Is it possible to update more than one field of an issue at once?

[D. U.]

I know that I can update one field of an issue over the REST API, but if I work upon an issue it may be that I edit more than one field. How can I update this issue on the whole. ...or do I have to update each field with a separate REST call to the JIRA API?

[D. U.]

I see...

I have to use a Map. ...maybe this way:

final Map<String, FieldInput> map = new HashMap<String, FieldInput>();
map.put("description", new FieldInput("summary", issue.getSummary() + " --> xxxxxxxxxxxxx"));
final IssueInput newVals = new IssueInput(map);
jiraRestClient.getIssueClient().updateIssue(issueKey, newVals).claim();