Check out example codes for "java method overriding". It will help you in understanding the concepts better.

Code Example 1

using method-override in your index.js
1. npm install method-override --save
2. var methodOverride = require("method-override");
3. app.use(methodOverride("_method"));
//'_method' is what methodOverride will look for
method override in your UPDATE route: 
* <form action = "/campgrounds/<%=campground._id%>/edit?_method=PUT" 
	method = "POST">
and EDIT routes:

Code Example 2

// Base Class 
class Parent { 
    void show(){ 
        System.out.println("Parent's show()"); 
    } 
} 
// Inherited Class 
class Child extends Parent { 
    // This method overrides show() of Parent Class
    @Override
    void show(){ 
        System.out.println("Child's show()"); 
    } 
}
// Main class 
class Main { 
    public static void main(String[] args){ 
        Parent obj = new Child(); 
		// Calling Child Class Method
        obj.show(); 
    } 
}

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