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Java reflection get return from method with argument mod#
Java reflection get return from method with argument code#

However, the complete syntax of declaring a method is modifier static returnType nameOfMethod (parameter1, parameter2. This is the simple syntax of declaring a method. We will learn more about return types later in this tutorial. In the above example, the name of the method is adddNumbers(). The syntax to declare a method is: returnType methodName(). Let's first learn about user-defined methods. Standard Library Methods: These are built-in methods in Java that are available to use.User-defined Methods: We can create our own method based on our requirements.You can create two methods to solve this problem:ĭividing a complex problem into smaller chunks makes your program easy to understand and reusable. Suppose you need to create a program to create a circle and color it.

Java reflection get return from method with argument code#

For example, import method is a block of code that performs a specific task. However, the reflection of private field is little bit different than the public field. Similarly, we can also access and modify private fields as well. field1.getModifiers() - returns the value of the field in integer form.field1.get() - returns the value of field.We then used various methods of the Field class: Here, we are accessing the public field of the Dog class and assigning it to the object field1 of the Field class. Notice the statement, Field field1 = obj.getField("type") It will return all the public fields in both the class and all superclasses. In the above example, we have created a class named Dog. The getFields () method returns all accessible public fields of the class in question.

String modifier1 = Modifier.toString(mod) get the access modifier of the field type String typeValue = (String) field1.get(d1) Like methods, we can also inspect and modify different fields of a class using the methods of the Field class. To learn more, visit the Java Method class (official Java documentation).

The Method class also provides various other methods that can be used to inspect methods at run time.

m.getReturnType() - returns the return type of methods.

m.getModifiers() - returns the access modifier of methods in integer form.

m.getName() - returns the name of a method.

Here, the getDeclaredMethod() returns all the methods present inside the class.Īlso, we have created an object m of the Method class. Notice the expression, Method methods = obj.getDeclaredMethod() As mentioned earlier, we have first created an object obj of Class using the getClass() method. In the above example, we are trying to get information about the methods present in the Dog class. ("Modifier: " + Modifier.toString(modifier)) Method methods = obj.getDeclaredMethods() The Method class provides various methods that can be used to get information about the methods present in a class.

Constructor class - provides information about constructors in a class.

Field class - provides information about fields in a class.

Method class - provides information about methods in a class.

The package provides classes that can be used for manipulating class members. Reflecting Fields, Methods, and Constructors Note: We are using the Modifier class to convert the integer access modifier to a string. To learn more about Class, visit Java Class (official Java documentation).

obj.getSuperclass() - returns the super class of the class.

obj.getModifiers() - returns the access modifier of the class.

obj.getName() - returns the name of the class.

Using the object, we are calling different methods of Class. Here, we are creating an object obj of Class using the getClass() method. Notice the statement, Class obj = d1.getClass() Here, we are trying to inspect the class Dog. In the above example, we have created a superclass: Animal and a subclass: Dog.

Java reflection get return from method with argument mod#

String mod = Modifier.toString(modifier) put this class in different Dog.java file We can use this object to get information about the corresponding class at runtime.Įxample: Java Class Reflection import Now that we know how we can create objects of the Class. class extension // create an object of Class Here, we are using the object of the Dog class to create an object of Class.ģ. Using getClass() method // create an object of Dog class Here, the forName() method takes the name of the class to be reflected as its argument.Ģ. There exists three ways to create objects of Class:ġ. In order to reflect a Java class, we first need to create an object of Class.Īnd, using the object we can call various methods to get information about methods, fields, and constructors present in a class.

The object of Class can be used to perform reflection. There is a class in Java named Class that keeps all the information about objects and classes at runtime. In Java, reflection allows us to inspect and manipulate classes, interfaces, constructors, methods, and fields at run time.