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POJava reflection method invoking error
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copied!<p>I'm making a kind of test program to be able to override methods in classes for an api I'm making in java but I'm getting a weird error when trying to invoke a method from another class...</p> <p>Here is the main "component class":</p> <pre><code> package st.cmp; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.util.ArrayList; import java.util.HashMap; import java.util.List; public class Component { public class Overrider{ Class<?> source; Class<?>[] overs; String name; public Overrider(Class<?> s,String n,Class<?>[] o){ source=s; overs=o; name=n; } public Object call(Object[] param){ try { return source.getMethod(name, overs).invoke(this, param); } catch (NoSuchMethodException | SecurityException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IllegalAccessException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IllegalArgumentException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (InvocationTargetException e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } }; public HashMap<String,Component> cmps; public HashMap<String,Overrider> over; public Component(){ cmps=new HashMap<String,Component>(); over=new HashMap<String, Overrider>(); } public void registerComponent(String nm,Component cm){ cmps.put(nm,cm); } public Component getComponent(String nm){ return cmps.get(nm); } public void override(Class<?> cl,String name,Class<?>[] param){ over.put(name,new Overrider(cl,name,param)); } public Object call(String mnm,Object[] a){ Overrider ov=over.get(mnm); if(ov!=null){ ov.call(a); } Class<?>[] abc=new Class<?>[a.length]; for(int i=0;i<a.length;i++){ abc[i]=a[i].getClass(); } try { return this.getClass().getDeclaredMethod(mnm, abc).invoke(this,a); } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException | NoSuchMethodException | SecurityException e) { // TODO Auto-generated catch block try { this.getClass().getDeclaredMethod(mnm, abc).invoke(this,a); } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException | NoSuchMethodException | SecurityException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } } return null; } public void test(String a){ System.out.print(a); } public int add(Integer a,Integer b){ return a+b; } } </code></pre> <p>And this is the main class:</p> <pre><code>package st; import st.cmp.Component; public class Start { public static void main(String[] args) { new Start().start(); } public void start(){ Component a=new Component(); a.call("test",new Object[]{a.call("add",new Object[]{1,5}).toString()}); a.override(this.getClass(), "add", new Class<?>[]{Integer.class,Integer.class}); a.call("test",new Object[]{a.call("add",new Object[]{1,5}).toString()}); } public int add(Integer a,Integer b){ return a*b; } } </code></pre> <p>I'm getting this error when I start the program:</p> <pre><code>6java.lang.IllegalArgumentException: object is not an instance of declaring class at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at st.cmp.Component$Overrider.call(Component.java:22) at st.cmp.Component.call(Component.java:64) at st.Start.start(Start.java:16) at st.Start.main(Start.java:8) 6 </code></pre> <p>Can anyone help me?</p> <p>it says "object is not an instance of declaring class"... But what "object" is it refering to?</p>

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