How to update a field in issue with Jira rest java client?

I try to update priority for an issue. I use jrjc version 5.1.0

IssueRestClient issueClient = restClient.getIssueClient();
IssueInput issueInput= .... 
issueClient.updateIssue(issueKey,issueInput);

I find the function with have 2 param issueKey and issue.

But I just want to update one field. How can I do that?

Thank you,

Just do like this :wink:

I

IssueRestClient issueClient = restClient.getIssueClient();

IssueInputBuilder builder = new IssueInputBuilder();
builder.setPriorityId(priorityChangeId);

IssueInput issueInput= builder.build()
issueClient.updateIssue(issueKey,issueInput);