Could not connect to broker URL: tcp://localhost:61616.
在学习JMS的时候遇到了这个了问题，问题如下：
严重: Servlet.service() for servlet [action] in context with path [/WechatDemo] threw exception [Request processing failed; nested exception is org.springframework.jms.UncategorizedJmsException: Uncategorized exception occurred during JMS processing; nested exception is javax.jms.JMSException: Could not connect to broker URL: tcp://localhost:61616. Reason: java.net.ConnectException: Connection refused: connect] with root cause
java.net.ConnectException: Connection refused: connect
at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at org.apache.activemq.transport.tcp.TcpTransport.connect(TcpTransport.java:525)
at org.apache.activemq.transport.tcp.TcpTransport.doStart(TcpTransport.java:488)
at org.apache.activemq.util.ServiceSupport.start(ServiceSupport.java:55)
at org.apache.activemq.transport.AbstractInactivityMonitor.start(AbstractInactivityMonitor.java:169)
at org.apache.activemq.transport.InactivityMonitor.start(InactivityMonitor.java:52)
at org.apache.activemq.transport.TransportFilter.start(TransportFilter.java:64)
at org.apache.activemq.transport.WireFormatNegotiator.start(WireFormatNegotiator.java:72)
at org.apache.activemq.transport.TransportFilter.start(TransportFilter.java:64)
at org.apache.activemq.transport.TransportFilter.start(TransportFilter.java:64)
at org.apache.activemq.ActiveMQConnectionFactory.createActiveMQConnection(ActiveMQConnectionFactory.java:354)
at org.apache.activemq.ActiveMQConnectionFactory.createActiveMQConnection(ActiveMQConnectionFactory.java:304)
at org.apache.activemq.ActiveMQConnectionFactory.createConnection(ActiveMQConnectionFactory.java:244)
at org.springframework.jms.support.JmsAccessor.createConnection(JmsAccessor.java:180)
at org.springframework.jms.core.JmsTemplate.execute(JmsTemplate.java:474)
at org.springframework.jms.core.JmsTemplate.send(JmsTemplate.java:570)
at org.springframework.jms.core.JmsTemplate.convertAndSend(JmsTemplate.java:658)
at org.springframework.jms.core.JmsTemplate.convertAndSend(JmsTemplate.java:642)
at com.cmcc.service.impl.AlertServiceImpl.sendUserAlert(AlertServiceImpl.java:39)
at com.cmcc.controller.JMSMessageController.sendMessage(JMSMessageController.java:25)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:114)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:94)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:492)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:620)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:502)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1152)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:684)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2527)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2516)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
问题原因：ObjectMessage对象依赖于marshal / unmarshal对象有效负载的Java序列化。由于恶意有效负载可以利用主机系统，因此通常认为此过程不安全。这就是为什么从版本5.12.2和 5.13.0开始，ActiveMQ强制用户明确地将可以使用ObjectMessages交换的包列入白名单。
解决方案：
要么设置白名单
org.apache.activemq.test
org.apache.camel.test
要么全部添加信任
这里附上官网给出的解释点这里