What is ClassLoading in java? || Java Classloader || Basics of Java class loaders.

What is ClassLoading in java:-

• ClassLoading in Java is the process of loading the .class file (Byte Code) from Hard disk memory to JVM Memory. A class gets loaded only once. JVM uses ClassLoader to load the .class file.

Example 1:-

1:  class Project{  
2:       void display() {  
3:            System.out.println("Project display");  
4:       }  
5:       public static void main(String[] args) {  
6:            System.out.println("Main Start");  
7:            Project p1=new Project();  
8:            p1.display();  
9:            System.out.println("Main end");  
10:       }  
11:  }  

Here 3 Steps takes place:-

• Compilation
• ClassLoading
• Execution 

Program Flow Line by Line:-

5. (main method )

9. Print Message
10. Terminate.

Example 2:-

1:  class Project{  
2:       void display() {  
3:            System.out.println("Project display");  
4:       }  

and

1:  public class Demo{  
2:       public static void main(String[] args) {  
3:            System.out.println("Main Start");  
4:            Project p1=new Project();  
5:            p1.display();  
6:            p1.display();  
7:            System.out.println("Main end");  
8:       }  
9:  }  

Program Flow Line by Line:-

1:  public class Test {  
2:       public static void main(String[] args) {  
3:            System.out.println(10+10);  
4:            System.out.println("D"+"Demo");  
5:            System.out.println(10+3+"Demo");  
6:            System.out.println(10+10+"Demo"+10+20);  
7:       }  
8:  }