When you create a script (Groovy or BeanShell), for example in a condition for a post-function or in a Calculated Field, you can use
issue.get(<field_name>) to get the value of an Issue field, where
<field_name> can be either the name of a JIRA standard field or the internal name of a custom field.
In the case of a custom field,
<field_name> has the form
customfield_xxxxx, where xxxxx is the custom field numerical ID, as seen in the URL when editing the field. Or, starting with JIRA Misc Custom Fields v1.6.2 or JIRA Misc Workflow Extensions v. 3.7.0, you can also use the "real name" of the custom field (as shown in the list of custom fields).
The type of the return value of issue.get(...) depends on the type of the custom field you are accessing. The following table shows the return type for standard custom field types (provided by JIRA):
A lot more custom field types might be available on your JIRA instance, based on the plugins you have installed. The following table shows the return type for the most common "advanced" custom field types:
In the case of standard fields,
<field_name> can be one of the following strings:
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