{"id":1214,"date":"2021-10-23T17:24:35","date_gmt":"2021-10-23T17:24:35","guid":{"rendered":"https:\/\/rahulshettyacademy.com\/blog\/index.php\/2021\/10\/23\/sdet-interview-questions-part-1\/"},"modified":"2021-10-23T17:24:35","modified_gmt":"2021-10-23T17:24:35","slug":"sdet-interview-questions-part-1","status":"publish","type":"post","link":"https:\/\/rahulshettyacademy.com\/blog\/index.php\/2021\/10\/23\/sdet-interview-questions-part-1\/","title":{"rendered":"Top SDET Interview Questions in Java – Part 1"},"content":{"rendered":"

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This<\/a> is Part 1 in the series of SDET Interview questions and answers in Java<\/h3>\n<\/div>\n
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table of contents<\/div>\n<\/p><\/div>\n<\/div>\n<\/div>\n
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This is Part 1 in the series of SDET Interview questions and answers in Java<\/a><\/div>\n
1. What is the difference between JDK, JRE, and JVM?<\/a><\/div>\n
2. What are the different types of constructors in Java? And How to overload Constructor?<\/a><\/div>\n
3. What is the static keyword? How it can be used?<\/a><\/div>\n
4. What is this final keyword? how I can be used?<\/a><\/div>\n
5. What is the difference between method overloading and method overriding?<\/a><\/div>\n
6. Could you explain IS-A and HAS-A relationship?<\/a><\/div>\n
7. Explain this and super keyword<\/a><\/div>\n
8. How to check instance of Specified type? Explain with example<\/a><\/div>\n
9. What is a package in Java? What are different types of packages? Can we create a custom package?<\/a><\/div>\n
10. What is run time polymorphism in Java?<\/a><\/div>\n
11. What is the difference between static and dynamic binding in java?<\/a><\/div>\n<\/div>\n
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1. What is the difference between JDK, JRE, and JVM?<\/a><\/h3>\n
JDK<\/strong> is Java Development Kit it is used for Developing Java Application<\/p>\n
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JRE<\/strong> is Java Runtime Environment that is used for running java programs\/application<\/p>\n
JVM<\/strong> is Java Virtual Machine that provides a Platform Independent execution environment for running your code.<\/p>\n
2. What are the different types of constructors in Java? And How to overload Constructor?<\/a><\/h3>\n
Constructor<\/strong> is a block of code, which will have a name as the Class name. The constructor will be executed when a new instance of the class is created.<\/p>\n
There are two types of Constructor<\/strong><\/p>\n
Default Constructor<\/strong><\/em><\/p>\n
Default constructor will not have any parameter, If you don\u2019t define it then compiles creates one automatically. Default constructor will be called by compiler if there is no other constructor.<\/p>\n
Example Code Snippet<\/span><\/span><\/p>\n<\/div>\n
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class Academy {<\/span><\/p>\n
\u00a0\u00a0\u00a0 \/\/ Constructor<\/span><\/p>\n
\u00a0\u00a0\u00a0 Academy() {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“Constructor called”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n
public class SampleClass {<\/span><\/p>\n
\u00a0\u00a0\u00a0 public static void main(String args[]) {<\/span><\/p>\n
\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\/\/ this invokes default constructor.<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Academy academy = new Academy();<\/span><\/p>\n
}\u00a0\u00a0<\/span><\/p>\n
}<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0<\/span><\/p>\n
Output:<\/span><\/span><\/strong><\/p>\n
Constructor called<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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Parameterized Constructor<\/strong><\/p>\n
The parameterized constructor will have parameters, this is mainly used for initialization purposes. You can pass different values to a parameterized constructor at the time of object creation, but values should match the constructor signature<\/p>\n
Example Code Snippet<\/span><\/p>\n<\/div>\n
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\u00a0 \u00a0 class Academy {<\/span><\/p>\n
\u00a0\u00a0\u00a0 int a=0;<\/span><\/p>\n
\u00a0\u00a0\u00a0 int b=0;<\/span><\/p>\n
\u00a0\u00a0\u00a0 \/\/ Parameterized Constructor<\/span><\/p>\n
\u00a0\u00a0\u00a0 Academy(int a, int b) {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“Constructor called”);<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“Addition of “+a+” and “+b+” = “+(a+b));<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n
public class SampleClass {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 public static void main(String args[]) {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \/\/ this invokes default constructor.<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Academy academy = new Academy(10,20);<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n
Output:<\/span><\/strong><\/span><\/p>\n
Constructor called<\/span><\/p>\n
Addition of 10 and 20 = 30<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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3. What is the static keyword? How it can be used?<\/a><\/h3>\n
The static indicates that the particular member belongs to a type itself, rather than to an instance of that type. That means a static member of the class can be accessed before creating any object for that class.<\/p>\n
Static keywords can be used for<\/p>\n
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Variable, also called static fields or Class Variables<\/li>\n
Method<\/li>\n
Block<\/li>\n
Nested Class<\/li>\n<\/ul>\n
Static Variable or Static Fields:<\/strong><\/p>\n
When you prefix fields or variables with static which is called a static variable. When you create the static variable single copy of that variable is created and shared among all instances of an object.<\/p>\n
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The static variable associated with the class can be accessed directly using the class name. The object reference is not needed.<\/li>\n
Static variables are created at the class level.<\/li>\n<\/ul>\n
Example Code Snippet<\/strong><\/p>\n<\/div>\n
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public class SampleClass{<\/span><\/p>\n
\u00a0\u00a0\u00a0 \/\/Example of static variable<\/span><\/p>\n
\u00a0\u00a0\u00a0 public static int exampleVariable =10;<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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Static method<\/strong><\/p>\n
When you create a method and prefix with a static keyword it becomes static methods, static methods belong to the class, not to any object.<\/p>\n
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The static method can be accessed using class name no need for any object reference. The main method is the example of a static method which is commonly used<\/li>\n
A static method cannot be overridden<\/li>\n
You cannot create abstract method using static keyword<\/li>\n
this or super keyword cannot be used for static methods<\/li>\n<\/ul>\n
Example Code Snippet<\/strong><\/p>\n<\/div>\n
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public class SampleClass{<\/span><\/p>\n
\u00a0\u00a0\u00a0 public static void sampleMethod(String name) {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(name);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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Static Block<\/strong><\/p>\n
A block of code which is used with static keyword is known as static block. Static block is mainly used for initializing static variables. You can have multiple static block inside single class. Static block will be executed before main method<\/p>\n
Example Code Snippet<\/strong><\/p>\n<\/div>\n
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public class SampleClass{<\/span><\/p>\n
\u00a0\u00a0\u00a0 public static List<String> fruits = new LinkedList<>();<\/span><\/p>\n
\u00a0\u00a0\u00a0 static {<\/span><\/p>\n
\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0 fruits.add(“Apple”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0 fruits.add(“Banana”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0 fruits.add(“Kiwi”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
\u00a0\u00a0\u00a0<\/span><\/p>\n
\u00a0\u00a0\u00a0 public static void main(String args[]) {<\/span><\/p>\n
\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(SampleClass.fruits.get(0));<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n
Output: Apple<\/span><\/strong><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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Static Class<\/strong><\/p>\n
When you create a class inside another class it is called a nested class, static class only be created as a nested class. Members of the static class can be directly accessed using the outer class.<\/p>\n
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A static class cannot access non-static members of the Outer class<\/li>\n
Static class members can be called with outer class reference<\/li>\n
Static classes are always nested or inner class<\/li>\n
You can use access modifier for static class<\/li>\n<\/ul>\n
Example Code Snippet<\/strong><\/p>\n<\/div>\n
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public class SampleClass{<\/span><\/p>\n
\u00a0\u00a0\u00a0 \/\/static class declared here<\/span><\/p>\n
\u00a0\u00a0\u00a0 static class SampleStaticClass{<\/span><\/p>\n
\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0 int a = 10;<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
\u00a0\u00a0\u00a0<\/span><\/p>\n
\u00a0\u00a0\u00a0 public static void main(String args[]) {<\/span><\/p>\n
\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0 SampleClass.SampleStaticClass staticClass = new SampleClass.SampleStaticClass();<\/span><\/p>\n
\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(staticClass.a);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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4. What is this final keyword? how I can be used?<\/a><\/h3>\n
The final keyword is used for restricting the behavior variable, method, class, etc.<\/p>\n
The final keyword can be used with<\/p>\n
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Variable<\/li>\n
Methods<\/li>\n
Class<\/li>\n<\/ul>\n
Final Variable:<\/strong><\/p>\n
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If you prefix any variable with a final keyword then it is called the final variable.<\/li>\n
Once the value is assigned to the final variable you cannot change it.<\/li>\n
If you don\u2019t initialize the final variable during declaration it is called blank final variable, it can be initialized through constructor.<\/li>\n
A\u00a0 final variable can be declared as a static<\/li>\n
You can assign the final static variable during the declaration<\/li>\n
If you have created a blank static final variable, it can be initialized inside the static block.<\/li>\n<\/ul>\n
Example Code Snippet<\/span><\/p>\n<\/div>\n
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public class FinalTest{<\/span><\/p>\n
\u00a0\u00a0\u00a0 public static void main(String args[]) {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 final int i = 10;<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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Final Methods<\/strong><\/p>\n
If you prefix the final keyword to methods it becomes the final method<\/p>\n
Final methods cannot be overridden<\/p>\n
Static final method is completely valid in java, and it can be declared<\/p>\n
Example Code Snippet<\/strong><\/p>\n<\/div>\n
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final void print() {<\/span><\/p>\n
\u00a0\u00a0\u00a0 int a = 10;<\/span><\/p>\n
\u00a0\u00a0\u00a0 System.out.println(a);<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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Final Class<\/strong><\/p>\n
If you prefix final to class, then it becomes the final class<\/p>\n
Final classes cannot be extended or inherited<\/p>\n
You can create the inner class as a static final<\/p>\n
Example Code Snippet<\/strong><\/p>\n<\/div>\n
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public final class<\/span><\/p>\n
{<\/span><\/p>\n
\u00a0\u00a0 \/\/Some Code<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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5. What is the difference between method overloading and method overriding?<\/a><\/h3>\n
Method overloading is class has more than one method of the same name but having different parameter. Method overriding Subclass provides the implementation of the method that has been declared by the Parent class is called method overriding.<\/p>\n
Method overloading is an example of compile-time polymorphism. Method overriding is an example of run time polymorphism.<\/p>\n
You cannot achieve overloading only by changing the return type. Method overriding will have usually the same return type.<\/p>\n
Method overloading can be achieved without inheritance. Method overriding requires inheritance<\/p>\n
Example Code Snippet for method overloading<\/strong><\/p>\n<\/div>\n
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\/\/Method overloading<\/span><\/p>\n
public class SampleClass{<\/span><\/p>\n
\u00a0\u00a0\u00a0 public void add(int a, int b, int c) {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \/\/some code<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
\u00a0\u00a0\u00a0 public void add(int a, int b) {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \/\/some code<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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Example Code Snippet for Method overriding<\/strong><\/p>\n<\/div>\n
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\/\/Method overriding<\/span><\/p>\n
public class SampleClass{<\/span><\/p>\n
\u00a0\u00a0\u00a0 public void someMethod() {<\/span><\/p>\n
\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“Super Class”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n
class MyClass extends SampleClass{<\/span><\/p>\n
\u00a0\u00a0\u00a0 public void someMethod() {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“Sub Class”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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6. Could you explain IS-A and HAS-A relationship?<\/h3>\n
IS -A relationship<\/strong><\/p>\n
IS-A relationship<\/strong> is formed in inheritance, The class which inherit is known as subclass or child class. That means that child class is the type of parent class.<\/p>\n
For example, Orange is a Fruit, you need to extend fruit class to make IS-A relationship\u00a0 <\/strong><\/p>\n
Example Code Snippet\u00a0 : IS-A Relationship<\/strong><\/p>\n<\/div>\n
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class Fruit{<\/span><\/p>\n
\u00a0\u00a0\u00a0 \/\/some code<\/span><\/p>\n
}<\/span><\/p>\n
\/\/IS-A relationship<\/span><\/p>\n
class Orange extends Fruit {<\/span><\/p>\n
\/\/some code<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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HAS -A relationship<\/strong><\/p>\n
HAS-A relationship<\/strong> is composition, which means you are creating the object of a class inside another class. Let\u2019s take the example of Room. The room has a chair. The room should contain chair class reference, i.e you need to create an instance of Chair particular class inside the Room class.<\/p>\n
Example Code Snippet : HAS-A Relationship<\/strong><\/p>\n<\/div>\n
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class Room {<\/span><\/p>\n
\u00a0\u00a0\u00a0 Chair chair = new Chair();<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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7. Explain this and super keyword<\/a><\/h3>\n
this<\/strong> keyword is used to refer current class instance\/object<\/p>\n
this keyword<\/strong> can be used to<\/p>\n
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Current class instance variable<\/li>\n
Invoke current class methods<\/li>\n
Invoke current class constructor<\/li>\n
Can be used to pass the argument to a method<\/li>\n
Can be used to pass the argument to a constructor<\/li>\n
Return the current class instance<\/li>\n<\/ul>\n
Super Keyword<\/strong><\/p>\n
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The super keyword is a reference variable that is used to refer to parent class objects<\/li>\n
super can be used to refer to immediate parent class instance variable<\/li>\n
super can be used to invoke the parent class method<\/li>\n
super can be used to invoke parent class Constructor<\/li>\n<\/ul>\n
Example Code Snippet : this and super keywords<\/strong><\/p>\n<\/div>\n
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class First {<\/span><\/p>\n
\u00a0\u00a0\u00a0 void print() {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“Printing First…”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n
class Second extends First {<\/span><\/p>\n
\u00a0\u00a0\u00a0 void printOneMore() {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“Printing Second…”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
\u00a0\u00a0\u00a0 void myMethod() {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 super.print();<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 this.printOneMore();<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n
public class KeywordTest {<\/span><\/p>\n
\u00a0\u00a0\u00a0 public static void main(String args[]) {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Second d = new Second();<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 d.myMethod();<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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8. How to check instance of Specified type? Explain with example<\/a><\/h3>\n
The Java provides instanceof<\/strong> operater which can be used to check instance of Specified type.<\/p>\n
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The instanceof<\/strong> operator returns either true or false<\/li>\n
The instanceof<\/strong> operators are used for down casting<\/li>\n
The instanceof<\/strong> operator works on the principle of the is-a relationship<\/li>\n
If you instanceof<\/strong> Operator for null object it will return false.<\/li>\n<\/ul>\n
Example Code Snippet<\/strong><\/p>\n<\/div>\n
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public class Apple {<\/span><\/p>\n
\u00a0\u00a0\u00a0 public static void main(String args[]) {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Apple apl = new Apple();<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 if (apl instanceof Apple) {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0 System.out.println(“apl is instance of Apple”);<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 } else {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“apl is not an instance of Apple”);<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 }<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
\n
9. What is a package in Java? What are different types of packages? Can we create a custom package?<\/a><\/h3>\n
\n
A package is a group of similar interfaces, classes, and subclasses<\/li>\n
Custom package can be created with the package keyword<\/li>\n
Access modified can be used for packages<\/li>\n
Import keyword is used for importing already created packages.<\/li>\n
The package is a good example of java encapsulation<\/li>\n
Packages that are inside another package are the sub-packages<\/li>\n
Java provides many built-in packages and it allows you to create custom ones as well<\/li>\n<\/ul>\n<\/div>\n
\n
Some of the built-in packages are<\/strong><\/p>\n
java.lang : <\/strong>This package contains the classes and interfaces that are fundamental to the core Java<\/p>\n
java.util<\/strong> : This library provides users with generic java utilities like collections framework, formatted printing and scanning, array manipulation utilities, event model, date and time facilities, internationalization, and miscellaneous utility classes<\/p>\n
java.io<\/strong> This library is very useful and contains the classes that handle fundamental input and output operations in Java<\/p>\n
java.net<\/strong> : This package contains classes and interfaces that provide a powerful infrastructure for networking in Java.<\/p>\n
java.sql :<\/strong> This package contains all the SQL-related classes and interfaces. This package provides the API for accessing and processing data stored in a data source.<\/p>\n
We can create custom packages in Java<\/strong><\/p>\n
Example Code Snippet<\/strong><\/p>\n<\/div>\n
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<\/div>\n
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package packageName; \/\/ Use package keyword for creation<\/span><\/p>\n
public class ExampleClass{\u00a0<\/span><\/p>\n
\u00a0\/\/ Some Code Here<\/span><\/p>\n
} <\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
\n
10. What is run time polymorphism in Java?<\/a><\/h3>\n
Runtime polymorphism or Dynamic Method Dispatch is a process in which a call to an overridden method is resolved at runtime rather than compile-time.<\/p>\n
\n
The overridden method is called through the reference variable of a superclass<\/li>\n
The object is determined by the object being referred to by the reference variable<\/li>\n
The reference variable of Parent class refers to the object of Child class is called upcasting<\/li>\n<\/ul>\n<\/div>\n
\n
<\/div>\n
\n
\n
class Car {<\/span><\/p>\n
\u00a0\u00a0\u00a0 void print() {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“Inside Car Class”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n
class Honda extends Car {<\/span><\/p>\n
\u00a0\u00a0\u00a0 void print() {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“Inside Honda Class”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n
public class MainClass {<\/span><\/p>\n
\u00a0\u00a0\u00a0 public static void main(String args[]) {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Car car = new Honda();\/\/ This is Upcasting<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 car.print();<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
\n
11. What is the difference between static and dynamic binding in java?<\/a><\/h3>\n
\n
The binding which can be resolved by the compile-time is static binding. The binding which will be resolved at the run time is known as dynamic binding.<\/li>\n
Type information is used for resolving static binding. Object information is used for resolving dynamic binding<\/li>\n
Method overloading is an example of static binding. Method overriding is an example of dynamic binding<\/li>\n
Static binding is also known as early binding. Dynamic binding is also known as late binding<\/li>\n<\/ul>\n
Example Code Snippet: Static Binding <\/strong><\/p>\n<\/div>\n
\n
<\/div>\n
\n
\n
\/\/Static binding<\/span><\/p>\n
public class MainClass {<\/span><\/p>\n
\u00a0\u00a0\u00a0 void print() {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“Printing”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
\u00a0\u00a0\u00a0 public static void main(String args[]) {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 MainClass mc = new MainClass();<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 mc.print();<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
\n
Example Code Snippet: Dynamic binding <\/strong><\/p>\n<\/div>\n
\n
<\/div>\n
\n
\n
\/\/Dynamic Binding<\/span><\/p>\n
class Fruit {<\/span><\/p>\n
\u00a0\u00a0\u00a0 void print() {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“This is fruit class”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n
public class Apple extends Fruit {<\/span><\/p>\n
\u00a0\u00a0\u00a0 void print() {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println(“This is Apple”);<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
\u00a0\u00a0\u00a0 public static void main(String args[]) {<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Fruit f = new Apple();<\/span><\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 f.print();<\/span><\/p>\n
\u00a0\u00a0\u00a0 }<\/span><\/p>\n
}<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n
\n
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SDET\/QA Automation Interview Kit + Java logic Programs<\/a><\/span><\/li>\n<\/ul>\n<\/div>\n
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A Quick Note<\/strong><\/em><\/h4>\n<\/div>\n\n
Please remember all these courses comes with 100% Lifetime acces<\/strong>s<\/strong> and free updates for Lifetime!!<\/strong><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n
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Please click on the link Sr.QA and SDET Interview Questions in Java \u2013 Part 2<\/a><\/em><\/span><\/strong> to continue to part-2 series of this article.<\/p>\n<\/div>\n<\/div>\n<\/div>\n
<\/div>\n<\/section>\n
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This is Part 1 in the series of SDET Interview questions and answers in Java table of contents This is Part 1 in the series of SDET Interview questions and answers in Java 1. What is the difference between JDK, JRE, and JVM? 2. What are the different types of constructors in Java? And How […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,5],"tags":[],"class_list":["post-1214","post","type-post","status-publish","format-standard","hentry","category-interview-questions","category-java","post-wrapper","thrv_wrapper"],"_links":{"self":[{"href":"https:\/\/rahulshettyacademy.com\/blog\/index.php\/wp-json\/wp\/v2\/posts\/1214","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rahulshettyacademy.com\/blog\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rahulshettyacademy.com\/blog\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rahulshettyacademy.com\/blog\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/rahulshettyacademy.com\/blog\/index.php\/wp-json\/wp\/v2\/comments?post=1214"}],"version-history":[{"count":0,"href":"https:\/\/rahulshettyacademy.com\/blog\/index.php\/wp-json\/wp\/v2\/posts\/1214\/revisions"}],"wp:attachment":[{"href":"https:\/\/rahulshettyacademy.com\/blog\/index.php\/wp-json\/wp\/v2\/media?parent=1214"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rahulshettyacademy.com\/blog\/index.php\/wp-json\/wp\/v2\/categories?post=1214"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rahulshettyacademy.com\/blog\/index.php\/wp-json\/wp\/v2\/tags?post=1214"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}