Core Java Interview Questions, Answers for Freshers and Experienced asked in various Company Job Interviews

Core Java Interview Questions

Questions Answers Views Company eMail

Hi Anyone know the model / questions of the Federal bank sample questions for the post of Specialist Officers - Programmers. Please post if anyone have..

2305

How to make a class immutable?

Bosch, TSYS,

15 30590

What is the difference between Abstract Class and Interface

Amdocs,

8 15738

How to perform Singleton of the java class object on multi JVM?

2 12587

How to send a request to garbage collector?

4 8253

How can you say HashMap is syncronized?

Arete, IBM,

14 20943

which pattern is default in scanner package?

Satyam,

2235

what is d difference between deep cloning and shallow cloning in core java?

Satyam,

3 17553

what is the use of private constructor in core java?

OnMobile, Satyam, Yash Technologies,

3 19619

what is the use of datasource in core java?

Satyam,

3 10090

public class AboutStrings{ public static void main(String args[]){ String s1="hello"; String s2="hel"; String s3="lo"; String s4=s2+s3; //to know the hash codes of s1,s4. System.out.println(s1.hashCode()); System.out.println(s4.hashCode()); // these two s1 and s4 are having same hashcodes. if(s1==s4){ System.out.println("s1 and s4 are same."); }else System.out.println("s1 and s4 are not same."); } } Somebody told me that, == operator compares references of the objects. In the above example even though s1 and s4 are refering to same object(having same hash codes), it is printing s1 and s4 are not same. Can anybody explain in detail why it is behaving like this? Thanks in Advance RavuriVinod

TCS,

4 7629

if two references are having same hash codes,is that means those are refering to same object?

CTS,

5 11093

Difference String and String Buffer

4 7420

What is object

6 9229

How to make class immutable

6 10127

Post New Core Java Questions

Un-Answered Questions { Core Java }

Will the compiler creates a default constructor if I have a parameterized constructor in the class?

1113

How can you share data between two thread in Java?

945

Is java an open source?

971

Wha is the output from system.out.println(“hello”+null); ?

1143

Can I use % with real numbers?

1021

What's the default access specifier for variables and methods of a class?

1120

What is the replace tool?

1167

Can I declare class as static or private?

965

How do I run java on windows?

1173

Write a program to print the pattern given below

934

Define an abstract class with reference to java.

997

What is use of map in java?

1011

Which class is used by server applications to obtain a port and listen for client requests?

965

What is widening and narrowing in java? Discuss with an example.

1040

When a lot of changes are required in data, which one should be a preference to be used? String or stringbuffer?

1240

For More Un-Answered { Core Java } Questions Click Here