Android：log工具類

package com.example.customalarm.utils;

import android.text.TextUtils;
import android.util.Log;

/**
 * LogUtils工具說明: 
 * 1 只輸出等級大於等於LEVEL的日誌 
 *   所以在開發和產品發佈後通過修改LEVEL來選擇性輸出日誌.
 *   當LEVEL=NOTHING則屏蔽了所有的日誌. 
 * 2 v,d,i,w,e均對應兩個方法. 
 *   若不設置TAG或者TAG爲空則爲設置默認TAG
 * 
 * @author BiHaidong
 * @date 2015-11-17 13:58:49
 * 
 */
public class LogUtils {
	public static final int VERBOSE = 1;
	public static final int DEBUG = 2;
	public static final int INFO = 3;
	public static final int WARN = 4;
	public static final int ERROR = 5;
	public static final int NOTHING = 6;
	public static final int LEVEL = VERBOSE;
	public static final String SEPARATOR = ",";

	public static void v(String message) {
		if (LEVEL <= VERBOSE) {
			StackTraceElement stackTraceElement = Thread.currentThread().getStackTrace()[3];
			String tag = getDefaultTag(stackTraceElement);
			Log.v(tag, getLogInfo(stackTraceElement) + message);
		}
	}

	public static void v(String tag, String message) {
		if (LEVEL <= VERBOSE) {
			StackTraceElement stackTraceElement = Thread.currentThread().getStackTrace()[3];
			if (TextUtils.isEmpty(tag)) {
				tag = getDefaultTag(stackTraceElement);
			}
			Log.v(tag, getLogInfo(stackTraceElement) + message);
		}
	}

	public static void d(String message) {
		if (LEVEL <= DEBUG) {
			StackTraceElement stackTraceElement = Thread.currentThread().getStackTrace()[3];
			String tag = getDefaultTag(stackTraceElement);
			Log.d(tag, getLogInfo(stackTraceElement) + message);
		}
	}

	public static void d(String tag, String message) {
		if (LEVEL <= DEBUG) {
			StackTraceElement stackTraceElement = Thread.currentThread().getStackTrace()[3];
			if (TextUtils.isEmpty(tag)) {
				tag = getDefaultTag(stackTraceElement);
			}
			Log.d(tag, getLogInfo(stackTraceElement) + message);
		}
	}

	public static void i(String message) {
		if (LEVEL <= INFO) {
			StackTraceElement stackTraceElement = Thread.currentThread().getStackTrace()[3];
			String tag = getDefaultTag(stackTraceElement);
			Log.i(tag, getLogInfo(stackTraceElement) + message);
		}
	}

	public static void i(String tag, String message) {
		if (LEVEL <= INFO) {
			StackTraceElement stackTraceElement = Thread.currentThread().getStackTrace()[3];
			if (TextUtils.isEmpty(tag)) {
				tag = getDefaultTag(stackTraceElement);
			}
			Log.i(tag, getLogInfo(stackTraceElement) + message);
		}
	}

	public static void w(String message) {
		if (LEVEL <= WARN) {
			StackTraceElement stackTraceElement = Thread.currentThread().getStackTrace()[3];
			String tag = getDefaultTag(stackTraceElement);
			Log.w(tag, getLogInfo(stackTraceElement) + message);
		}
	}

	public static void w(String tag, String message) {
		if (LEVEL <= WARN) {
			StackTraceElement stackTraceElement = Thread.currentThread().getStackTrace()[3];
			if (TextUtils.isEmpty(tag)) {
				tag = getDefaultTag(stackTraceElement);
			}
			Log.w(tag, getLogInfo(stackTraceElement) + message);
		}
	}

	public static void e(String tag, String message) {
		if (LEVEL <= ERROR) {
			StackTraceElement stackTraceElement = Thread.currentThread().getStackTrace()[3];
			if (TextUtils.isEmpty(tag)) {
				tag = getDefaultTag(stackTraceElement);
			}
			Log.e(tag, getLogInfo(stackTraceElement) + message);
		}
	}

	/**
	 * 獲取默認的TAG名稱. 
	 * 比如在MainActivity.java中調用了日誌輸出. 
	 * 則TAG爲MainActivity
	 */
	public static String getDefaultTag(StackTraceElement stackTraceElement) {
		String fileName = stackTraceElement.getFileName();
		String stringArray[] = fileName.split("\\.");
		String tag = stringArray[0];
		return tag;
	}

	/**
	 * 輸出日誌所包含的信息
	 */
	public static String getLogInfo(StackTraceElement stackTraceElement) {
		StringBuilder logInfoStringBuilder = new StringBuilder();
		// 獲取線程名
		String threadName = Thread.currentThread().getName();
		// 獲取線程ID
		long threadID = Thread.currentThread().getId();
		// 獲取文件名.即xxx.java
		String fileName = stackTraceElement.getFileName();
		// 獲取類名.即包名+類名
		String className = stackTraceElement.getClassName();
		// 獲取方法名稱
		String methodName = stackTraceElement.getMethodName();
		// 獲取生日輸出行數
		int lineNumber = stackTraceElement.getLineNumber();

		logInfoStringBuilder.append("[ ");
		logInfoStringBuilder.append("threadID=" + threadID).append(SEPARATOR);
		logInfoStringBuilder.append("threadName=" + threadName).append(SEPARATOR);
		logInfoStringBuilder.append("fileName=" + fileName).append(SEPARATOR);
		logInfoStringBuilder.append("className=" + className).append(SEPARATOR);
		logInfoStringBuilder.append("methodName=" + methodName).append(SEPARATOR);
		logInfoStringBuilder.append("lineNumber=" + lineNumber);
		logInfoStringBuilder.append(" ] ");
		return logInfoStringBuilder.toString();
	}

}