通过在 Android 中实现 Proguard 在使用 JDBC 的 Asynctask 中应用程序崩溃
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【中文标题】通过在 Android 中实现 Proguard 在使用 JDBC 的 Asynctask 中应用程序崩溃【英文标题】：App crash in Asynctask with JDBC by Implementing Proguard in Android 【发布时间】：2017-12-18 12:56:17 【问题描述】：我的应用程序之前运行良好，但在我的项目中启用 ProGuard 后，应用程序在“发布”和“调试”apk 中立即崩溃。我也禁用了proguard，然后再试一次，它可以工作。
现在我的问题是如何在我的项目中使用 jdbc 以及 proguard，可以吗？
这是我的调试内容
E/androidRuntime: FATAL EXCEPTION: AsyncTask #1
Process: com.example.aileen.rotaractclub, PID: 6131
java.lang.RuntimeException: An error occurred while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:309)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:354)
at java.util.concurrent.FutureTask.setException(FutureTask.java:223)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.ExceptionInInitializerError
at com.b.a.bq.connect(Unknown Source)
at java.sql.DriverManager.getConnection(DriverManager.java:179)
at java.sql.DriverManager.getConnection(DriverManager.java:213)
at com.example.aileen.rotaractclub.b.a.a(Unknown Source)
at com.example.aileen.rotaractclub.b.a$c.a(Unknown Source)
at com.example.aileen.rotaractclub.b.a$c.doInBackground(Unknown Source)
at android.os.AsyncTask$2.call(AsyncTask.java:295)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.RuntimeException: java.lang.NoSuchMethodException: <init> [class java.lang.String, int, class java.util.Properties, class java.lang.String, class java.lang.String]
at com.b.a.o.<clinit>(Unknown Source)
at com.b.a.bq.connect(Unknown Source)
at java.sql.DriverManager.getConnection(DriverManager.java:179)
at java.sql.DriverManager.getConnection(DriverManager.java:213)
at com.example.aileen.rotaractclub.b.a.a(Unknown Source)
at com.example.aileen.rotaractclub.b.a$c.a(Unknown Source)
at com.example.aileen.rotaractclub.b.a$c.doInBackground(Unknown Source)
at android.os.AsyncTask$2.call(AsyncTask.java:295)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.NoSuchMethodException: <init> [class java.lang.String, int, class java.util.Properties, class java.lang.String, class java.lang.String]
at java.lang.Class.getConstructor(Class.java:528)
at java.lang.Class.getConstructor(Class.java:492)
at com.b.a.o.<clinit>(Unknown Source)
at com.b.a.bq.connect(Unknown Source)
at java.sql.DriverManager.getConnection(DriverManager.java:179)
at java.sql.DriverManager.getConnection(DriverManager.java:213)
at com.example.aileen.rotaractclub.b.a.a(Unknown Source)
at com.example.aileen.rotaractclub.b.a$c.a(Unknown Source)
at com.example.aileen.rotaractclub.b.a$c.doInBackground(Unknown Source)
at android.os.AsyncTask$2.call(AsyncTask.java:295)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
这是我的异步任务
//Deleting Announcement
public class deleting extends AsyncTask<String,String,String>
Boolean Connection = false;
Boolean isSuccess = false;
ProgressDialog progress;
String title;
String ids;
public deleting(String aydi,String titulo)
ids=aydi;
title =titulo;
@Override
protected void onPreExecute()
super.onPreExecute();
progress = new ProgressDialog(getActivity());
progress.setTitle("Synchronizing");
progress.setMessage("Removing '"+ title +"'\n announcement please wait...");
progress.setIndeterminate(false);
progress.setProgressStyle(android.R.style.Widget_ProgressBar_Small);
progress.show();
progress.setCancelable(false);
@Override
protected String doInBackground(String... params)
try
try
connection = connectionclass(secured_Pref.getString("server",""), secured_Pref.getString("user",""), secured_Pref.getString("pass",""));
if (connection == null)
Connection = false;
else
Connection = true;
PreparedStatement statement = connection.prepareStatement("DELETE FROM Announcements WHERE ID='"+this.ids.toString()+"' AND Title='"+this.title.toString()+"'");
long i =statement.executeUpdate();
try
if (i>0)
isSuccess = true;
else
isSuccess = false;
connection.close();
catch (Exception x)
Toast.makeText(getActivity(), "Error Occur.", Toast.LENGTH_SHORT).show();
catch (Exception e)
e.printStackTrace();
Toast.makeText(getActivity(), "Error Occur.", Toast.LENGTH_SHORT).show();
catch (Exception ex)
isSuccess = false;
return null;
@Override
protected void onPostExecute(String r)
super.onPostExecute(r);
if (Connection)
Toast.makeText(getActivity(),"Successfully Connected.",Toast.LENGTH_LONG).show();
else if(Connection==false)
Toast.makeText(getActivity(),"No Internet Connection.",Toast.LENGTH_LONG).show();
if (isSuccess)
Snackbar.make(getView(), "Announcement is Successfully Removed.", Snackbar.LENGTH_LONG).show();
//Refresh my fragment
FragmentTransaction refresh = getFragmentManager().beginTransaction();
refresh.detach(ViewAnnounce.this).attach(ViewAnnounce.this).commit();
else
Snackbar.make(getView(), "Oops! Error Occur.", Snackbar.LENGTH_LONG).show();
progress.dismiss();
ProGuard 规则
-ignorewarnings
# Basic ProGuard rules for Firebase Android SDK 2.0.0+
-keep class com.firebase.** *;
-keep class org.apache.** *;
-keepnames class com.fasterxml.jackson.** *;
-keepnames class javax.servlet.** *;
-keepnames class org.ietf.jgss.** *;
-dontwarn org.apache.**
-dontwarn org.w3c.dom.**
-renamesourcefileattribute SourceFile
-keep public class * extends android.app.Application
-optimizationpasses 5
-keepattributes *Annotation*,EnclosingMethod
在我的 Gradle 中
buildTypes
release
minifyEnabled true
shrinkResources true
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
debug
debuggable true
minifyEnabled true
shrinkResources true
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
【问题讨论】：
这是我的连接尝试 Class.forName("com.mysql.jdbc.Driver");连接 = DriverManager.getConnection(url, 用户, 密码); catch (SQLException se) Log.e("error here 1 : ", se.getMessage()); catch (ClassNotFoundException e) Log.e("error here 2 : ", e.getMessage()); catch (Exception e) Log.e("error here 3 : ", e.getMessage()); 忘记包含抱歉，Connection connection = null; 【参考方案1】：已通过将此规则包含在我的 proguard 中修复
-dontshrink
【讨论】：
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