1 package org.apache.lucene.queryParser.standard.processors;
4 * Licensed to the Apache Software Foundation (ASF) under one or more
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6 * this work for additional information regarding copyright ownership.
7 * The ASF licenses this file to You under the Apache License, Version 2.0
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20 import java.util.List;
22 import org.apache.lucene.queryParser.core.QueryNodeException;
23 import org.apache.lucene.queryParser.core.nodes.BooleanQueryNode;
24 import org.apache.lucene.queryParser.core.nodes.ModifierQueryNode;
25 import org.apache.lucene.queryParser.core.nodes.QueryNode;
26 import org.apache.lucene.queryParser.core.nodes.ModifierQueryNode.Modifier;
27 import org.apache.lucene.queryParser.core.processors.QueryNodeProcessorImpl;
28 import org.apache.lucene.queryParser.standard.nodes.BooleanModifierNode;
31 * This processor removes every {@link BooleanQueryNode} that contains only one
32 * child and returns this child. If this child is {@link ModifierQueryNode} that
33 * was defined by the user. A modifier is not defined by the user when it's a
34 * {@link BooleanModifierNode} <br/>
36 * @see ModifierQueryNode
38 public class BooleanSingleChildOptimizationQueryNodeProcessor extends
39 QueryNodeProcessorImpl {
41 public BooleanSingleChildOptimizationQueryNodeProcessor() {
46 protected QueryNode postProcessNode(QueryNode node) throws QueryNodeException {
48 if (node instanceof BooleanQueryNode) {
49 List<QueryNode> children = node.getChildren();
51 if (children != null && children.size() == 1) {
52 QueryNode child = children.get(0);
54 if (child instanceof ModifierQueryNode) {
55 ModifierQueryNode modNode = (ModifierQueryNode) child;
57 if (modNode instanceof BooleanModifierNode
58 || modNode.getModifier() == Modifier.MOD_NONE) {
77 protected QueryNode preProcessNode(QueryNode node) throws QueryNodeException {
84 protected List<QueryNode> setChildrenOrder(List<QueryNode> children)
85 throws QueryNodeException {