Android Crash日志本地输出到文件

1.说明

当没有firebase 或者 bugly时，crash日志本地存储可以方便的查看并发现问题，系统各个版本存储或有差别，具体路径可参考 此文章

2.具体使用

• 1.创建CrashHandlers实现Thread.UncaughtExceptionHandler，具体代码如下

public class CrashHandlers implements Thread.UncaughtExceptionHandler {

    public static final String TAG = "CrashHandler";

    // 系统默认的UncaughtException处理类
    private Thread.UncaughtExceptionHandler mDefaultHandler;
    // CrashHandler实例
    private static CrashHandlers INSTANCE = new CrashHandlers();
    // 程序的Context对象
    private Context mContext;
    // 用来存储设备信息和异常信息
    private Map infos = new HashMap();

    /**
     * 保证只有一个CrashHandler实例
     */
    private CrashHandlers() {
    }

    /**
     * 获取CrashHandler实例 ,单例模式
     */
    public static CrashHandlers getInstance() {
        return INSTANCE;
    }

    /**
     * 初始化
     *
     * @param context
     */
    public void init(Context context) {
        Log.e("CrashHandler","...........................2");
        mContext = context;
        // 获取系统默认的UncaughtException处理器
        mDefaultHandler = Thread.getDefaultUncaughtExceptionHandler();
        // 设置该CrashHandler为程序的默认处理器
        Thread.setDefaultUncaughtExceptionHandler(this);
    }


    /**
     * 当UncaughtException发生时会转入该函数来处理
     */
    @Override
    public void uncaughtException(Thread thread, Throwable ex) {
        if (!handleException(ex) && mDefaultHandler != null) {
            // 如果用户没有处理则让系统默认的异常处理器来处理
            mDefaultHandler.uncaughtException(thread, ex);
        } else {
            try {
                Thread.sleep(3000);
            } catch (InterruptedException e) {
                Log.e(TAG, "error : ", e);
            }
            // 退出程序
            android.os.Process.killProcess(android.os.Process.myPid());
            System.exit(1);
        }
    }

    /**
     * 自定义错误处理,收集错误信息 发送错误报告等操作均在此完成.
     *
     * @param ex
     * @return true:如果处理了该异常信息;否则返回false.
     */
    private boolean handleException(Throwable ex) {
        if (ex == null) {
            return false;
        }
        // 收集设备参数信息
        collectDeviceInfo(mContext);
        // 保存日志文件
        saveCrashInfo2File(ex);
        return false;
    }

    /**
     * 收集设备参数信息
     *
     * @param ctx
     */
    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 (PackageManager.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);
            }
        }
    }

    /**
     * 保存错误信息到文件中
     *
     * @param ex
     * @return 返回文件名称, 便于将文件传送到服务器
     */
    private String saveCrashInfo2File(Throwable ex) {
        Log.e(TAG,"------1"+ ex.getMessage());
        StringBuffer sb = new StringBuffer();
        Calendar calendar = Calendar.getInstance();
        int year = calendar.get(Calendar.YEAR);
        int month = calendar.get(Calendar.MONTH) + 1;
        int day = calendar.get(Calendar.DAY_OF_MONTH);
        int hour = calendar.get(Calendar.HOUR_OF_DAY);
        int minute = calendar.get(Calendar.MINUTE);
        int second = calendar.get(Calendar.SECOND);
        String time = year + "-" + month + "-" + day + " " + hour + ":" + minute + ":" + second;
        sb.append("\r\n");
        sb.append("\r\n");
        sb.append("\r\n");
        sb.append("************************************************"+time+"****************************************"+"\r\n");
        sb.append("\r\n");
        for (Map.Entry 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 {
            String fileName = "errorLog.txt";
            if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
//                String path = Environment.getExternalStorageDirectory() + "/errorLog";
//手机里的路径为：文件管理器 - Android/data/包名/-cach/errorLog
                String path = mContext.getExternalCacheDir() + "/errorLog";
                Log.e(TAG, "-----2"+path);
                File dir = new File(path);
                if (!dir.exists()) {
                    dir.mkdir();
                }
//                File file = new File(path + File.separator + fileName);
                File file = new File(dir ,File.separator +  System.currentTimeMillis()+fileName);
                if (!file.exists()) {
                    file.createNewFile();
                }
                FileWriter fileWriter = new FileWriter(file, true);
                fileWriter.write(sb.toString());
                Log.e(TAG, "--write===="+path);
                fileWriter.close();
            }
            return fileName;
        } catch (Exception e) {
            Log.e(TAG, "--====="+e.toString());
            return null;
        }
    }
}

• 2.在Application的onCreate()中初始化

  @Override
    public void onCreate() {
        super.onCreate();
        CrashHandlers.getInstance().init(this);
    }