Design - Interview Questions and Answers for 'Bank of america india' | Search Interview Question

Design - Interview Questions and Answers for 'Bank of america india' - 2 question(s) found - Order By Newest

Very frequently asked. Usually followed by questions related to private constructor and synchronized access. Frequently asked in JPMorgan and TCS (Based on 2 feedback)

Q1. Explain Singleton Design Pattern ?

Design

Ans. http://www.buggybread.com/2014/03/java-design-pattern-singleton-interview.html

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java design pattern singleton at&t ebay fidelity india united healthcare india Asked in 46 Companies intermediate frequent}

Related Questions

Difference between Static and Singleton Class ?

What is the difference between Singleton and Prototype Bean scope in Spring ?

serialization and deserialization of singleton class

What is the difference between these two approaches of creating singleton Class ?

//Double Checked Locking Code
public static Singleton createInstance() {
   if(singleton == null){
      synchronized(Singleton.class) {
         if(singleton == null) {
            singleton = new Singleton();
         }
      }
   }
   return singleton;
}

//Single checked locking code
public static Singleton createInstance() {
   synchronized(Singleton.class) {
      if(singleton == null) {
         singleton = new Singleton();
      }
   }
   return singleton;
}

What are design situations to use Singleton and Prototype Design Pattern ?

How to avoid cloning, serialization in the singleton class ?

When singleton can break and how to resolve it

If you are given choice to either load object eagerly or lazily , which one would you use in case of singleton pattern ?

When should we use prototype scope and singleton scope for beans ?

Q2. How to make sure that only one instance is created in Singleton Pattern ?

Core Java

Ans. public class SingleTon {
private SingleTon() {
if (singleTon != null) {
throw new RuntimeException("cant not create the object");
}
}
public Object clone() throws CloneNotSupportedException {
throw new CloneNotSupportedException("can not be create");
}

static private volatile SingleTon singleTon;
public static SingleTon getInstance() {
SingleTon singleTon = this.sample;
if (singleTon == null) {
synchronized (this) {
singleTon = this.singleTon;
if (singleTon == null) {
singleTon = this.singleton = new SingleTon();
}
}
}
return singleTon;
}
}