Question

我使用以下代码来捕获全局未捕获的错误，测试代码System.out.println(s.equals("any string"));将导致错误。

在我看来，会创建一个错误日志文件，但事实上，这三个错误日志文件是用相同的内容创建的，我的代码中有什么问题？

顺便说一句，我测试Android 4.0中的代码，只生成了一个错误日志文件！但是当它在Android 5.0下运行时，会生成三个错误日志文件！

MainActivity.java

public class MainActivity extends AppCompatActivity {
    private String s;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        System.out.println(s.equals("any string"));
    }

}

CrashApplication.java

public class CrashApplication extends Application {
    @Override
    public void onCreate() {
        super.onCreate();
        CrashHandler crashHandler = CrashHandler.getInstance();
        crashHandler.init(getApplicationContext());
    }
}

CrashHandler.java

public class CrashHandler implements UncaughtExceptionHandler {

    public static final String TAG = "CrashHandler";   
    private Thread.UncaughtExceptionHandler mDefaultHandler;  
    private static CrashHandler INSTANCE = new CrashHandler();   
    private Context mContext;

    private Map<String, String> infos = new HashMap<String, String>();


    private DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss");


    private CrashHandler() {
    }


    public static synchronized  CrashHandler getInstance() {
        return INSTANCE;
    }


    public void init(Context context) {
        mContext = context;      
        mDefaultHandler = Thread.getDefaultUncaughtExceptionHandler();       
        Thread.setDefaultUncaughtExceptionHandler(this);
    }


    @Override
    public void uncaughtException(Thread thread, Throwable ex) {
        if (!handleException(ex) && mDefaultHandler != null) {

            mDefaultHandler.uncaughtException(thread, ex);
        } else {
            try {
                Thread.sleep(3000);
            } catch (InterruptedException e) {
                Log.e(TAG, "error : ", e);
            }

            android.os.Process.killProcess(android.os.Process.myPid());
            System.exit(1);
        }
    }


    private boolean handleException(Throwable ex) {
        if (ex == null) {
            return false;
        }

        new Thread() {
            @Override
            public void run() {
                Looper.prepare();
                Toast.makeText(mContext, "Sorry.", Toast.LENGTH_LONG).show();
                Looper.loop();
            }
        }.start();

        collectDeviceInfo(mContext);

        saveCrashInfo2File(ex);
        return true;
    }

    public void collectDeviceInfo(Context ctx) {
        try {
            PackageManager pm = ctx.getPackageManager();
            PackageInfo pi = pm.getPackageInfo(ctx.getPackageName(), PackageManager.GET_ACTIVITIES);
            if (pi != null) {
                String versionName = pi.versionName == null ? "null" : pi.versionName;
                String versionCode = pi.versionCode + "";
                infos.put("versionName", versionName);
                infos.put("versionCode", versionCode);
            }
        } catch (NameNotFoundException e) {
            Log.e(TAG, "an error occured when collect package info", e);
        }
        Field[] fields = Build.class.getDeclaredFields();
        for (Field field : fields) {
            try {
                field.setAccessible(true);
                infos.put(field.getName(), field.get(null).toString());
                Log.d(TAG, field.getName() + " : " + field.get(null));
            } catch (Exception e) {
                Log.e(TAG, "an error occured when collect crash info", e);
            }
        }
    }


    private String saveCrashInfo2File(Throwable ex) {

        StringBuffer sb = new StringBuffer();
        for (Map.Entry<String, String> entry : infos.entrySet()) {
            String key = entry.getKey();
            String value = entry.getValue();
            sb.append(key + "=" + value + "\n");
        }

        Writer writer = new StringWriter();
        PrintWriter printWriter = new PrintWriter(writer);
        ex.printStackTrace(printWriter);
        Throwable cause = ex.getCause();
        while (cause != null) {
            cause.printStackTrace(printWriter);
            cause = cause.getCause();
        }
        printWriter.close();
        String result = writer.toString();
        sb.append(result);
        try {
            long timestamp = System.currentTimeMillis();
            String time = formatter.format(new Date());
            String fileName = "crash-" + time + "-" + timestamp + ".txt";
            if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
                String path = Environment.getExternalStorageDirectory() + "/MyCrash/";
                File dir = new File(path);
                if (!dir.exists()) {
                    dir.mkdirs();
                }
                FileOutputStream fos = new FileOutputStream(path + fileName);
                fos.write(sb.toString().getBytes());
                fos.close();
            }
            return fileName;
        } catch (Exception e) {
            Log.e(TAG, "an error occured while writing file...", e);
        }
        return null;
    }
}

Answer 1

android中有不同的日志文件：Error，Debug，Verbose等。因此它们有不同的限定符，它们是Log.e，Log.d，Log.v等。其中两个你使用的是e和d限定符，但我不知道第三个

为什么创建了三个错误日志文件？

1 个答案: