Android--保存logcat到文件

最新推荐文章于 2024-03-19 17:24:09 发布

baihua2001cn

最新推荐文章于 2024-03-19 17:24:09 发布

阅读量997

点赞数

CC 4.0 BY-SA版权

分类专栏： android studio 文章标签： android 安卓

原文链接：https://www.cnblogs.com/qingyoucan/p/3296638.html

android studio 专栏收录该内容

34 篇文章

订阅专栏

本文介绍了一种方法，用于自动保存Android应用运行时的Logcat日志至本地文件，以便于开发者离线分析和定位问题。通过创建一个工具类，可以在应用启动时开始记录日志，并在应用终止时停止记录。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

有时候程序出现异常停止，而logcat 的相关信息很快会被冲掉，因而不能够及时的获取异常信息。所以，借鉴别人的代码，写一个工具类，将相关logcat信息及时的保存到文件。

工具类代码:

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;

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();

}

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 + "/";

}

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 | grep \"(" + mPID + ")\"";//show log of all level

// cmds = "logcat -s way";//Print label filtering information

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((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;

}

然后在相应的application 或 activity中加入如下代码：

private void startLogcatManager() {
        String folderPath = null;
        
        if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {// save in SD card first 
            folderPath = Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator + "BDT-Logcat";
        } else {// If the SD card does not exist, save in the directory of application.
 
            folderPath = this.getFilesDir().getAbsolutePath() + File.separator + "BDT-Logcat";  
        }
        
        LogcatFileManager.getInstance().start(folderPath);  
    } 
    
    private void stopLogcatManager() {

        LogcatFileManager.getInstance().stop(); 
    }

在对应application 或 activity 对应onCreate()方法及onTerminate()调用对应接口，代码如下：

@Override
    public void onCreate() {
        super.onCreate();
        startLogcatManager();
}


@Override
    public void onTerminate() {
                stopLogcatManager();
                super.onTerminate();
}