工具类
原由：
log4j是很强大，可每次使用还要加入log4j包，还要使用配置文件。对于一般的小工具或小项目感觉还是有点大动作了。而且在使用log4j时每次还要每取个实例再传个参数来记录，感觉有点麻烦。就自己仿log4j使用jdk logger定制了一个自己的记录工具类。
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工具类特点：
无配置文件，默认为info级别，控制台输出，无需改动即可满足一般开发需要。。 直接打log，在java文件中直接使用
Log.info("test"); 即可，如果输出到文件，则自动按不同级别生成不同记录文件 使用四个级别的log。分别为 Log.debug(""); Log.info(""); Log.warn(""); Log.error(""); 对于一般项目已经足够。 log输出方式有两种，控制台输出和文件输出。输出格式两者统一。文件输出时的文件路径可定制。默认为class文件夹下,名称格式为 等级_时间.log 如: INFO_2011-10-12.log Log.debug("debug"); Log.info("info"); Log.info("info1"); Log.warn("warn"); Log.error("error"); try { throw new Exception("exception"); } catch (Exception e) { Log.error(e); }?结果：2012-03-02 16:25:03 NewClass.java(Line:19): [INFO] info2012-03-02 16:25:03 NewClass.java(Line:20): [INFO] info12012-03-02 16:25:03 NewClass.java(Line:21): [WARN] warn2012-03-02 16:25:03 NewClass.java(Line:22): [ERROR] error2012-03-02 16:25:03 NewClass.java(Line:26):?java.lang.Exception: exceptionat com.dfhstudio.thoughtfly.util.NewClass.main(NewClass.java:24)import java.io.BufferedOutputStream;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.OutputStream;import java.io.PrintWriter;import java.io.StringWriter;import java.nio.channels.FileChannel;import java.nio.channels.FileLock;import java.security.AccessController;import java.security.PrivilegedAction;import java.text.SimpleDateFormat;import java.util.ArrayList;import java.util.Date;import java.util.logging.ConsoleHandler;import java.util.logging.ErrorManager;import java.util.logging.Formatter;import java.util.logging.Handler;import java.util.logging.Level;import java.util.logging.LogManager;import java.util.logging.LogRecord;import java.util.logging.Logger;import java.util.logging.StreamHandler;/** * <b>自定义LOG工具，丁风华</b> * <ul> * <b>特点</b> * <li>无配置文件，默认为info级别，控制台输出，无需改动即可满足一般开发需要。。</li> * <li>直接打log，在java文件中直接使用 <code>Log.info("test");</code> 即可，如果输出到文件，则自动按不同级别生成不同记录文件</li> * <li>使用四个级别的log。分别为 <code>Log.debug(""); Log.info(""); Log.warn(""); Log.error("");</code> 对于一般项目已经足够。</li> * <li>log输出方式有两种，控制台输出和文件输出。输出格式两者统一。文件输出时的文件路径可定制。默认为class文件夹下,名称格式为 等级_时间.log 如: INFO_2011-10-12.log</li> * </ul> * <ul> * <b>输出到文件使用方法</b><br> * 更改构造器方法中的数据. private Log()<br> * 1.设置输出级别: setLogLevel("info");<br> * 2.设置输出到文件: HANDLER_FILE = true;<br> * 3.设置设置文件保存路径: LOG_FILE_PATH = "D:\\log\";<br> * 4.设置每个文件的最大值: FILE_SIZE = 2000000; // *** 每个文件最大2M <br> * 5.设置每天最多生成多少个文件数量: FILE_MAX = 10; // *** 每天最多生成10个文件,最多不可超过100<br> * 6.设置log文件后缀名: LOG_FILE_LASTNAME = ".log"; * </ul> * <ul> * <b>更改记录内容的格式</b><br> * 可更改 dealInfoFormat 方法中的 formatMessage 变量值即可。 * </ul> * * @author DingFengHua */public class Log { private Log() { setLogLevel("INFO"); HANDLER_CONSOLE = true; // *** 控制台输出 HANDLER_FILE = false; // *** 文件输出 // *** 如果不想使用文件打LOG，即 HANDLER_FILE = false;，则不用关心以下数据 // *** 自动创建路径文件夹 if (HANDLER_FILE) { // *** 1. LOG文件夹在class文件夹目录下 // LOG_FILE_PATH = new File(Log.class.getClassLoader().getResource(".").getFile()).toString() + "/log/"; // *** 2. 如果是web项目，LOG文件夹在项目根目录下 LOG_FILE_PATH = new File(Log.class.getClassLoader().getResource("/").getFile()).toString() + "/../../log/"; FILE_SIZE = 2000000; // *** 每个文件最大2M FILE_MAX = 10; // *** 每天最多生成10个文件,最多不可超过100 LOG_FILE_LASTNAME = ".log"; // *** 文件后缀名 } } /* * 以下内容不必更改********************************************************************************************************** */ /* ************************************************************************************************************************* */ private String getLogFileName(String level) { String firtFileName = LOG_FILE_PATH + level + "_" + getDateFormat("yyyy-MM-dd", new Date()) + LOG_FILE_LASTNAME; return firtFileName; } /** * 从字符串转换为JDKLOG的LEVEL等级 * * @param strLevel 自定义的等级字符串 * @return JDKLOG的等级 */ private Level getLogLevelFromString(String strLevel) { Level l = Level.INFO; if (LEVEL_DEBUG.equalsIgnoreCase(strLevel)) { l = Level.FINE; } if (LEVEL_WARN.equalsIgnoreCase(strLevel)) { l = Level.WARNING; } if (LEVEL_ERROR.equalsIgnoreCase(strLevel)) { l = Level.SEVERE; } return l; } /** * 低等级记录 * * @param info 记录信息 */ public static void debug(String info) { INSTANCE.log(LEVEL_DEBUG, "[" + LEVEL_DEBUG + "] " + info, null); } /** * 普通信息记录 * * @param info 记录信息 */ public static void info(String info) { INSTANCE.log(LEVEL_INFO, "[" + LEVEL_INFO + "] " + info, null); } /** * 警告信息记录 * * @param info 记录信息 */ public static void warn(String info) { INSTANCE.log(LEVEL_WARN, "[" + LEVEL_WARN + "] " + info, null); } /** * 错误信息记录 * * @param info 记录信息 */ public static void error(String info) { INSTANCE.log(LEVEL_ERROR, "[" + LEVEL_ERROR + "] " + info, null); } /** * 错误信息记录 * * @param info 异常 */ public static void error(Throwable info) { INSTANCE.log(LEVEL_ERROR, "", info); } /** * 处理记录信息 * * @param level 信息等级 * @param info 信息内容 * @param exception 异常信息 */ private void log(String level, String info, Throwable exception) { checkFileDate(level); Logger logger = Logger.getLogger(level); if (!logList.contains(level)) { logList.add(level); dealHander(logger); dealInfoFormat(logger); } logger.setLevel(logOutPutLevel); logger.log(getLogLevelFromString(level), info, exception); } /** * 内容格式化，默认内容格式为 时间 文件名(行数):[等级] 内容 * * @param logger JDK Log */ private void dealInfoFormat(Logger logger) { logger.setUseParentHandlers(false); StackTraceElement[] stackTraceElement = Thread.currentThread().getStackTrace(); final StackTraceElement element = stackTraceElement[stackTraceElement.length - 1]; for (Handler handler : logger.getHandlers()) { handler.setFormatter(new Formatter() { @Override public String format(LogRecord record) { StringBuilder formatMessage = new StringBuilder(); formatMessage.append(getDateFormat("yyyy-MM-dd HH:mm:ss", new Date())); formatMessage.append(" ").append(element.getFileName()).append("(Line:") .append(element.getLineNumber()).append("):").append(" ") .append(record.getMessage()).append("\n"); if (record.getThrown() != null) { try { StringWriter sw = new StringWriter(); PrintWriter pw = new PrintWriter(sw); record.getThrown().printStackTrace(pw); pw.close(); formatMessage.append(sw.toString()); } catch (Exception ex) { } } return formatMessage.toString(); } }); } } /** * 输出处理，控制台和文件,文件输出的文件名格式为 等级_yyyy-MM-dd.log 如果有多个文件，会在文件名后递增数字 * * @param logger jdk log */ private void dealHander(Logger logger) { boolean alreadyHasConsole = false, alreadyHasFile = false; Handler[] handlers = logger.getHandlers(); for (int i = 0; i < handlers.length; i++) { if (handlers[i] instanceof ConsoleHandler) { alreadyHasConsole = true; } else if (handlers[i] instanceof MyFileHandler) { alreadyHasFile = true; } } if (HANDLER_CONSOLE && !alreadyHasConsole) { ConsoleHandler ch = new ConsoleHandler(); ch.setLevel(logOutPutLevel); logger.addHandler(ch); } if (HANDLER_FILE && !alreadyHasFile) { String file = getLogFileName(logger.getName()); File f = new File(LOG_FILE_PATH); if (!f.isDirectory()) { f.mkdirs(); f.mkdir(); } try { MyFileHandler fh = new MyFileHandler(file, FILE_SIZE, FILE_MAX, true); fh.setLevel(logOutPutLevel); logger.addHandler(fh); } catch (IOException ex) { Logger.getLogger(Log.class.getName()).log(Level.SEVERE, null, ex); } catch (SecurityException ex) { Logger.getLogger(Log.class.getName()).log(Level.SEVERE, null, ex); } } } /** * 格式化时间到字符串 * * @param pattern 格式 * @param date 时间 * @return 格式化的字符串 */ private String getDateFormat(String pattern, Date date) { format.applyPattern(pattern); return format.format(date); } /** * 设置输出等级 * * @param level 自定义等级,可使用 debug,info,warn,error 忽略大小写 */ public final void setLogLevel(String level) { logOutPutLevel = getLogLevelFromString(level); } private void checkFileDate(String level) { File f = new File(getLogFileName(level)); if (!f.exists()) { for (Handler handler : Logger.getLogger(level).getHandlers()) { handler.close(); } logList.remove(level); } } private static String LOG_FILE_PATH; private Level logOutPutLevel; private int FILE_SIZE; private int FILE_MAX; private boolean HANDLER_FILE = false; private boolean HANDLER_CONSOLE = false; private static ArrayList<String> logList = new ArrayList<String>(); private String LOG_FILE_LASTNAME; private static String LEVEL_DEBUG = "DEBUG"; private static String LEVEL_INFO = "INFO"; private static String LEVEL_WARN = "WARN"; private static String LEVEL_ERROR = "ERROR"; private static Log INSTANCE = new Log(); SimpleDateFormat format = new SimpleDateFormat();}/** * 自定义文件输出管理类，参考JDK FileHandler实现 * * @author DingFengHua */class MyFileHandler extends StreamHandler { private MeteredStream meter; private boolean append; private int limit; // zero => no limit. private int count; private String pattern; private String lockFileName; private FileOutputStream lockStream; private File files[]; private static final int MAX_LOCKS = 100; private static java.util.HashMap<String, String> locks = new java.util.HashMap<String, String>(); private class MeteredStream extends OutputStream { OutputStream out; int written; MeteredStream(OutputStream out, int written) { this.out = out; this.written = written; } public void write(int b) throws IOException { out.write(b); written++; } @Override public void write(byte buff[]) throws IOException { out.write(buff); written += buff.length; } @Override public void write(byte buff[], int off, int len) throws IOException { out.write(buff, off, len); written += len; } @Override public void flush() throws IOException { out.flush(); } @Override public void close() throws IOException { out.close(); } } private void open(File fname, boolean append) throws IOException { int len = 0; if (append) { len = (int) fname.length(); } FileOutputStream fout = new FileOutputStream(fname.toString(), append); BufferedOutputStream bout = new BufferedOutputStream(fout); meter = new MeteredStream(bout, len); setOutputStream(meter); } public MyFileHandler() throws IOException, SecurityException { openFiles(); } public MyFileHandler(String pattern) throws IOException, SecurityException { if (pattern.length() < 1) { throw new IllegalArgumentException(); } this.pattern = pattern; this.limit = 0; this.count = 1; openFiles(); } public MyFileHandler(String pattern, boolean append) throws IOException, SecurityException { if (pattern.length() < 1) { throw new IllegalArgumentException(); } this.pattern = pattern; this.limit = 0; this.count = 1; this.append = append; openFiles(); } public MyFileHandler(String pattern, int limit, int count) throws IOException, SecurityException { if (limit < 0 || count < 1 || pattern.length() < 1) { throw new IllegalArgumentException(); } this.pattern = pattern; this.limit = limit; this.count = count; openFiles(); } public MyFileHandler(String pattern, int limit, int count, boolean append) throws IOException, SecurityException { if (limit < 0 || count < 1 || pattern.length() < 1) { throw new IllegalArgumentException(); } this.pattern = pattern; this.limit = limit; this.count = count; this.append = append; openFiles(); } private void openFiles() throws IOException { LogManager manager = LogManager.getLogManager(); manager.checkAccess(); if (count < 1) { throw new IllegalArgumentException("file count = " + count); } if (limit < 0) { limit = 0; } InitializationErrorManager em = new InitializationErrorManager(); setErrorManager(em); int unique = -1; for (;;) { unique++; if (unique > MAX_LOCKS) { throw new IOException("Couldn't get lock for " + pattern); } lockFileName = generate(pattern, 0, unique).toString() + ".lck"; synchronized (locks) { if (locks.get(lockFileName) != null) { continue; } FileChannel fc; try { lockStream = new FileOutputStream(lockFileName); fc = lockStream.getChannel(); } catch (IOException ix) { continue; } try { FileLock fl = fc.tryLock(); if (fl == null) { continue; } } catch (IOException ix) { } locks.put(lockFileName, lockFileName); break; } } files = new File[count]; for (int i = 0; i < count; i++) { files[i] = generate(pattern, i, unique); } if (append) { open(files[0], true); } else { rotate(); } Exception ex = em.lastException; if (ex != null) { if (ex instanceof IOException) { throw (IOException) ex; } else if (ex instanceof SecurityException) { throw (SecurityException) ex; } else { throw new IOException("Exception: " + ex); } } setErrorManager(new ErrorManager()); } private File generate(String pattern, int generation, int unique) throws IOException { File file = null; String word = ""; int ix = 0; boolean sawg = false; boolean sawu = false; while (ix < pattern.length()) { char ch = pattern.charAt(ix); ix++; char ch2 = 0; if (ix < pattern.length()) { ch2 = Character.toLowerCase(pattern.charAt(ix)); } if (ch == '/') { if (file == null) { file = new File(word); } else { file = new File(file, word); } word = ""; continue; } else if (ch == '%') { if (ch2 == 't') { String tmpDir = System.getProperty("java.io.tmpdir"); if (tmpDir == null) { tmpDir = System.getProperty("user.home"); } file = new File(tmpDir); ix++; word = ""; continue; } else if (ch2 == 'h') { file = new File(System.getProperty("user.home")); if (isSetUID()) { throw new IOException("can't use %h in set UID program"); } ix++; word = ""; continue; } else if (ch2 == 'g') { word = word + generation; sawg = true; ix++; continue; } else if (ch2 == 'u') { word = word + unique; sawu = true; ix++; continue; } else if (ch2 == '%') { word = word + "%"; ix++; continue; } } word = word + ch; } if (count > 1 && generation > 0 && !sawg) { word = word + "." + generation; } if (unique > 0 && !sawu) { word = word + "." + unique; } if (word.length() > 0) { if (file == null) { file = new File(word); } else { file = new File(file, word); } } return file; } private synchronized void rotate() { Level oldLevel = getLevel(); setLevel(Level.OFF); super.close(); for (int i = count - 2; i >= 0; i--) { File f1 = files[i]; File f2 = files[i + 1]; if (f1.exists()) { if (f2.exists()) { f2.delete(); } f1.renameTo(f2); } } try { open(files[0], false); } catch (IOException ix) { reportError(null, ix, ErrorManager.OPEN_FAILURE); } setLevel(oldLevel); } @Override public synchronized void publish(LogRecord record) { if (!isLoggable(record)) { return; } super.publish(record); flush(); if (limit > 0 && meter.written >= limit) { AccessController.doPrivileged(new PrivilegedAction<Object>() { public Object run() { rotate(); return null; } }); } } @Override public synchronized void close() throws SecurityException { super.close(); if (lockFileName == null) { return; } try { lockStream.close(); } catch (Exception ex) { } synchronized (locks) { locks.remove(lockFileName); } new File(lockFileName).delete(); lockFileName = null; lockStream = null; } private static class InitializationErrorManager extends ErrorManager { Exception lastException; @Override public void error(String msg, Exception ex, int code) { lastException = ex; } } private static native boolean isSetUID();}?