Java: Get Class Name

In Java, obtaining the class name of an object or a class is a common task, often used for debugging, logging, or reflection. This guide will cover different ways to get the class name, including using the getClass method and the Class class.

Table of Contents

1. Introduction
2. Using getClass().getName()
3. Using Class.getName()
4. Getting the Simple Class Name
5. Conclusion

Introduction

Java provides several methods to get the name of a class. These methods are useful in various scenarios, such as logging the class name for debugging purposes or performing operations using reflection.

Using getClass().getName()

The getClass().getName() method is used to get the class name of an object. This method is called on an instance of the class.

Example

public class ClassNameExample {
    public static void main(String[] args) {
        MyClass myObject = new MyClass();
        String className = myObject.getClass().getName();
        System.out.println("Class name: " + className);
    }
}

class MyClass {
    // Class implementation
}

Explanation

• myObject.getClass(): Returns the runtime class of the object myObject.
• getClass().getName(): Returns the fully qualified name of the class.

Output:

Class name: MyClass

Using Class.getName()

You can also get the class name directly from the class itself using Class.getName().

Example

public class ClassNameExample {
    public static void main(String[] args) {
        String className = MyClass.class.getName();
        System.out.println("Class name: " + className);
    }
}

class MyClass {
    // Class implementation
}

Explanation

• MyClass.class: Obtains the Class object associated with the MyClass.
• class.getName(): Returns the fully qualified name of the class.

Output:

Class name: MyClass

Getting the Simple Class Name

If you are only interested in the simple name of the class (i.e., without the package name), you can use the getSimpleName() method.

Example

public class ClassNameExample {
    public static void main(String[] args) {
        MyClass myObject = new MyClass();
        String simpleClassName = myObject.getClass().getSimpleName();
        System.out.println("Simple class name: " + simpleClassName);
    }
}

class MyClass {
    // Class implementation
}

Explanation

• getClass().getSimpleName(): Returns the simple name of the class (without the package name).

Output:

Simple class name: MyClass

Conclusion

Obtaining the class name in Java can be accomplished using various methods, including getClass().getName(), Class.getName(), and getClass().getSimpleName(). Each method has its own advantages and specific use cases:

• The getClass().getName() method is useful when you have an instance of the class.
• The Class.getName() method is useful when you are working directly with the class.
• The getClass().getSimpleName() method is useful when you need only the simple name of the class without the package name.

By understanding these methods, you can choose the most appropriate one for your specific use case when working with class names in Java.