jnr.ffi.annotations.Direct Maven / Gradle / Ivy
/*
* Copyright (C) 2008-2010 Wayne Meissner
*
* This file is part of the JNR project.
*
* Licensed 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 jnr.ffi.annotations;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Indicates that a {@link jnr.ffi.Struct}} parameter should be
* backed by a persistent native memory block.
*
* Without the {@code @Direct} annotation, the native code will allocate a
* temporary native memory block for the parameter, and free it immediately after
* the call.
*
*
By using {@code @Direct}, the native memory block is permanently associated
* with the {@link jnr.ffi.Struct} instance, and will remain allocated
* for as long as the {@code Struct} instance remains strongly referenced by java code.
*
*/
@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.PARAMETER, ElementType.ANNOTATION_TYPE })
public @interface Direct {
}