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POHow to invoke a method (reflection) with a not generic parameter?
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  1. POHow to invoke a method (reflection) with a not generic parameter?
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    copied!<p>I have a little problem. I am developing an Android applikation. There you can dynamicly load classes from other applications (packages). First of all, i do not want to "hack" an third-party app, i want to try to build up plugins for my own app. So what do i have?</p> <p>2 Test applications and 1 library which is in both apps included.</p> <p>So the code for app1:</p> <pre><code>package com.ftpsynctest.app1; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.lang.reflect.Type; import android.app.Activity; import android.content.pm.PackageManager.NameNotFoundException; import android.os.Bundle; import com.syncoorp.ftpsyncx.commons.SyncFile; import dalvik.system.PathClassLoader; public class App1Activity extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); SyncFile f = new SyncFile("bla"); String classname = "com.ftpsynctest.app2.classcall"; String classpath = getApk("com.ftpsynctest.app1") + ":" + getApk("com.ftpsynctest.app2"); PathClassLoader myClassLoader = new dalvik.system.PathClassLoader(classpath, ClassLoader.getSystemClassLoader()); try { Class c = Class.forName(classname, true, myClassLoader); for (Method m : c.getDeclaredMethods()) { System.out.println("Method: " + m.getName()); for (Type t : m.getGenericParameterTypes()) { System.out.println(" - type: " + t.toString()); } m.invoke(c.newInstance(), new Object[] { new com.syncoorp.ftpsyncx.commons.SyncFile("bla") }); break; } } catch (ClassNotFoundException e) {e.printStackTrace();} catch (IllegalArgumentException e) {e.printStackTrace();} catch (IllegalAccessException e) {e.printStackTrace();} catch (InvocationTargetException e) {e.printStackTrace();} catch (InstantiationException e) {e.printStackTrace();} } private String getApk(String packageName) { try { return this.getPackageManager().getApplicationInfo(packageName, 0).sourceDir;} catch (NameNotFoundException e) {e.printStackTrace();} return ""; } } </code></pre> <p>So i want to create the class <strong><em>com.ftpsynctest.app2.classcall</em></strong> and call the method <strong><em>modify</em></strong> with a parameter of type <strong><em>com.syncoorp.ftpsyncx.commons.SyncFile</em></strong>.</p> <p>My app2 code:</p> <pre><code>package com.ftpsynctest.app2; import com.syncoorp.ftpsyncx.commons.SyncFile; public class classcall { public SyncFile modify(SyncFile file) { file.change_date = 123; return file; } } </code></pre> <p>I first installed app2 to <strong>provide</strong> the class to app1. After that succeed i started app1.</p> <p>My Output:</p> <p><strong>01-10 22:21:48.804: INFO/System.out(4681): Method: modify<br> 01-10 22:21:48.809: INFO/System.out(4681): - type: class com.syncoorp.ftpsyncx.commons.SyncFile</strong></p> <p>So for now it looks good. the parameter type of the found method is <strong>com.syncoorp.ftpsyncx.commons.SyncFile</strong> and my provided one is the same.</p> <p>But i get the following error:</p> <pre><code> java.lang.IllegalArgumentException: argument type mismatch at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:507) at com.ftpsynctest.app1.App1Activity.onCreate(App1Activity.java:44) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667) at android.app.ActivityThread.access$1500(ActivityThread.java:117) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:130) at android.app.ActivityThread.main(ActivityThread.java:3691) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:507) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:907) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:665) at dalvik.system.NativeStart.main(Native Method) </code></pre> <p>But why? my output tells me that it is SyncFile and i put SyncFile to the invoke command. Whats the problem there? Can it be that compiling app2 creates a class from SyncFile which is different from the compiled app1 ? if yes, why ? the SyncFile class is the same physical class within my "commons" library which both projects share.</p> <p>Anybody has a solution or answer?</p>
 

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