Error connecting to Jira v7.13.1 server from Java6 application with Jira Rest Java Client(JRJC)


I have a requirement to create an Issue in Jira on click of a submit button in java web application. Unfortunately this is very old application and running on IBM Web sphere 7 & Java 6. I need to connect to Jira v7.13.1 version and create an issue, I tried using jira-rest-java-client-api-2.0.0-m32.w1 and getting the following exception. can someone please help me to understand the java version compatibilities between JRJC api & Jira server.

code snippet:
final AsynchronousJiraRestClientFactory factory = new AsynchronousJiraRestClientFactory();
final URI uri = new URI(“http://localhost:8080/”);
final JiraRestClient jiraRestClient = factory.createWithBasicHttpAuthentication(uri, “abcd”, “1234”);

    IssueInputBuilder issueInputBuilder = new IssueInputBuilder("DEMO", 10003L, "Test Summary");
    issueInputBuilder.setDescription("Test Description");
    IssueInput issueInput =;
    Promise<BasicIssue> createdIssue= jiraRestClient.getIssueClient().createIssue(issueInput);
    try {
		BasicIssue basicIssue= createdIssue.get();
		System.out.println("Issue Key: "+basicIssue.getKey());
	} catch (ExecutionException e) {
		// TODO Auto-generated catch block

Exception in thread “main” java.lang.UnsupportedClassVersionError: JVMCFRE003 bad major version; class=com/atlassian/jira/rest/client/internal/async/AsynchronousJiraRestClientFactory, offset=6
at java.lang.ClassLoader.defineClassImpl(Native Method)
at java.lang.ClassLoader.defineClass(


@malikasweet - JRJC supports any Jira Server version >= 4.2. If you’re using a binary (Maven artifact), perhaps you should try building from source.

Thank you very much for quick response. Do you mean with any version of JRJC jar we can I connect to Jira server version >= 4.2 ?
I am wondering what’s the best jira-rest-java-client-api version for JDK 1.6
First I used 2.0.0-m32 version but it didn’t worked, now I am trying to use 1.0 version.
My web project is not Maven project so I am trying to download all the jar files and add to class path, please suggest me if we have some link to download all the dependent jars for JRJC version 1.0.