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[操作系统]Android 对程序异常崩溃的捕捉


转载博客:http://blog.csdn.net/i_lovefish/article/details/17719081

以下为异常捕捉处理代码: 

import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStreamReader; 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.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;    /**  * UncaughtException处理类,当程序发生Uncaught异常的时候,有该类来接管程序,并记录发送错误报告.  *  * 需要在Application中注册,为了要在程序启动器就监控整个程序。 */   public class CrashHandler implements 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;   //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() {       if(instance == null)       instance = new CrashHandler();       return instance;     }        /**    * 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);            //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_SHORT).show();           Looper.loop();         }       }.start();       //保存日志文件        saveCatchInfo2File(ex);      return true;     }          /**    * 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 (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 saveCatchInfo2File(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 + ".log";         if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {           String path = "/mnt/sdcard/crash/";           File dir = new File(path);           if (!dir.exists()) {             dir.mkdirs();           }           FileOutputStream fos = new FileOutputStream(path + fileName);           fos.write(sb.toString().getBytes());          //发送给开发人员         sendCrashLog2PM(path+fileName);         fos.close();         }         return fileName;       } catch (Exception e) {         Log.e(TAG, "an error occured while writing file...", e);       }       return null;     }        /**   * 将捕获的导致崩溃的错误信息发送给开发人员   *    * 目前只将log日志保存在sdcard 和输出到LogCat中,并未发送给后台。   */   private void sendCrashLog2PM(String fileName){     if(!new File(fileName).exists()){       Toast.makeText(mContext, "日志文件不存在!", Toast.LENGTH_SHORT).show();       return;     }     FileInputStream fis = null;     BufferedReader reader = null;     String s = null;     try {       fis = new FileInputStream(fileName);       reader = new BufferedReader(new InputStreamReader(fis, "GBK"));       while(true){         s = reader.readLine();         if(s == null) break;         //由于目前尚未确定以何种方式发送,所以先打出log日志。         Log.i("info", s.toString());       }     } catch (FileNotFoundException e) {       e.printStackTrace();     } catch (IOException e) {       e.printStackTrace();     }finally{  // 关闭流       try {         reader.close();         fis.close();       } catch (IOException e) {         e.printStackTrace();       }     }   } }

针对异常的捕捉要进行全局监控整个项目,所以要将其在Application中注册(也就是初始化):

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

现在模拟一个空指针异常:

import android.app.Activity; import android.os.Bundle;  public class CatchExceptionLogActivity extends Activity {   /** Called when the activity is first created. */   private String s;   @Override   public void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.main);     System.out.println(s.equals("hello")); // s没有进行赋值,所以会出现NullPointException异常   } }

别忘了在配置文件中对Application进行注册:

<?package="com.forms.catchlog"   android:versionCode="1"   android:versionName="1.0" >    <uses-sdk android:minSdkVersion="8" />   <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>       <application     android:icon="@drawable/ic_launcher"     android:label="@string/app_name"      <span >android:name=".CrashApplication"></span>     <activity       android:label="@string/app_name"       android:name=".CatchExceptionLogActivity" >       <intent-filter >         <action android:name="android.intent.action.MAIN" />          <category android:name="android.intent.category.LAUNCHER" />       </intent-filter>     </activity>   </application>  </manifest>

添加异常捕获之后的日志提示

由于Android设备各异,第三方定制的Android系统也非常多,我们不可能对所有的设备场景都进行测试,因而开发一款完全无bug的应用几乎是不可能的任务,那么当应用在用户的设备上Force Close时,我们是不是可以捕获这个错误,记录用户的设备信息,然后让用户选择是否反馈这些堆栈信息,通过这种bug反馈方式,我们可以有针对性地对bug进行修复。

当我们的的应用由于运行时异常导致Force Close的时候,可以设置主线程的UncaughtExceptionHandler,实现捕获运行时异常的堆栈信息。同时用户可以把堆栈信息通过发送邮件的方式反馈给我们。下面是实现的代码:

代码下载请按此

例子:点击按钮后,会触发一个NullPointerException的运行时异常,这个例子实现了捕获运行时异常,发送邮件反馈设备和堆栈信息的功能。

界面1(触发运行时异常)

  

界面2(发送堆栈信息)

  

TestActivity.java

package com.zhuozhuo; import java.io.PrintWriter; import java.io.StringWriter; import java.lang.Thread.UncaughtExceptionHandler; import android.app.Activity; import android.content.Intent; import android.net.Uri; import android.os.Build; import android.os.Bundle; import android.util.Log; import android.view.View; import android.view.View.OnClickListener; import android.widget.EditText; import android.widget.TextView; public class TestActivity extends Activity {   /** Called when the activity is first created. */    @Override   public void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.main);     Thread.setDefaultUncaughtExceptionHandler(new UncaughtExceptionHandler() {//给主线程设置一个处理运行时异常的handler        @Override       public void uncaughtException(Thread thread, final Throwable ex) {         StringWriter sw = new StringWriter();         PrintWriter pw = new PrintWriter(sw);         ex.printStackTrace(pw);                 StringBuilder sb = new StringBuilder();                 sb.append("Version code is ");         sb.append(Build.VERSION.SDK_INT + "\n");//设备的Android版本号         sb.append("Model is ");         sb.append(Build.MODEL+"\n");//设备型号         sb.append(sw.toString());         Intent sendIntent = new Intent(Intent.ACTION_SENDTO);         sendIntent.setData(Uri.parse("mailto:csdn@csdn.com"));//发送邮件异常到csdn@csdn.com邮箱         sendIntent.putExtra(Intent.EXTRA_SUBJECT, "bug report");//邮件主题         sendIntent.putExtra(Intent.EXTRA_TEXT, sb.toString());//堆栈信息         startActivity(sendIntent);         finish();       }     });         findViewById(R.id.button).setOnClickListener(new OnClickListener() {             @Override       public void onClick(View v) {         Integer a = null;         a.toString();//触发nullpointer运行时错误                }     });       } } 

main.
<?   android:orientation="vertical" android:layout_width="fill_parent"   android:layout_height="fill_parent">   <TextView android:layout_width="fill_parent"     android:layout_height="wrap_content" android:text="@string/hello" />   <EditText android:id="@+id/editText1" android:layout_width="match_parent"     android:text="点击按钮触发运行时异常" android:layout_height="wrap_content"     android:layout_weight="1" android:gravity="top"></EditText>   <Button android:text="按钮" android:id="@+id/button"     android:layout_width="wrap_content" android:layout_height="wrap_content"     android:layout_gravity="center_horizontal"></Button> </LinearLayout>