[LUCENE-2146] DisjunctionMaxQuery has incorrect hashCode() implementation

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Invalid
• Affects Version/s: 2.9
• Component/s: core/search
• Lucene Fields: New, Patch Available
• Assignee: Unassigned
• Reporter: wang
• Created: 11/Dec/09 03:52
• Updated: 28/Aug/22 12:16
• Resolved: 14/Dec/09 13:09

Description

The DisjunctionMaxQuery class hashCode() implementation is non-deterministic. It uses disjuncts.hashCode() in the computation.
if the contents of disjuncts are arrays, just as DisjunctionMaxQueryTest.
ArrayList list1 = new ArrayList();
ArrayList list2 = new ArrayList();
String[] terms =

{"term1","term2"};
String[] terms2 ={"term1","term2"}

;
list1.add(terms);
list2.add(terms2);
DisjunctionMaxQuery query1 = new DisjunctionMaxQuery(list1,0.0f);
DisjunctionMaxQuery query2 = new DisjunctionMaxQuery(list2,0.0f);
according to the definition of DisjunctionMaxQuery, i think query1 and query2 should be equal.
but DisjunctionMaxQueryTest failed. That is because of DisjunctionMaxQuery.hashCode()

{disjuncts.hasCode()}

;
maybe my thought is wrong.