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Java Class class getField() method with example

Class class getField() method: Here, we are going to learn about the getField() method of Class class with its syntax and example.
Submitted by Preeti Jain, on November 14, 2019

Class class getField() method

• getField() method is available in java.lang package.
• getField() method is used to return a Field objects that indicate the given public member field of the class or an interface denoted by this Class object.
• getField() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.
• getField() method may throw an exception at the time of returning a Field object.
  • NoSuchFieldException: In this exception when a specifying field does not exist.
  • SecurityException: In this exception, it may raise when the security manager exists.
  • NullPointerException: In this exception when the given field is null.

Syntax:

    public Field getField (String field_name);

Parameter(s):

• String field_name – represents the name of the field.

Return value:

The return type of this method is Field, it returns Field object of the given Field in this Class.

Example:

// Java program to demonstrate the example 
// of Field getField (String field_name) method of Class 

import java.lang.reflect.*;

public class GetFieldOfClass {
    public static void main(String[] args) throws Exception {
        GetFieldOfClass field = new GetFieldOfClass();

        // Get Class
        Class cl = field.getClass();

        // By using getField() method is to get the public field of
        // the class 
        Field f = cl.getField("i");
        System.out.println("Field: " + f.toString());
    }

    // Private Constructors
    private GetFieldOfClass() {
        System.out.println("We are in private constructor");
    }

    // Public Constructors
    public GetFieldOfClass(int i) {
        this.i = i;
    }

    public int i = 100;
}

Output

We are in private constructor
Field: public int GetFieldOfClass.i