Understanding basic Java-specific interverview questions

Question

Last day I faced an interview and they asked me java questions among which for some questions I didn't know the answer. I am curious to know the answer for that question. Interviewer did not tell me the answer. I am asking that questions here:

• Does Java provide any construct to find out the size of an object?
• Give a simplest way to find out the time a method takes for execution without using any profiling tool?
• What are checked exceptions and runtime exceptions?
• If I write return at the end of the try block, will the finally block still execute?
• If I write System.exit (0); at the end of the try block, will the finally block still execute?

Want to know answers of above question so that it can help me next time.

Explanations, notes, and/or relevant links to the specification would be greatly appreciated over just the simple answers -- and what is a good way to learn this stuff?

Answer 1

I think that all of these can be answered by searching for existing Stack Overflow questions. The reason I think it's worth answering this question with links to previous answers is that you've asked about a lot of different issues, each one of which is interesting in its own right. It's not so likely you'll get an in-depth discussion of these when asking about them all together, but in the answers and comments on previous questions here you'll find a lot of detail and discussion which (a) may be interesting and (b) may help in further interviews. (There may well be better choices - these are just the first reasonable SO answers I found.)

Does Java provide any construct to find out the size of an object?

• In Java, what is the best way to determine the size of an object?
• sizeof java object

Give a simplest way to find out the time a method takes for execution without using any profiling tool?

• How do I time a method's execution in Java?

What are checked exceptions and runtime exceptions?

• Differences between Runtime/Checked/Unchecked/Error/Exception

If I write return at the end of the try block, will the finally block still execute?

• Does finally always execute in Java?

If I write System.exit (0); at the end of the try block, will the finally block still execute?

• How does Java's System.exit() work with try/catch/finally blocks?