问题
We are using Active MQ in the most current version 5.6.0. Now we have the problem that a new client has to be connected, unfortunately this client is developed with IBM JDK 1.4. Adding ActiveMQ to the application lead to the following error:
UNEXPECTED ERROR OCCURRED: org/apache/activemq/ActiveMQConnectionFactory (Unsupported major.minor version 50.0)
STACK TRACE:
java.lang.UnsupportedClassVersionError: org/apache/activemq/ActiveMQConnectionFactory (Unsupported major.minor version 50.0)
We don't want to switch to an older ActiveMQ version, since there are other applications using the current version. Now my questions (I know the FAQ and especially http://activemq.apache.org/can-i-use-activemq-5x-or-later-on-java-14.html):
Are there any ActiveMQ client jars which are usable to connect to Active MQ 5.6.0? For example is it possible to use an ActiveMQ 4.0 client to connect to Active MQ 5.6.0? Is it possible to use any other protocol for this purpose? Has anyone a succesful solution running?
If I have to use retrotranslator which is the minimum set on jars I have to translate? Has anyone the experience with IBM JDK 1.4?
Thanks for your answers!
回答1:
You can connect from STOMP to the ActiveMQ broker, or you can use an older AMQ 5.x client and connect. You can of course try an older 4.x client but its not really recommended. Version 5 clients should be able to connect without much problem however anytime you use an older client you are subject to the issues that are contained in those clients that were fixed in newer releases.
回答2:
You might try to build ActiveMQ yourself (or STOMP), from source, using the -target 1.4 command line option, and addressing other cross-compile concerns. Since you have 1.4 libraries available, you should be able to use those in the bootclasspath for the cross-compile.
Cross your fingers, and you may get lucky by not having any hard dependencies on new library elements (nio). Or you might find ways to work around them.
来源：https://stackoverflow.com/questions/11609062/activemq-client-on-java-1-4