com.hazelcast.config.cp.SemaphoreConfig Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2024, Hazelcast, Inc. All Rights Reserved.
*
* 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 com.hazelcast.config.cp;
import com.hazelcast.core.HazelcastInstance;
import com.hazelcast.cp.ISemaphore;
import java.util.concurrent.Semaphore;
import static com.hazelcast.internal.util.Preconditions.checkNotNegative;
/**
* Contains configuration options for CP {@link ISemaphore}
*/
public class SemaphoreConfig {
/**
* The default value for the JDK compatibility mode
* of CP {@link ISemaphore}
*/
public static final boolean DEFAULT_SEMAPHORE_JDK_COMPATIBILITY = false;
/**
* Default value for the initial permit count of Semaphores.
*/
public static final int DEFAULT_INITIAL_PERMITS = 0;
/**
* Name of CP ISemaphore
*/
private String name;
/**
* Enables / disables JDK compatibility of CP {@link ISemaphore}.
* When it is JDK compatible, just as in the {@link Semaphore#release()}
* method, a permit can be released without acquiring it first, because
* acquired permits are not bound to threads. However, there is no
* auto-cleanup mechanism for acquired permits upon Hazelcast
* server / client failures. If a permit holder fails, its permits must be
* released manually. When JDK compatibility is disabled,
* a {@link HazelcastInstance} must acquire permits before releasing them,
* and it cannot release a permit that it has not acquired. It means, you
* can acquire a permit from one thread and release it from another thread
* using the same {@link HazelcastInstance}, but not different
* {@link HazelcastInstance}s. In this mode, acquired permits are
* automatically released upon failure of the holder
* {@link HazelcastInstance}. So there is a minor behavioral difference
* to the {@link Semaphore#release()} method.
*
* JDK compatibility is disabled by default.
*/
private boolean jdkCompatible = DEFAULT_SEMAPHORE_JDK_COMPATIBILITY;
/**
* Number of permits to initialize the Semaphore. If a positive value is
* set, the Semaphore is initialized with the given number of permits.
*/
private int initialPermits = DEFAULT_INITIAL_PERMITS;
public SemaphoreConfig() {
super();
}
public SemaphoreConfig(String name) {
this.name = name;
}
public SemaphoreConfig(String name, boolean jdkCompatible, int initialPermits) {
this.name = name;
this.jdkCompatible = jdkCompatible;
this.initialPermits = initialPermits;
}
SemaphoreConfig(SemaphoreConfig config) {
this.name = config.name;
this.jdkCompatible = config.jdkCompatible;
this.initialPermits = config.initialPermits;
}
/**
* Returns the name of CP ISemaphore
*/
public String getName() {
return name;
}
/**
* Sets the name of CP ISemaphore
*/
public SemaphoreConfig setName(String name) {
this.name = name;
return this;
}
/**
* Returns true if CP ISemaphore is compatible with
* its JDK counterpart
*/
public boolean isJDKCompatible() {
return jdkCompatible;
}
/**
* Sets JDK compatibility mode of CP ISemaphore
*/
public SemaphoreConfig setJDKCompatible(boolean jdkCompatible) {
this.jdkCompatible = jdkCompatible;
return this;
}
/**
* Returns initial permit count of the Semaphore
*/
public int getInitialPermits() {
return initialPermits;
}
/**
* Sets initial permit count of the Semaphore
*/
public SemaphoreConfig setInitialPermits(int initialPermits) {
checkNotNegative(initialPermits, "initial permits cannot be negative");
this.initialPermits = initialPermits;
return this;
}
@Override
public String toString() {
return "SemaphoreConfig{" + "name='" + name + '\'' + ", jdkCompatible=" + jdkCompatible + ", initialPermits="
+ initialPermits + '}';
}
}