Android将应用log信息保存文件

相信大家在做应用调试的时候，不可能时时通过USB线连着电脑去查看log信息，所以，将应用的log信息保存到手机本地就很有必要了，有助我们从这些log信息中提取有用的部分，以解决一些bug，下面我把网上分享的代码中作了一些精简，作为开发者使用，个人觉得没必要通过用户上传给我们，用户上传的不需要这么庞大的log信息，仅仅那部分崩溃的log信息即可，可参考我的另外一篇blog:http://blog.csdn.net/weidi1989/article/details/7927273。

好了，废话不多说，直接分享封装好的log信息类：LogcatHelper

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package com.way.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;

/**

* log日志统计保存

*

* @author way

*

*/

public class LogcatHelper {

private static LogcatHelper INSTANCE = null;

private static String PATH_LOGCAT;

private LogDumper mLogDumper = null;

private int mPId;

/**

*

* 初始化目录

*

* */

public void init(Context context) {

if (Environment.getExternalStorageState().equals(

Environment.MEDIA_MOUNTED)) {// 优先保存到SD卡中

PATH_LOGCAT = Environment.getExternalStorageDirectory()

.getAbsolutePath() + File.separator + "miniGPS";

} else {// 如果SD卡不存在，就保存到本应用的目录下

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);

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();

}

/**

*

* 日志等级：*:v , *:d , *:w , *:e , *:f , *:s

*

* 显示当前mPID程序的 E和W等级的日志.

*

* */

// cmds = "logcat *:e *:w | grep \"(" + mPID + ")\"";

// cmds = "logcat | grep \"(" + mPID + ")\"";//打印所有日志信息

// cmds = "logcat -s way";//打印标签过滤信息

cmds = "logcat *:e *:i | grep \"(" + mPID + ")\"";

}

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;

}

}

}

}

}

记得加上权限：

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

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

另外把那个时间的工具类也分享一下：

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package com.way.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

}

}

OK，所有事情做完之后，在我们的应用中start一下就OK了，使用完之后，记得调用一下stop：

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public class GPSApplication extends Application {

@Override

public void onCreate() {

// TODO Auto-generated method stub

LogcatHelper.getInstance(this).start();

}

}