How do I save a value into a custom field in JIRA programmatically?

Question

I\'ve spent days trying to find out how to save or update a value into a CustomField programmatically and finally found out how it\'s done. So I\'ll make this a question an

Answer 1

Here is how I do it (for a custom field I programmatically store a random UUID in):

CustomField cfHash = customFieldManager.getCustomFieldObjectByName(...);
IssueChangeHolder changeHolder = new DefaultIssueChangeHolder();
try {
    Object newHashValue = java.util.UUID.randomUUID().toString();
    Object oldHashValue = issue.getCustomFieldValue(cfHash);

    issue.setCustomFieldValue(cfHash, newHashValue);
    cfHash.updateValue(null, issue, new ModifiedValue(oldHashValue, newHashValue), changeHolder);
...

More or less the same as you but with another way to get the ModifiedValue-Object.