Java 8 vs MapStruct: What are the differences?

Introduction

In this article, we will discuss the key differences between Java 8 and MapStruct. Java 8 is a major release of the Java programming language that introduced several new features and enhancements, while MapStruct is a code generation tool that simplifies the implementation of mapping between Java beans.

1. Null Safety: One of the key differences between Java 8 and MapStruct is the handling of null values. In Java 8, null values can cause NullPointerExceptions when performing operations on objects, while MapStruct provides built-in null safety checks during the mapping process, preventing such runtime exceptions.

2. Code Generation: MapStruct is a code generation tool, whereas Java 8 is a programming language. MapStruct generates the mapping code at compile-time based on annotations and mappings defined in the source code. On the other hand, Java 8 requires manual implementation of mapping logic using code.

3. Mapping Flexibility: In Java 8, mapping between beans requires explicit coding of the mapping logic, which can be time-consuming and error-prone for complex mappings. MapStruct, on the other hand, provides a declarative approach to mapping configuration. It offers automatic mapping of fields with the same name and allows customization of the mapping process through annotations and custom mappers.

4. Support for Complex Mappings: Java 8 lacks built-in support for complex mappings, where multiple source fields are mapped to a single target field or vice versa. MapStruct, on the other hand, provides advanced mapping capabilities, such as parameterized mappings, mapping of nested fields, and support for custom conversions, making it more suitable for complex mapping scenarios.

5. Support for Mapping Collections: When it comes to mapping collections of objects, Java 8 requires manual iteration and mapping of each element, which can be cumbersome and time-consuming. MapStruct simplifies this process by automatically mapping collections of objects, reducing the code complexity and improving developer productivity.

6. Integration with IDEs: MapStruct offers seamless integration with popular IDEs, such as IntelliJ and Eclipse, providing features like code completion, refactoring, and error detection during the development process. Java 8, being a language itself, also provides IDE support, but it lacks the specific tooling features provided by MapStruct.

In summary, the key differences between Java 8 and MapStruct lie in null safety, code generation, mapping flexibility, support for complex mappings, handling of collections, and integration with IDEs. While Java 8 requires manual implementation of mapping logic, MapStruct automates the mapping process through code generation and provides additional features and flexibility for complex mappings and collections.