Databases
StackOverflow2013
Postsdbo
POInvoke an abstract method by reflection
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POInvoke an abstract method by reflection
    primarykey
    data
    text
    <p>I have a class <code>SomeTaskManager</code> with an abstract method <code>runATask</code>. I want to execute the <code>runATask</code> method via reflection, this is my code : what am I missing?</p> <pre><code>SomeTaskManager pm= (SomeTaskManager)context.getSomeTaskManager(); Class c = Class.forName( pm.getClass().getName() ); Method[] allMethods = c.getDeclaredMethods(); for (Method m : allMethods) { if (!m.getName().equals("runATask")) { continue; } m.invoke( c ,new Object[] { someParam, null, 1}); break; } </code></pre> <p>I'm getting this errors</p> <pre><code>java.lang.IllegalArgumentException: object is not an instance of the class at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:507) at de.vogella.android.downloadmanager.DownloadManagerActivity.riflesso(DownloadManagerActivity.java:250) at de.vogella.android.downloadmanager.DownloadManagerActivity.onCreate(DownloadManagerActivity.java:68) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1722) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1784) at android.app.ActivityThread.access$1500(ActivityThread.java:123) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:939) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:130) at android.app.ActivityThread.main(ActivityThread.java:3835) 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:847) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:605) </code></pre>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USZorb
    1. USZorb
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. COWhat's the problem?
      singulars
      1. POInvoke an abstract method by reflection
      1. USIsmail Badawi
    2. COErm, you can't execute an abstract method - there's nothing to execute.
      singulars
      1. POInvoke an abstract method by reflection
      1. USBrian Roach
    3. COYou can if the method is implemented in a subclass, and an instance of that subclass is being used after being instantiated. Anyway, you need to show us the stack trace. We don't know what arguments the method needs, or the types of the arguments you're passing. Also, your loop should process the code on finding the "runATask" method then break, not skip over the ones that aren't that. That's a huge code smell.
      singulars
      1. POInvoke an abstract method by reflection
      1. USChris Dennett
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload