Data Bank | Yazilim Ders

Why We Cannot Create a Generic Array in Java ?

Java does not allow creation of array with generics as elements. ..

Why ListIterator Has add Method But Iterator Does Not Have in Java ?

ListIterator can iterate in the both directions of a Collection. It maintains two pointer for previous and next element...

240 Java

What is a WeakHashMap in Java ?

WeakHashMap is a class similar to IdentityHashMap. Internally, it is represented by a Hashtable...

211 Java

What is the Main Benefit of IOC Principle in Java ?

Inversion of Control (IOC) principle is the base of Spring framework. It supports dependency injection in an application...

237 Java

How Can You Determine If Your Program Has a Deadlock in Java ?

If we suspect that our application is stuck due to a Deadlock, then we just take a thread dump by using the command specific...

197 Java

Why an Object Used as Key in HashMap Should Be Immutable in Java ?

The Key object should be immutable so that hashCode() method always return the same value for that object...

201 Java

How Will You Make an Object Immutable in Java ?

To make an object immutable follow these two rules. One, do not use any setter methods that can change the fields...

196 Java

Why Should You Define a Default Constructor in Java ?

In general, Java provides a default constructor with each class. But there are certain cases when we want to...

210 Java

Why Does Java Provide Default Constructor ?

In Java all the interaction takes place between Object instances. To create an Object instance, JVM needs...

193 Java

What is Information Hiding in Java ?

Information hiding is OOPS concept. In Java you can use encapsulation to do Information hiding. An object...

254 Java

What is the Reason to Organize Classes and Interfaces in a Package in Java ?

As the name suggests, a package contains a collection of classes. It helps in setting the category of a file...

188 Java

Why Do You Use Upcasting or Downcasting in Java ?

When we want to cast a Sub class to Super class, we use Upcasting. It is also known as widening. Upcasting is always allowed in Java...

214 Java

What is the Difference Between a Class and an Object in Java ?

A Class is a template or a blue print of an Object to be created. An Object is an instance of a Class. A Class...

190 Java

What are the Rules of Method Overloading and Method Overriding in Java ?

When we want to overload a method, we need to make sure that the method name remains same. But method...

201 Java

What is the Use of Run Time Polymorphism in Java ?

During the run time the behavior of an Object can change based on its run time state. Due to this run time...

209 Java

Why String Class is Immutable or Final in Java ?

Since String objects are cached in a String pool, it makes sense to make the String immutable. The cached String...

195 Java

Why Java Does Not Support Operator Overloading ?

Java supports Method overloading but does not support operator overloading. It would make the design more...

221 Java

Why Do We Use JSP Instead of Servlet in Java ?

Since JSP pages are dynamically compiled into servlets, the programmers can easily make updates to the presentation layer code...

207 Java

What is the Difference Between a Cookie and a Session Object in Java ?

Both Cookie and Session are used during communication between Client and Server. The Client can disable...

191 Java

When Do You Use Exception or Error in Java ?

Throwable class is the superclass of Exception and Error classes in Java...