RabbitMq不支持修改已经存在的队列和交换机参数，可以通过创建失败，捕获异常信息，然后删除原队列或交换机，然后重新创建，以达到修改参数的功能。

package com.sky.study.delete;

import java.io.IOException;

import java.util.concurrent.TimeoutException;

import com.rabbitmq.client.AMQP;

import com.rabbitmq.client.AMQP.Queue.DeclareOk;

import com.rabbitmq.client.Channel;

import com.rabbitmq.client.Connection;

import com.sky.study.ConnectionUtil;

public class DynamicDelete {

private final static String queueName="ceshi_queue";

public static void main(String[] args) throws Exception {

Connection connection = ConnectionUtil.getConnection();

Channel channel = connection.createChannel();

DeclareOk ss = declearQueue(channel,queueName);

System.out.println(ss);

channel.close();

connection.close();

}

public static DeclareOk declearQueue(Channel channel, String queueName) throws Exception {

Connection connection1 = ConnectionUtil.getConnection();

Channel channel1 = connection1.createChannel();

try {

channel1.queueDeclare(queueName,true, false, false, null);

} catch (IOException e) {

try {

channel1.close();

} catch (Exception ex) {

}

try {

connection1.close();

} catch (Exception ex) {

}

connection1 = ConnectionUtil.getConnection();

channel1 = connection1.createChannel();

channel1.queueDelete(queueName);

try {

channel1.close();

} catch (Exception ex) {

}

try {

connection1.close();

} catch (Exception ex) {

}

} finally {

try {

channel1.close();

} catch (Exception ex) {

}

try {

connection1.close();

} catch (Exception ex) {

}

}

DeclareOk declareOk = channel.queueDeclare(queueName, true, false, false, null);

return declareOk;

}

public static AMQP.Exchange.DeclareOk declearExchange(Channel channel, String exchangeName, String exchangeMode) throws IOException, TimeoutException {

//exchangeDeclare 交换机名字，类型，是否持久化，不使用时是否自动删除，是否是内部的(不能被客户端使用)，其他参数

Connection connection1 = ConnectionUtil.getConnection();

Channel channel1 = connection1.createChannel();

AMQP.Exchange.DeclareOk declareOk;

try {

channel1.exchangeDeclare(exchangeName, exchangeMode, true, false, false, null);

} catch (IOException e) {

try {

channel1.close();

} catch (Exception ex) {

}

try {

connection1.close();

} catch (Exception ex) {

}

connection1 = ConnectionUtil.getConnection();

channel1 = connection1.createChannel();

channel1.exchangeDelete(exchangeName);

try {

channel1.close();

} catch (Exception ex) {

}

try {

connection1.close();

} catch (Exception ex) {

}

} finally {

try {

channel1.close();

} catch (Exception ex) {

}

try {

connection1.close();

} catch (Exception ex) {

}

}

declareOk = channel.exchangeDeclare(exchangeName, exchangeMode,true, false, false, null);

return declareOk;

}

}