groovy.transform.TupleConstructor Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
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* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package groovy.transform;
import org.codehaus.groovy.transform.GroovyASTTransformationClass;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Class annotation used to assist in the creation of tuple constructors in classes.
* Do not use with {@link InheritConstructors}.
*
* It allows you to write classes in this shortened form:
*
* {@code @groovy.transform.TupleConstructor} class Customer {
* String first, last
* int age
* Date since
* Collection favItems
* }
* def c1 = new Customer(first:'Tom', last:'Jones', age:21, since:new Date(), favItems:['Books', 'Games'])
* def c2 = new Customer('Tom', 'Jones', 21, new Date(), ['Books', 'Games'])
* def c3 = new Customer('Tom', 'Jones')
*
* The {@code @TupleConstructor} annotation instructs the compiler to execute an
* AST transformation which adds the necessary constructor method to your class.
*
* A tuple constructor is created with a parameter for each property (and optionally field and
* super properties).
* A default value is provided (using Java's default values) for all parameters in the constructor.
* Groovy's normal conventions then allows any number of parameters to be left off the end of the parameter list
* including all of the parameters - giving a no-arg constructor which can be used with the map-style naming conventions.
*
* The order of parameters is given by the properties of any super classes with most super first
* (if {@code includeSuperProperties} is set) followed by the properties of the class followed
* by the fields of the class (if {@code includeFields} is set). Within each grouping the order
* is as attributes appear within the respective class.
*
More examples:
*
* //--------------------------------------------------------------------------
* import groovy.transform.TupleConstructor
*
* @TupleConstructor()
* class Person {
* String name
* List likes
* private boolean active = false
* }
*
* def person = new Person('mrhaki', ['Groovy', 'Java'])
*
* assert person.name == 'mrhaki'
* assert person.likes == ['Groovy', 'Java']
*
* person = new Person('mrhaki')
*
* assert person.name == 'mrhaki'
* assert !person.likes
*
*
* //--------------------------------------------------------------------------
* // includeFields in the constructor creation.
* import groovy.transform.TupleConstructor
*
* @TupleConstructor(includeFields=true)
* class Person {
* String name
* List likes
* private boolean active = false
*
* boolean isActivated() { active }
* }
*
* def person = new Person('mrhaki', ['Groovy', 'Java'], true)
*
* assert person.name == 'mrhaki'
* assert person.likes == ['Groovy', 'Java']
* assert person.activated
*
*
* //--------------------------------------------------------------------------
* // use force attribute to force creation of constructor
* // even if we define our own constructors.
* import groovy.transform.TupleConstructor
*
* @TupleConstructor(force=true)
* class Person {
* String name
* List likes
* private boolean active = false
*
* Person(boolean active) {
* this.active = active
* }
*
* boolean isActivated() { active }
* }
*
* def person = new Person('mrhaki', ['Groovy', 'Java'])
*
* assert person.name == 'mrhaki'
* assert person.likes == ['Groovy', 'Java']
* assert !person.activated
*
* person = new Person(true)
*
* assert person.activated
*
*
* //--------------------------------------------------------------------------
* // include properties and fields from super class.
* import groovy.transform.TupleConstructor
*
* @TupleConstructor(includeFields=true)
* class Person {
* String name
* List likes
* private boolean active = false
*
* boolean isActivated() { active }
* }
*
* @TupleConstructor(callSuper=true, includeSuperProperties=true, includeSuperFields=true)
* class Student extends Person {
* List courses
* }
*
* def student = new Student('mrhaki', ['Groovy', 'Java'], true, ['IT'])
*
* assert student.name == 'mrhaki'
* assert student.likes == ['Groovy', 'Java']
* assert student.activated
* assert student.courses == ['IT']
*
*
* Limitations:
*
* - Groovy's normal map-style naming conventions will not be available if the first property (or field)
* has type {@code LinkedHashMap} or if there is a single Map, AbstractMap or HashMap property (or field)
*
*
* @author Paul King
* @since 1.8.0
*/
@java.lang.annotation.Documented
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.TYPE})
@GroovyASTTransformationClass("org.codehaus.groovy.transform.TupleConstructorASTTransformation")
public @interface TupleConstructor {
/**
* List of field and/or property names to exclude from the constructor.
* Must not be used if 'includes' is used. For convenience, a String with comma separated names
* can be used in addition to an array (using Groovy's literal list notation) of String values.
*/
String[] excludes() default {};
/**
* List of field and/or property names to include within the constructor.
* Must not be used if 'excludes' is used. For convenience, a String with comma separated names
* can be used in addition to an array (using Groovy's literal list notation) of String values.
*/
String[] includes() default {};
/**
* Include fields in the constructor.
*/
boolean includeFields() default false;
/**
* Include properties in the constructor.
*/
boolean includeProperties() default true;
/**
* Include fields from super classes in the constructor.
*/
boolean includeSuperFields() default false;
/**
* Include properties from super classes in the constructor.
*/
boolean includeSuperProperties() default false;
/**
* Should super properties be called within a call to the parent constructor.
* rather than set as properties
*/
boolean callSuper() default false;
/**
* By default, this annotation becomes a no-op if you provide your own constructor.
* By setting {@code force=true} then the tuple constructor(s) will be added regardless of
* whether existing constructors exist. It is up to you to avoid creating duplicate constructors.
*/
boolean force() default false;
}
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