static String constructJQLQuery( Collection<String> issueKeys) {
        StringBuilder jql = new StringBuilder();
        jql.append("key in (");
        Iterator<String> iterator = issueKeys.iterator();
        while ( iterator.hasNext() ) {
            String key = iterator.next();
            jql.append("'");
            jql.append(key);
            jql.append("'");
            if (iterator.hasNext()) {
                jql.append(",");
            }
        }
        jql.append(")");
        return jql.toString();
    }
@Test
    public void constructJQLQuery() throws Exception {
        Assert.assertEquals("key in ('JENKINS-123')",
                            JiraSCMListener.constructJQLQuery(Collections.singletonList("JENKINS-123")));
        Assert.assertEquals("key in ('JENKINS-123','FOO-123','VIVEK-123')",
                            JiraSCMListener.constructJQLQuery( Arrays.asList("JENKINS-123", "FOO-123", "VIVEK-123")));
    }