org.springframework.amqp.core.Queue.java Source code

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Here is the source code for org.springframework.amqp.core.Queue.java

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/*
 * Copyright 2002-2019 the original author or authors.
 *
 * 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
 *
 *      https://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.springframework.amqp.core;

import java.util.HashMap;
import java.util.Map;

import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;

/**
 * Simple container collecting information to describe a queue. Used in conjunction with AmqpAdmin.
 *
 * @author Mark Pollack
 * @author Gary Russell
 * @see AmqpAdmin
 */
public class Queue extends AbstractDeclarable {

    /**
     * Argument key for the master locator.
     * @since 2.1
     */
    public static final String X_QUEUE_MASTER_LOCATOR = "x-queue-master-locator";

    private final String name;

    private final boolean durable;

    private final boolean exclusive;

    private final boolean autoDelete;

    private final Map<String, Object> arguments;

    private volatile String actualName;

    /**
     * The queue is durable, non-exclusive and non auto-delete.
     *
     * @param name the name of the queue.
     */
    public Queue(String name) {
        this(name, true, false, false);
    }

    /**
     * Construct a new queue, given a name and durability flag. The queue is non-exclusive and non auto-delete.
     *
     * @param name the name of the queue.
     * @param durable true if we are declaring a durable queue (the queue will survive a server restart)
     */
    public Queue(String name, boolean durable) {
        this(name, durable, false, false, null);
    }

    /**
     * Construct a new queue, given a name, durability, exclusive and auto-delete flags.
     * @param name the name of the queue.
     * @param durable true if we are declaring a durable queue (the queue will survive a server restart)
     * @param exclusive true if we are declaring an exclusive queue (the queue will only be used by the declarer's
     * connection)
     * @param autoDelete true if the server should delete the queue when it is no longer in use
     */
    public Queue(String name, boolean durable, boolean exclusive, boolean autoDelete) {
        this(name, durable, exclusive, autoDelete, null);
    }

    /**
     * Construct a new queue, given a name, durability flag, and auto-delete flag, and arguments.
     * @param name the name of the queue - must not be null; set to "" to have the broker generate the name.
     * @param durable true if we are declaring a durable queue (the queue will survive a server restart)
     * @param exclusive true if we are declaring an exclusive queue (the queue will only be used by the declarer's
     * connection)
     * @param autoDelete true if the server should delete the queue when it is no longer in use
     * @param arguments the arguments used to declare the queue
     */
    public Queue(String name, boolean durable, boolean exclusive, boolean autoDelete,
            Map<String, Object> arguments) {
        Assert.notNull(name, "'name' cannot be null");
        this.name = name;
        this.actualName = StringUtils.hasText(name) ? name
                : (Base64UrlNamingStrategy.DEFAULT.generateName() + "_awaiting_declaration");
        this.durable = durable;
        this.exclusive = exclusive;
        this.autoDelete = autoDelete;
        this.arguments = arguments != null ? arguments : new HashMap<>();
    }

    /**
     * Return the name provided in the constructor.
     * @return the name.
     * @see #getActualName()
     */
    public String getName() {
        return this.name;
    }

    /**
     * A durable queue will survive a server restart.
     *
     * @return true if durable.
     */
    public boolean isDurable() {
        return this.durable;
    }

    /**
     * True if the server should only send messages to the declarer's connection.
     *
     * @return true if exclusive.
     */
    public boolean isExclusive() {
        return this.exclusive;
    }

    /**
     * True if the server should delete the queue when it is no longer in use (the last consumer is cancelled). A queue
     * that never has any consumers will not be deleted automatically.
     *
     * @return true if auto-delete.
     */
    public boolean isAutoDelete() {
        return this.autoDelete;
    }

    public java.util.Map<java.lang.String, java.lang.Object> getArguments() {
        return this.arguments;
    }

    /**
     * Set the name from the DeclareOk.
     * @param name the name.
     * @since 2.1
     */
    public void setActualName(String name) {
        this.actualName = name;
    }

    /**
     * Return the name provided to the constructor or the broker-generated name
     * if that name is an empty String.
     * @return the name.
     * @since 2.1
     */
    public String getActualName() {
        return this.actualName;
    }

    /**
     * Set the master locator strategy argument for this queue.
     * @param locator the locator; null to clear the argument.
     * @since 2.1
     */
    public final void setMasterLocator(@Nullable String locator) {
        if (locator == null) {
            this.arguments.remove(X_QUEUE_MASTER_LOCATOR);
        } else {
            this.arguments.put(X_QUEUE_MASTER_LOCATOR, locator);
        }
    }

    @Override
    public String toString() {
        return "Queue [name=" + this.name + ", durable=" + this.durable + ", autoDelete=" + this.autoDelete
                + ", exclusive=" + this.exclusive + ", arguments=" + this.arguments + ", actualName="
                + this.actualName + "]";
    }

}