toString Method in Java – How to Use It (with Examples)

The ‘toString’ method in Java is essential to the Java programming language. It is widely used for converting objects into a string representation. The ‘toString’ method is defined in the Object class. The Object class is the superclass of all the sub-classes, meaning every object in Java has access to the ‘toString’ method. This article explained the toString method.

What is toString() Method in Java

The toString() method is the built-in method in Java. That provides a string representation of an object. The toString() method is quite useful in that it allows string representations of objects. It can be useful during debugging, logging, and displaying information about the objects as human-readable text.

The following program demonstrates the toString() method:

Program

Output

Overriding the ‘toString()’ method in Java allows you to define a custom string representation for an object. The detailed explanation and example of “how to override the ‘toString()’ method in Java.

The following program demonstrates the toString() method:

Program:

Output  

Java Classes with toString() Overridden by Default

In Java, All the wrapper classes like Byte, Integer, Long, Float, Double, Boolean, and Character have overridden the toString() method. The collection classes, such as String and StringBulder, have also overridden the toString() method.

Source Code:

Output

Using static toString() method in Wrapper Classes

The Wrapper classes in Java implement the ‘toString()’ method statically. We can directly get the String value without defining an object of the class.

The following program demonstrates the toString() method:

Program

Output

Using valueOf() Method in String Class

The valueOf() method in the ‘String’ class is a versatile utility in Java that converts different data types into their corresponding ‘String’ representation. This method is particularly useful when converting primitive data types, objects, or arrays into a ‘String’.

The following program demonstrates the valueOf() method in Java:

Output

Best Practices for Overriding ‘toString()’

Let’s see some best practices for overriding the method.

• Keep it Simple: The string method should be simple and informative. That must include only the essential information that defines the object.
• Avoid Sensitive Information: Developers must not include sensitive data like passwords or personal information.
• Use StringBuilder: It performs better, especially when concatenating multiple strings. Use ‘StringBuilder’ instead of ‘+’ for string concatenation.
• Ensure Readability: The output of the ‘toString()’ method should be easily readable and understandable to the person who will see it.
• Improved Readability: For complex objects, especially in large applications, a well-defined ‘toString()’ method helps make the output more human readable. This is particularly useful for developers who are working with or maintaining the source code.

Conclusion

Java’s ‘toString()’ method is fundamental for converting objects into a human-readable string format. By overriding this method, you can customize how objects are represented as strings, enhancing the clarity and usefulness of the output whether working with custom classes, wrapper classes, or using the ‘valueOf()’ method in the ‘String’ class, understanding and effectively implementing ‘toString()’ will improve your code’s readability and debugging process.