Android输出调试日志至文件中

       本博客讲述的是android输出日志到文件中，不依赖于任何类，仅需配置读写外部存储卡的权限，可叠加输出日志文件，可区别调试模式与正式发布版本进行选择性输出。可直接在项目中使用。下面贴上代码,代码可到(LogUtils)下载,密码:hvqw。

1.申请权限

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission></uses-permission>

2.核心代码

import java.io.BufferedWriter;import java.io.File;import java.io.FileOutputStream;import java.io.FileWriter;import java.io.IOException;import java.io.OutputStreamWriter;import java.io.RandomAccessFile;import java.text.SimpleDateFormat;import java.util.Date;import android.annotation.SuppressLint;import android.os.Environment;/** * 日志输出类,输出日志至文件中 * * @author yzy * */public class LogUtils {public static String LOG_PATH = "";public static String LOG_NAME = "/debug.log";private static String INFO = "info";private static String DEBUG = "debug";private static String WARN = "warn";private static String VERBOSE = "verbose";private static String ERROR = "error";private static final boolean isDebug = true ;static {if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){LOG_PATH = Environment.getExternalStorageDirectory() + "/LogUtils" + "/.log" ;}else{LOG_PATH = "/LogUtils" + "/.log" ;}}/** * 初始化保存日志的文件 * @param path * @param name */public static void init(String path,String name){LOG_PATH = path ;LOG_NAME = name ;}public static void i(String content) {saveLog(INFO, content);}public static void v(String content) {saveLog(VERBOSE, content);}public static void d(String content) {saveLog(DEBUG, content);}public static void e(String content) {saveLog(ERROR, content);}public static void w(String content) {saveLog(WARN, content);}@SuppressLint("SimpleDateFormat") public static void saveLog(String type, String content) {if(isDebug){//当当前是debug时,才进入保存日志操作appendToFile_Third(LOG_PATH + LOG_NAME, new SimpleDateFormat("yyyy-MM-dd HH:mm:ss:SSS").format(new Date(System.currentTimeMillis())) + "(" + type + "):" + content + "\r\n");}}/** * 第一种方式追加文本至文件中(随机文件流追加) * * @param filePath * @param content */public static void appendToFile_One(String filePath, String content) {RandomAccessFile ranFile = null;try {File file = new File(filePath);if (!file.exists()) {file.getParentFile().mkdirs();file.createNewFile();}ranFile = new RandomAccessFile(file, "rw");long fileLength = ranFile.length();// 获取文件文本的长度ranFile.seek(fileLength); // 设置游标至文件的尾部ranFile.writeBytes(content);} catch (IOException e) {e.printStackTrace();} finally {try {if (ranFile != null) {ranFile.close();}} catch (IOException e) {e.printStackTrace();}}}/** * 第二种方式追加文本至文件中(BufferedWriter追加) * * @param filePath * @param content */public static void appendToFile_Two(String filePath, String content) {BufferedWriter bufferedWriter = null;try {File file = new File(filePath);if (!file.exists()) {file.getParentFile().mkdirs();file.createNewFile();}bufferedWriter = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file)));bufferedWriter.write(content);} catch (IOException e) {e.printStackTrace();} finally {if (bufferedWriter != null) {try {bufferedWriter.close();} catch (IOException e) {e.printStackTrace();}}}}/** * 第三种方式追加文本至文件中(BufferedWriter追加) * * @param filePath * @param content */public static void appendToFile_Third(String filePath, String content) {FileWriter fileWriter = null;try {File file = new File(filePath);if (!file.exists()) {file.getParentFile().mkdirs();file.createNewFile();}fileWriter = new FileWriter(file, true);// true表示附加fileWriter.append(content);} catch (IOException e) {e.printStackTrace();} finally {if (fileWriter != null) {try {fileWriter.close();} catch (IOException e) {e.printStackTrace();}}}}}