Android: Clear cache programmatically [duplicate]

Question

How to clear the cache of every application in my android phone programmmatically? does the clearing of cache programmatically is allowed in android? if allowed, how? I already try to researched it and I can't find the answer that I need

Answer 1

I've found this one:

import java.io.File;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;

public class HelloWorld extends Activity {

   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle *) {
      super.onCreate(*);
      setContentView(R.layout.main);
   }

   @Override
   protected void onStop(){
      super.onStop();
   }

   //Fires after the OnStop() state
   @Override
   protected void onDestroy() {
      super.onDestroy();
      try {
         trimCache(this);
      } catch (Exception e) {
         // TODO Auto-generated catch block
         e.printStackTrace();
      }
   }

   public static void trimCache(Context context) {
      try {
         File dir = context.getCacheDir();
         if (dir != null && dir.isDirectory()) {
            deleteDir(dir);
         }
      } catch (Exception e) {
         // TODO: handle exception
      }
   }

   public static boolean deleteDir(File dir) {
      if (dir != null && dir.isDirectory()) {
         String[] children = dir.list();
         for (int i = 0; i < children.length; i++) {
            boolean success = deleteDir(new File(dir, children[i]));
            if (!success) {
               return false;
            }
         }
      }

      // The directory is now empty so delete it
      return dir.delete();
   }

}

It may be helpful to you.

Answer 2

This is a funny scenario. In the Manifest.Permission documentation

public static final String CLEAR_APP_CACHE

Added in API level 1 Allows an application to clear the caches of all installed applications on the device.

Constant Value: "android.permission.CLEAR_APP_CACHE"

So you can get the permission to clear cache of all application. But I don't think there is any method in the SDK to use this permission. So you can just hold the permission and do nothing with it. Strange from google.

EDIT : This google discussion might be of interest. Dianne Hackborn specifically says that the above permission shouldn't be present in the SDK, since the API to use it is not there.