Solved

Java question regarding abstract method implementation

Posted on 2011-03-20
6
488 Views
Last Modified: 2012-06-21
Hi experts,

I was referring some open source java code of android. In one of the classes, I saw a method call to another class. The method called was an abstract method inside an abstract class. As is expected, the abstract method do not have any implementation. But, to my wonder, this abstract method returns a List. I do not know, without having any implementation(and return statement) for a method, how this method returns a List?

Please refer the code attached.

Any help in this regard would be appreciated.

Best Regards,
Sreejith
// Calling Method

final List<ResolveInfo> apps = manager.queryIntentActivities(mainIntent, 0);

//Called Method inside another abstract class

public abstract List<ResolveInfo> queryIntentActivities(Intent intent,
            int flags);

Open in new window

0
Comment
Question by:Sreejith22
  • 3
  • 2
6 Comments
 
LVL 92

Accepted Solution

by:
objects earned 250 total points
ID: 35178480
The implementation would be in a subclass of the abstract class
0
 
LVL 92

Assisted Solution

by:objects
objects earned 250 total points
ID: 35178482
though you shouldn't generally need to see the implementation

http://download.oracle.com/javase/tutorial/java/IandI/abstract.html
0
 

Author Comment

by:Sreejith22
ID: 35179350
Hi Objects,

Thanks for your reply. I found out the sub class  of this abstract class which has this method. When I provided a log inside this method, I found out that, this method is being called 5 times, while I was just expecting a single call.

Is there any method by which, I can identify the class(or method), from which this method is called, by providing a log inside called method?
0
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
LVL 92

Assisted Solution

by:objects
objects earned 250 total points
ID: 35179407
0
 
LVL 4

Expert Comment

by:msk_apk
ID: 35180092
when you call ,

final List<ResolveInfo> apps = manager.queryIntentActivities(mainIntent, 0);

manager must be pointing to the object in which the method queryIntentActivities is implemented.
0
 

Author Closing Comment

by:Sreejith22
ID: 35204462
Thanks objects!
0

Featured Post

Forrester Webinar: xMatters Delivers 261% ROI

Guest speaker Dean Davison, Forrester Principal Consultant, explains how a Fortune 500 communication company using xMatters found these results: Achieved a 261% ROI, Experienced $753,280 in net present value benefits over 3 years and Reduced MTTR by 91% for tier 1 incidents.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
program arguments vs VM arguments 4 26
Backup Android 2.3.6 Alarms 15 49
IBM TS2900 (3572) Tape Autoloader Java? 12 58
Samsung Dex 3 43
Displaying an arrayList in a listView using the default adapter is rarely the best solution. To get full control of your display data, and to be able to refresh it after editing, requires the use of a custom adapter.
In this post we will learn how to make Android Gesture Tutorial and give different functionality whenever a user Touch or Scroll android screen.
Viewers will learn about if statements in Java and their use The if statement: The condition required to create an if statement: Variations of if statements: An example using if statements:
This tutorial will introduce the viewer to VisualVM for the Java platform application. This video explains an example program and covers the Overview, Monitor, and Heap Dump tabs.

762 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question