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/*
* Copyright (C) 2010-2017 The Project Lombok Authors.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package lombok.experimental;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Put on any field to make lombok generate delegate methods that forward the call to this field.
*
* Example:
*
* private @Delegate List<String> foo;
*
*
* will generate for example an {@code boolean add(String)} method, which contains: {@code return foo.add(arg);}, as well as all other methods in {@code List}.
*
* All public instance methods of the field's type, as well as all public instance methods of all the field's type's superfields are delegated, except for all methods
* that exist in {@link Object}, the {@code canEqual(Object)} method, and any methods that appear in types
* that are listed in the {@code excludes} property.
*
* Complete documentation is found at the project lombok features page for @Delegate.
*/
@Target({ElementType.FIELD, ElementType.METHOD})
@Retention(RetentionPolicy.SOURCE)
public @interface Delegate {
/**
* Normally the type of the field is used as delegate type. However, to choose a different type to delegate, you can list one (or more) types here. Note that types with
* type arguments can only be done as a field type. A solution for this is to create a private inner interface/class with the appropriate types extended, and possibly
* with all methods you'd like to delegate listed, and then supply that class here. The field does not actually have to implement the type you're delegating; the
* type listed here is used only to determine which delegate methods to generate.
*
* NB: All methods in {@code Object}, as well as {@code canEqual(Object other)} will never be delegated.
*
* @return For each method (not already in {@code java.lang.Object}) in these types, generate a delegate method.
*/
Class[] types() default {};
/**
* Each method in any of the types listed here (include supertypes) will not be delegated.
*
* NB: All methods in {@code Object}, as well as {@code canEqual(Object other)} will never be delegated.
*
* @return For each method (not already in {@code java.lang.Object}) in these types, skip generating a delegate method (overrides {@code types()}).
*/
Class[] excludes() default {};
}