1. package com.scott.crash;
2. import android.app.Activity;
3. import android.os.Bundle;
4. public class MainActivity extends Activity {
5. private String s;
6. @Override
7. public void onCreate(Bundle savedInstanceState) {
8. super.onCreate(savedInstanceState);
9. System.out.println(s.equals("any string"));
10. }
11. }

1. <pre name="code" class="java">package com.scott.crash;
   import java.io.File;
   import java.io.FileNotFoundException;
   import java.io.FileOutputStream;
   import java.io.IOException;
   import java.io.PrintWriter;
   import java.io.StringWriter;
   import java.io.Writer;
   import java.lang.Thread.UncaughtExceptionHandler;
   import java.lang.reflect.Field;
   import java.text.DateFormat;
   import java.text.SimpleDateFormat;
   import java.util.Date;
   import java.util.HashMap;
   import java.util.Map;
   import android.content.Context;
   import android.content.Intent;
   import android.content.pm.PackageInfo;
   import android.content.pm.PackageManager;
   import android.content.pm.PackageManager.NameNotFoundException;
   import android.os.Build;
   import android.os.Environment;
   import android.os.Looper;
   import android.util.Log;
   import android.widget.Toast;
   public class CrashHandler implements UncaughtExceptionHandler{private CrashAplication softApp;public static final String TAG="CrashHandler";//系统默认的UncaughtException处理类private Thread.UncaughtExceptionHandler mDefaultHandler;//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**/public  CrashHandler(CrashAplication app){softApp=app;}/*** 初始化*/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为程序默认处理器Thread.setDefaultUncaughtExceptionHandler(this);;}@Overridepublic void uncaughtException(Thread thread, Throwable ex) {Log.e(TAG, "error : ", ex); //收集设备参数信息   collectDeviceInfo(mContext);  //保存日志文件   saveCrashInfo2File(ex);long threadId = thread.getId();          if (threadId != 1) {  // 此处示例跳转到汇报异常界面。  Intent intent = new Intent(softApp, LoginActivity.class);  intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);   softApp.startActivity(intent);  } else {  // 此处示例发生异常后，重新启动应用  Intent intent = new Intent(softApp, LoginActivity.class);    intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);  softApp.startActivity(intent);  // kill App Progress  android.os.Process.killProcess(android.os.Process.myPid());     }}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);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/crash/";File dir=new File(path);if(!dir.exists()){dir.mkdirs();}try {FileOutputStream fos=new FileOutputStream(path + fileName);fos.write(sb.toString().getBytes());} catch (FileNotFoundException e) {// TODO Auto-generated catch blockLog.e(TAG, "an error occured while writing file...", e);  } catch (IOException e) {// TODO Auto-generated catch blockLog.e(TAG, "an error occured while writing file...", e);  }}return null;}private void collectDeviceInfo(Context ctx) {PackageManager pm=ctx.getPackageManager();PackageInfo pi;try {pi = pm.getPackageInfo(ctx.getPackageCodePath(),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) {// TODO Auto-generated catch blockLog.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 (IllegalAccessException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IllegalArgumentException e) {// TODO Auto-generated catch blockLog.e(TAG, "an error occured when collect crash info", e);}}}  }
   

<pre name="code" class="java">package com.scott.crash;
import android.app.Application;public class CrashAplication extends Application{public void onCreate() {  super.onCreate();  CrashHandler crashHandler = new CrashHandler(this);  crashHandler.init(getApplicationContext());  }
}

1. <application android:name=".CrashApplication" ...>
2. </application>

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

1. CPU_ABI=armeabi
2. CPU_ABI2=unknown
3. ID=FRF91
4. MANUFACTURER=unknown
5. BRAND=generic
6. TYPE=eng
7. ......
8. Caused by: java.lang.NullPointerException
9. at com.scott.crash.MainActivity.onCreate(MainActivity.java:13)
10. at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
11. at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
12. ... 11 more