Introducing Lombok

What is Lombok

Lombok is a tool that can help us simplify and eliminate some necessary but bloated Java code through a simple form of annotation. By using the corresponding annotation, the corresponding method can be generated when compiling the source code.

Official address: https://projectlombok.org/ github address: https://github.com/rzwitserloot/lombok

Lombok installation

Download Lombok (1.16.20)
Add -javaagent:lombok-1.16.20.jar at the end of the eclipse.ini file

Add maven project dependencies

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <version>1.16.6</version>
</dependency>

Lombok Common Annotations

@val @var

Weakly typed variables are defined; val-annotated variables declare final types, and var-annotated variables are non-final types

@NonNull

Using @NonNull on a parameter of a method or constructor, lombok will generate a null check statement

@Getter @Setter @Accessors

Add Get and Set methods to the class, and use the @Accessors annotation to allow the set method to return to the class itself, thus realizing chain-style programming

@ToString

Add toString method to class

@EqualsAndHashCode

Add equals and hashCode methods to the class

@NoArgsConstructor

Add a no-argument constructor to a class

@RequiredArgsConstructor

A constructor that adds specified parameters to a class

@AllArgsConstructor

Add a constructor with all parameters to the class

@Data

Equivalent to @ToString + @EqualsAndHashCode + @Getter + @Setter + @RequiredArgsConstructor

@Value

Provide @Getter for final variable

@Builder

Provides builder mode

@SneakyThrows

Convert checked exceptions to unchecked exceptions

@Synchronized

类似 Synchronized 关键字，但是可以隐藏同步锁 (会生成一个内部final对象，锁会加这个内部变量，而不是类本身)

@Log @Slf4j @CommonsLog

生成各种log对象