Project Lombok allows developers to add annotations to reduce boilerplate code. It works by using annotation processing at compile time to modify bytecode. Lombok provides annotations like @Getter and @Setter to automatically generate getter and setter methods. Lombok-pg extends Lombok with additional annotations. Groovy also supports compile time metaprogramming through AST transformations, allowing changes to bytecode and visibility to other JVM languages.

2. Rocket Propelled Java
Andres Almiray
Canoo Fellow
Canoo Engineering AG
@aalmiray

3. Andres Almiray
Speaker Bio
■ Java developer since the beginning
■ True believer in open source
■ Groovy committer since 2007
■ Project lead of the Griffon framework
■ Currently working for
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4. Project Lombok
Where, Who, How?
Why?
■ http://projectlombok.org/ ■ Get rid of boiler plate code
index.html
■ Compiler does the heavy lifting
■ Reinier Zwitserloot @surial
■ Developers just have to write the
■ Roel Spilker @rspilker
essentials
■ Relies on JDK6’s Annotation
Processor
■ Modifies Bytecode at compile
time
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5. How does it look?
import lombok.Data;
import lombok.ToString;
@ToString(includeFieldNames=true)
@Data public class DataExample {
private final String name;
private final String lastName;
private int age;
}
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6. Annotations
■ @Getter / @Setter
■ @Cleanup
■ @ToString
■ @Synchronized
■ @EqualsAndHashCode
■ @SneakyThrows
■ @NoArgsConstructor
■ @Log
■ @RequiredArgsConstructor
■ @Delegate
■ @AllArgsConstructor
■ @Data
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7. Lombok-pg
Where, Who, How
Why?
■ https://github.com/peichhorn/ ■ Extends Lombok with additional
lombok-pg/
annotations such as:
■ Philipp Eichhorn
■ @Singleton
■ peichhorn @ github
■ @FluentSetter
■ @Builder
■ Delivers its own common AST ■ and more!
API
■ Easier to write cross compiler
AST
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8. Groovy AST Transformations
Where, Who, How
Why?
■ https://groovy.codehaus.org
■ Groovy plays nicely with Java
■ The Groovy Team
■ Compile time metaprogramming
executes faster than runtime
■ Compile time metaprogramming
■ Changes visible to other JVM
■ Changes registered in the languages
bytecode
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9. Some Annotations
■ @Bindable / @Vetoable
■ @Delegate
■ @Grab
■ @Log
■ @Immutable
■ @Synchronized
■ @Singleton
■ @AutoClone
■ @ToString
■ @AutoExternalize
■ @EqualsAndHashCode
■ @TupleConstructor
■ @TypeChecked
■ @Canonical
■ @CompileStatic
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10. Q&A
Andres Almiray
@aalmiray