No, this keyword cannot be assigned with null value.

Static methods Static methods symbolize the behavior of entire class. An instance of a class just isn’t required to execute static methods. They are often called using class name. Syntax: ClassName.methodNameClassName.methodName Example class DisplayTest { public static void display(){ System.out.println("Hello World"); } } public class StaticMethodExample { public static void main(String args[]){ DisplayTest.display(); } }class … Read more

Static data members Data members declared with static keyword are generally known as static data members. These are primarily used to characterize these properties that are common to each object. On the time of class loading a single copy is created for static data members and it will be shared by all objects. Memory division … Read more

package com.w3schools;   import java.io.IOException;   public class Test { public static void main(String args[]){ try { Runtime.getRuntime().exec("notepad.exe"); } catch (IOException e) { e.printStackTrace(); } } }package com.w3schools; import java.io.IOException; public class Test { public static void main(String args[]){ try { Runtime.getRuntime().exec("notepad.exe"); } catch (IOException e) { e.printStackTrace(); } } }

Yes, a constructor can be called by another constructor in java. We can use this() to call same class constructor and super() to call super class constructor. class SuperClass{ public SuperClass(int i){ System.out.println("Super class constructor"); } }   class SubClass extends SuperClass { public SubClass(){ //Calling same class constructor this(50); }   public SubClass(int i){ … Read more

No, we cannot use this() and super() in a method in java.

We can create private constructor in java. It is used to restrict the instantiation of a class. We cannot create an object outside of the class, if we create the private constructor. It is used to implement Singleton pattern. The main purpose of singleton pattern is to control object creation i.e. keep only one instance … Read more

As we discussed in previous questions that we can overload a constructor so if we keep return type for a constructor it will be treated as a normal method. Note: Compiler gives a warning message that method has a constructor name. Example public class Main { String Main(){ System.out.println("Hello World"); return "Hello w3schools.com"; } public … Read more

No, we cannot call subclass constructor from superclass constructor. Example class SuperClass{ SuperClass(){ System.out.println("SuperClass constructor"); SubClass(); } } public class SubClass extends SuperClass { SubClass (){ System.out.println("Subclass constructor"); } public static void main(String[] args) { System.out.println("Constructor test"); } }class SuperClass{ SuperClass(){ System.out.println("SuperClass constructor"); SubClass(); } } public class SubClass extends SuperClass { SubClass (){ System.out.println("Subclass … Read more

Parameterized constructor A constructor with one or more parameters is called as parameterized constructor. Why parameterized constructor is used? Parameterized constructor is used to provide the initial values to the object properties (initial state of object). By use of parameterized constructor different objects can be initialize with different data member values or states. Example /** … Read more