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:
<?xml version="1.0" encoding="utf-8"?>添加异常捕获之后的日志提示
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
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 style="color:#ff0000;">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>
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.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
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>