issue.getField() returns null

[wonder wolf]

I'm trying to get a value from a specific field that determines at runtime. I was trying to check for fields by calling issue.getFields(), but it still returns null. The only one kind of method that returns value properly - method with specified in advance field (example:
issue.getSummary();)
Main method

JiraRestClient restClient = getJiraRestClient(); \\custom method for connecting in jira local server
SearchRestClient searchClient = restClient.getSearchClient();
SearchResult searchResult = searchClient.searchJql(jql, -1, 0, fields).claim();
JsonArrayBuilder issueArrayBuilder = Json.createArrayBuilder();
for (Issue issue : searchResult.getIssues()) {
    Issue initIssue = restClient.getIssueClient().getIssue(issue.getKey()).claim();
    JsonObjectBuilder jsonIssueBuilder = Json.createObjectBuilder();
    for (String field : fields) {
        JsonValue jsonValue = getJsonValueForField(initIssue, field);
        jsonIssueBuilder.add(field, jsonValue);
    }
    JsonObject jsonIssue = jsonIssueBuilder.build();
    issueArrayBuilder.add(jsonIssue);
}
return issueArrayBuilder.build();

private static JsonValue getJsonValueForField(Issue issue, String field) {
    IssueField issueField = issue.getField(field);

[Hauke Bruno Wollentin]

The Issue interface does not provide a method called "getField()" (see https://docs.atlassian.com/software/jira/docs/api/9.10.0/com/atlassian/jira/issue/Issue.html )

To fetch the value of a custom field you need to get the custom field as CustomField object and use the "getCustomFieldValue()" method of the actual Issue then.

For instance:

import com.atlassian.jira.issue.fields.CustomField
import com.atlassian.jira.issue.CustomFieldManager
import com.atlassian.jira.component.ComponentAccessor

CustomFieldManager cfManager = ComponentAccessor.getCustomFieldManager()

CustomField customFieldObject = cfManager.getCustomFieldObjectsByName("Foo").first()

def customFieldValueOfIssue = issue.getCustomFieldValue(customFieldObject)

There is also an interface FieldManager available to work with fields in a generic way.