To sort in Java, you must compare elements that are Comparable
or create an external Comparator.
By creating a Comparator or implementing
Comparable, we gain full control of the sort
order of our elements.
For the Issue class, you can sort using the
priority field:
import java.util.Comparator; // a simple issues library import ca.odell.issuezilla.*; /** * Compare issues by priority. * * @author <a href="mailto:jesse@odel.on.ca">Jesse Wilson</a> */ public class IssueComparator implements Comparator { public int compare(Object a, Object b) { Issue issueA = (Issue)a; Issue issueB = (Issue)b; // rating is between 1 and 5, lower is more important int issueAValue = issueA.getPriority().getValue(); int issueBValue = issueB.getPriority().getValue(); return issueAValue - issueBValue; } }
Now that you can compare elements, create a
SortedList using the issues
EventList and the
IssueComparator. The
SortedList will provide a sorted view of the
issues list. It keeps the issues sorted dynamically as the source
EventList changes.
SortedList sortedIssues = new SortedList(issuesEventList, new IssueComparator());