groovy.transform.IndexedProperty Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* 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
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* 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;
/**
* Field annotation used with properties to provide an indexed getter and setter for the property.
* Groovy provides nice GPath syntax support for accessing indexed properties but Java tools
* or frameworks may expect the JavaBean style setters and getters.
*
* Example usage: suppose you have a class with the following properties:
*
* {@code @IndexedProperty} FieldType[] someField
* {@code @IndexedProperty} List otherField
* {@code @IndexedProperty} List furtherField
*
* will add the following methods to the class containing the properties:
*
* FieldType getSomeField(int index) {
* someField[index]
* }
* FieldType getOtherField(int index) {
* otherField[index]
* }
* Object getFurtherField(int index) {
* furtherField[index]
* }
* void setSomeField(int index, FieldType val) {
* someField[index] = val
* }
* void setOtherField(int index, FieldType val) {
* otherField[index] = val
* }
* void setFurtherField(int index, Object val) {
* furtherField[index] = val
* }
*
* Normal Groovy visibility rules for properties apply
* (i.e. no public, private or package
* visibility can be specified) or you will receive a compile-time error message.
* The normal Groovy property getters and setters will also be created.
*
*
More examples:
*
* import groovy.transform.IndexedProperty
*
* class Group {
* String name
* List members = []
* }
*
* class IndexedGroup {
* String name
* @IndexedProperty List members = []
* }
*
* def group = new Group(name: 'Groovy')
* group.members[0] = 'mrhaki'
* group.members[1] = 'Hubert'
* assert 2 == group.members.size()
* assert ['mrhaki', 'Hubert'] == group.members
*
* try {
* group.setMembers(0, 'hubert') // Not index property
* } catch (MissingMethodException e) {
* assert e
* }
*
* def indexedGroup = new IndexedGroup(name: 'Grails')
* indexedGroup.members[0] = 'mrhaki'
* indexedGroup.setMembers 1, 'Hubert'
* assert 2 == indexedGroup.members.size()
* assert 'mrhaki' == indexedGroup.getMembers(0)
* assert 'Hubert' == indexedGroup.members[1]
*
*
* @author Paul King
* @since 1.7.3
*/
@java.lang.annotation.Documented
@Retention(RetentionPolicy.SOURCE)
@Target({ElementType.FIELD})
@GroovyASTTransformationClass("org.codehaus.groovy.transform.IndexedPropertyASTTransformation")
public @interface IndexedProperty {
}