The java.lang.reflect.Method.getDeclaringClass() method of Method class returns the Class object for the class or interface which defines the method on which we are applying this getDeclaringClass() method.
Syntax:
public Class<?> getDeclaringClass()
Return Value: This method returns the Class object in which method is declared.
Below program illustrates getDeclaringClass() method of Method class:
Program 1: To find the details of class Object which defined the method, by applying getDeclaringClass() method.
In below program a Demo class with some methods is created. After creating the class object, the list of method objects is created by calling getMethods() function of class object. Then they are looped through the list and the details of declaring class of each method are printed.
Output of this program also shows results for method objects other than methods defined in class object like wait, equals, toString, hashCode, getClass, notify, and notifyAll. These methods are inherited from superclass Object of java.lang package by class object.
// Program Demonstrate getDeclaringClass() method// of Method Class. import java.lang.reflect.Method; // sample class containing some methodclass GFGDemoClass { // create attributes private String field1; private String field2; // create methods public String getField1() { return field1; } public void setField1(String field1) { this.field1 = field1; } public String getField2() { return field2; } public void setField2(String field2) { this.field2 = field2; }} // class containing the Main methodpublic class GFG { public static void main(String[] args) { // get array Method objects of GFGDemoClass Method[] methods = GFGDemoClass.class.getMethods(); // print getDeclaringclass for every Method object // looping through a list of method objects for (Method m : methods) { // get a class object which declares the current method // by declaringClass() method Class declaringClass = m.getDeclaringClass(); // print Method name and class name System.out.println("Method Name: " + m.getName()); System.out.println("Declaring class Name: " + declaringClass.getName()); } }} |
Method Name: getField1 Declaring class Name: GFGDemoClass Method Name: setField1 Declaring class Name: GFGDemoClass Method Name: getField2 Declaring class Name: GFGDemoClass Method Name: setField2 Declaring class Name: GFGDemoClass Method Name: wait Declaring class Name: java.lang.Object Method Name: wait Declaring class Name: java.lang.Object Method Name: wait Declaring class Name: java.lang.Object Method Name: equals Declaring class Name: java.lang.Object Method Name: toString Declaring class Name: java.lang.Object Method Name: hashCode Declaring class Name: java.lang.Object Method Name: getClass Declaring class Name: java.lang.Object Method Name: notify Declaring class Name: java.lang.Object Method Name: notifyAll Declaring class Name: java.lang.Object
Program 2: To find the details of Object class methods, by applying getDeclaringClass() method.
// Program Demonstrate getDeclaringClass() method// of Method Class. import java.lang.reflect.Method; // sample class containing some methodclass BasicOperations { // create attributes int a; int b; // create methods public int add() { return a + b; } public int multiply() { return a * b; } public int subtract() { return a - b; } public int division() { return a / b; }} public class GFG { public static void main(String[] args) { // get array Method objects Method[] methods = BasicOperations.class.getMethods(); // print getDeclaringclass for every Method object for (Method m : methods) { // get class object by declaringClass() method Class declaringClass = m.getDeclaringClass(); // checks whether the method belong to // BasicOperations class or not // and if yes then print method name // along with declaring class name. if (declaringClass.getName().equals("BasicOperations")) { // print Method name and class name System.out.println("Method Name: " + m.getName()); System.out.println("Declaring class Name: " + declaringClass.getName()); } } }} |
Method Name: multiply Declaring class Name: BasicOperations Method Name: subtract Declaring class Name: BasicOperations Method Name: division Declaring class Name: BasicOperations Method Name: add Declaring class Name: BasicOperations
Reference: https://docs.oracle.com/javase/8/docs/api/java/lang/reflect/Method.html#getDeclaringClass–
