/*
* 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 org.apache.cassandra.utils.concurrent;
/**
* An object that needs ref counting does the two following:
* - defines a Tidy object that will cleanup once it's gone,
* (this must retain no references to the object we're tracking (only its resources and how to clean up))
* Then, one of two options:
* 1) Construct a Ref directly pointing to it, and always use this Ref; or
* 2)
* - implements RefCounted
* - encapsulates a Ref, we'll call selfRef, to which it proxies all calls to RefCounted behaviours
* - users must ensure no references to the selfRef leak, or are retained outside of a method scope.
* (to ensure the selfRef is collected with the object, so that leaks may be detected and corrected)
*/
public interface RefCounted<T>
{
/**
* @return the a new Ref() to the managed object, incrementing its refcount, or null if it is already released
*/
public Ref<T> tryRef();
public Ref<T> ref();
public static interface Tidy
{
void tidy() throws Exception;
String name();
}
}