APP全局异常捕获，并保存本地文件

 public class CrashHandler 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 CrashHandler INSTANCE = new CrashHandler();
     // 程序的Context对象
     private Context mContext;

     //用来存储设备信息和异常信息
     private Map<String, String> infos = new HashMap<String, String>();

     //用于格式化日期,作为日志文件名的一部分
     private DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss");

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

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

     /**
      * 初始化
      * @param context
      */
     public void init(Context context) {
         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) {
         // ToastUtil.show(mContext, ex.getMessage());
         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(500);
             } catch (InterruptedException e) {
                 Log.e(TAG, "error : ", e);
             }
             // 退出程序
             android.os.Process.killProcess(android.os.Process.myPid());
             System.exit(1);
 //            KJActivityStack.create().AppExit(mContext);// 结束整个应用程序
         }
     }

     /**
      * 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;
         }
         // 使用Toast来显示异常信息
         new Thread() {
             @Override
             public void run() {
                 Looper.prepare();
                 Toast.makeText(mContext, "很抱歉,程序出现异常,即将退出.", Toast.LENGTH_LONG).show();
                 Looper.loop();
             }
         }.start();
         //保存日志文件
         String path = saveCrashInfo2File(ex);
         return true;
     }

     /**
      * 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) {
         infos = PhoneUtils.collectDeviceInfo(mContext);
         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);
         FileOutputStream fos = null;
         try {
             long timestamp = System.currentTimeMillis();
             String time = formatter.format(new Date());
             String fileName = "crash-" + time + "-" + timestamp + ".log";
             if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
                 String path = "/sdcard/aaaaaaaaaaaaaaaaaaaaacrash/";
 //                String path = mContext.getCacheDir() + "/crash/";
                 File dir = new File(path);
                 if (!dir.exists()) {
                     dir.mkdirs();
                 }
                 fos = new FileOutputStream(path + fileName);
                 fos.write(sb.toString().getBytes());
             }
             return fileName;
         } catch (Exception e) {
             Log.e(TAG, "an error occured while writing file...", e);
         } finally {
             try {
                 if (fos != null)
                     fos.close();
             } catch (IOException e) {
                 Log.e(TAG, "an error occured while fos.close...", e);
             }
         }
         return null;
     }