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Getting all the method and variable name from class object using reflection in java

  The java.lang.Class have some useful methods for getting information about class at run time. In this example I am going to get the all field name and variable name present in particular class using reflection.


import java.lang.reflect.Field;
import java.lang.reflect.Method;

class TestReflection {
      public int field1;
      public int field2;
     
      public void addField() {
            System.out.println("Addition of two fields: " + (field1 + field2));
      }
}

public class ReflectionDemo {

      public static void main(String[] args) {
            try{
                  TestReflection testReflection = new TestReflection();
                  Method methodNames[] = testReflection.getClass().getMethods();
                  Field fieldName[] = testReflection.getClass().getFields();
                  for(int i=0;i<methodNames.length;i++) {
                        System.out.println("Method Name: " + methodNames[i].toString());
                  }
                  System.out.println("*************************");
                  for(int i=0;i<fieldName.length;i++) {
                        System.out.println("Field Name: " + fieldName[i].toString());
                  }
            }
            catch(Exception e) {
                  e.printStackTrace();
            }
      }
}

 In this example I have created the two class for implementing reflection. The class TestReflection have two integer field field1,field2 and one method addField() for adding these two integer. In main class, I have created the one object for TestReflection class. After that I get the Class object of testReflection using getClass() method. Finally I get the all method names and field names using Class.getMethods() and Class.getFields().

Result:


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