Android中保存Logcat信息到文件

首先要聲明權限：<uses-permission Android:name="android.permission.READ_LOGS" />

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

實現工具類LogcatFileManager，代碼如下：

package com.fangdd.maiyunmanager.logutil;

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 java.text.SimpleDateFormat;
import java.util.Date;

import android.content.Context;
import android.os.Environment;

public class LogcatFileManager
{
private static LogcatFileManager INSTANCE = null;
private static String PATH_LOGCAT;
private LogDumper mLogDumper = null;
private int mPId;
private SimpleDateFormat simpleDateFormat1 = new SimpleDateFormat("yyyyMMdd");
private SimpleDateFormat simpleDateFormat2 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

public static LogcatFileManager getInstance()
{
if (INSTANCE == null)
{
INSTANCE = new LogcatFileManager();
}
return INSTANCE;
}

private LogcatFileManager()
{
mPId = android.os.Process.myPid();
}

public void startLogcatManager(Context context)
{
String folderPath = null;
if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED))
{
folderPath = Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator + "MMF-Logcat";
}
else
{
folderPath = context.getFilesDir().getAbsolutePath() + File.separator + "MMF-Logcat";
}
LogcatFileManager.getInstance().start(folderPath);
}

public void stopLogcatManager()
{
LogcatFileManager.getInstance().stop();
}

private void setFolderPath(String folderPath)
{
File folder = new File(folderPath);
if (!folder.exists())
{
folder.mkdirs();
}
if (!folder.isDirectory())
{
throw new IllegalArgumentException("The logcat folder path is not a directory: " + folderPath);
}

PATH_LOGCAT = folderPath.endsWith("/") ? folderPath : folderPath + "/";
LogUtils.d(PATH_LOGCAT);
}

public void start(String saveDirectoy)
{
setFolderPath(saveDirectoy);
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, "logcat-" + simpleDateFormat1.format(new Date()) + ".log"), true);
}
catch (FileNotFoundException e)
{
e.printStackTrace();
}

/**
* * * log level：*:v , *:d , *:w , *:e , *:f , *:s * * Show the
* current mPID process level of E and W log. * *
*/
// cmds = "logcat *:e *:w | grep \"(" + mPID + ")\"";
cmds = "logcat *:e *:w | 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((simpleDateFormat2.format(new Date()) + " " + 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;
}
}
}

}
}

然後在應用啟動和退出時關閉管理器就行

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Ubuntu 14.04 x64配置Android 4.4 kitkat編譯環境的方法 http://www.linuxidc.com/Linux/2014-05/101148.htm

Ubuntu 12.04搭建Android開發環境 http://www.linuxidc.com/Linux/2012-09/69961.htm

Ubuntu 14.04 配置 Android SDK 開發環境 http://www.linuxidc.com/Linux/2014-05/101039.htm

64位Ubuntu 11.10下Android開發環境的搭建(JDK+Eclipse+ADT+Android SDK詳細) http://www.linuxidc.com/Linux/2013-06/85303.htm

Ubuntu 12.10 x64 安裝 Android SDK http://www.linuxidc.com/Linux/2013-03/82005.htm

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更多Android相關信息見Android 專題頁面 http://www.linuxidc.com/topicnews.aspx?tid=11