Android輸出調試日誌至文件中

       本博客講述的是android輸出日誌到文件中，不依賴於任何類，僅需配置讀寫外部存儲卡的權限，可疊加輸出日誌文件，可區別調試模式與正式發佈版本進行選擇性輸出。可直接在項目中使用。下面貼上代碼,代碼可到(LogUtils)下載,密碼:hvqw。

1.申請權限

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

2.核心代碼

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; /** * 日誌輸出類,輸出日誌至文件中 * * @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" ; } } /** * 初始化保存日誌的文件 * @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){//噹噹前是debug時,才進入保存日誌操作 appendToFile_Third(LOG_PATH + LOG_NAME, new SimpleDateFormat("yyyy-MM-dd HH:mm:ss:SSS").format(new Date( System.currentTimeMillis())) + "(" + type + "):" + content + "\r\n"); } } /** * 第一種方式追加文本至文件中(隨機文件流追加) * * @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();// 獲取文件文本的長度 ranFile.seek(fileLength); // 設置遊標至文件的尾部 ranFile.writeBytes(content); } catch (IOException e) { e.printStackTrace(); } finally { try { if (ranFile != null) { ranFile.close(); } } catch (IOException e) { e.printStackTrace(); } } } /** * 第二種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(); } } } } /** * 第三種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(); } } } } }