編輯:關於Android編程
把自己應用的調試信息寫入到SD卡中。
package com.sdmc.hotel.util; import java.io.BufferedReader; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStreamReader; import android.content.Context; import android.os.Environment; import android.util.Log; /** * log日志統計保存 * 會打印i,e,w,不會打印d * 每次開啟應用,就會把上次的log信息覆蓋 * @author way * */ public class LogcatHelper { private static LogcatHelper INSTANCE = null; private static String PATH_LOGCAT; private LogDumper mLogDumper = null; private int mPId; /** * * 初始化目錄 * * */ public void init(Context context) { if (Environment.getExternalStorageState().equals( Environment.MEDIA_MOUNTED)) {// 優先保存到SD卡中 PATH_LOGCAT = Environment.getExternalStorageDirectory() .getAbsolutePath() + File.separator + "miniGPS"; } else {// 如果SD卡不存在,就保存到本應用的目錄下 PATH_LOGCAT = context.getFilesDir().getAbsolutePath() + File.separator + "miniGPS"; } File file = new File(PATH_LOGCAT); if (!file.exists()) { file.mkdirs(); } } public static LogcatHelper getInstance(Context context) { if (INSTANCE == null) { INSTANCE = new LogcatHelper(context); } return INSTANCE; } private LogcatHelper(Context context) { init(context); mPId = android.os.Process.myPid(); } public void start() { if (mLogDumper == null){ mLogDumper = new LogDumper(String.valueOf(mPId), PATH_LOGCAT); } Log.i("path", PATH_LOGCAT);///storage/sdcard0/miniGPS mLogDumper.start(); } public void stop() { if (mLogDumper != null) { mLogDumper.stopLogs(); mLogDumper = null; } } private class LogDumper extends Thread { private Process logcatProc; private BufferedReader mReader = null; private boolean mRunning = true; String cmds = null; private String mPID; private FileOutputStream out = null; public LogDumper(String pid, String dir) { mPID = pid; try { out = new FileOutputStream(new File(dir, "GPS-" + MyDate.getFileName() + ".log")); } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } /** * * 日志等級:*:v , *:d , *:w , *:e , *:f , *:s * * 顯示當前mPID程序的 E和W等級的日志. * * */ // cmds = "logcat *:e *:w | grep \"(" + mPID + ")\""; // cmds = "logcat | grep \"(" + mPID + ")\"";//打印所有日志信息 // cmds = "logcat -s way";//打印標簽過濾信息 cmds = "logcat *:e *:i | grep \"(" + mPID + ")\"";//會打印i,e,w,不會打印d } public void stopLogs() { mRunning = false; } @Override public void run() { try { logcatProc = Runtime.getRuntime().exec(cmds); mReader = new BufferedReader(new InputStreamReader( logcatProc.getInputStream()), 1024); String line = null; while (mRunning && (line = mReader.readLine()) != null) { if (!mRunning) { break; } if (line.length() == 0) { continue; } if (out != null && line.contains(mPID)) { out.write((MyDate.getDateEN() + " " + line + "\n") .getBytes()); } } } catch (IOException e) { e.printStackTrace(); } finally { if (logcatProc != null) { logcatProc.destroy(); logcatProc = null; } if (mReader != null) { try { mReader.close(); mReader = null; } catch (IOException e) { e.printStackTrace(); } } if (out != null) { try { out.close(); } catch (IOException e) { e.printStackTrace(); } out = null; } } } } }
系統權限
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <uses-permission android:name="android.permission.READ_LOGS" />
時間工具類:
package com.sdmc.hotel.util; import java.text.SimpleDateFormat; import java.util.Date; public class MyDate { public static String getFileName() { SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd"); String date = format.format(new Date(System.currentTimeMillis())); return date;// 2012年10月03日 23:41:31 } public static String getDateEN() { SimpleDateFormat format1 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); String date1 = format1.format(new Date(System.currentTimeMillis())); return date1;// 2012-10-03 23:41:31 } }
方法的調用:
public class MyApplication extends Application { @Override public void onCreate() { LogcatHelper.getInstance(this).start(); } }
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