--- /dev/null
+package org.apache.lucene.queryParser.standard.processors;
+
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.lucene.queryParser.core.QueryNodeException;
+import org.apache.lucene.queryParser.core.config.QueryConfigHandler;
+import org.apache.lucene.queryParser.core.nodes.AndQueryNode;
+import org.apache.lucene.queryParser.core.nodes.BooleanQueryNode;
+import org.apache.lucene.queryParser.core.nodes.GroupQueryNode;
+import org.apache.lucene.queryParser.core.nodes.ModifierQueryNode;
+import org.apache.lucene.queryParser.core.nodes.OrQueryNode;
+import org.apache.lucene.queryParser.core.nodes.QueryNode;
+import org.apache.lucene.queryParser.core.nodes.ModifierQueryNode.Modifier;
+import org.apache.lucene.queryParser.core.parser.SyntaxParser;
+import org.apache.lucene.queryParser.core.processors.QueryNodeProcessor;
+import org.apache.lucene.queryParser.standard.config.StandardQueryConfigHandler;
+import org.apache.lucene.queryParser.standard.config.StandardQueryConfigHandler.ConfigurationKeys;
+import org.apache.lucene.queryParser.standard.config.StandardQueryConfigHandler.Operator;
+import org.apache.lucene.queryParser.standard.nodes.BooleanModifierNode;
+
+/**
+ * The {@link SyntaxParser}
+ * generates query node trees that consider the boolean operator precedence, but
+ * Lucene current syntax does not support boolean precedence, so this processor
+ * remove all the precedence and apply the equivalent modifier according to the
+ * boolean operation defined on an specific query node. <br/>
+ * <br/>
+ * If there is a {@link GroupQueryNode} in the query node tree, the query node
+ * tree is not merged with the one above it.
+ *
+ * Example: TODO: describe a good example to show how this processor works
+ *
+ * @see org.apache.lucene.queryParser.standard.config.StandardQueryConfigHandler
+ */
+public class GroupQueryNodeProcessor implements QueryNodeProcessor {
+
+ private ArrayList<QueryNode> queryNodeList;
+
+ private boolean latestNodeVerified;
+
+ private QueryConfigHandler queryConfig;
+
+ private Boolean usingAnd = false;
+
+ public GroupQueryNodeProcessor() {
+ // empty constructor
+ }
+
+ public QueryNode process(QueryNode queryTree) throws QueryNodeException {
+ Operator defaultOperator = getQueryConfigHandler().get(ConfigurationKeys.DEFAULT_OPERATOR);
+
+ if (defaultOperator == null) {
+ throw new IllegalArgumentException(
+ "DEFAULT_OPERATOR should be set on the QueryConfigHandler");
+ }
+
+ this.usingAnd = StandardQueryConfigHandler.Operator.AND == defaultOperator;
+
+ if (queryTree instanceof GroupQueryNode) {
+ queryTree = ((GroupQueryNode) queryTree).getChild();
+ }
+
+ this.queryNodeList = new ArrayList<QueryNode>();
+ this.latestNodeVerified = false;
+ readTree(queryTree);
+
+ List<QueryNode> actualQueryNodeList = this.queryNodeList;
+
+ for (int i = 0; i < actualQueryNodeList.size(); i++) {
+ QueryNode node = actualQueryNodeList.get(i);
+
+ if (node instanceof GroupQueryNode) {
+ actualQueryNodeList.set(i, process(node));
+ }
+
+ }
+
+ this.usingAnd = false;
+
+ if (queryTree instanceof BooleanQueryNode) {
+ queryTree.set(actualQueryNodeList);
+
+ return queryTree;
+
+ } else {
+ return new BooleanQueryNode(actualQueryNodeList);
+ }
+
+ }
+
+ /**
+ */
+ private QueryNode applyModifier(QueryNode node, QueryNode parent) {
+
+ if (this.usingAnd) {
+
+ if (parent instanceof OrQueryNode) {
+
+ if (node instanceof ModifierQueryNode) {
+
+ ModifierQueryNode modNode = (ModifierQueryNode) node;
+
+ if (modNode.getModifier() == Modifier.MOD_REQ) {
+ return modNode.getChild();
+ }
+
+ }
+
+ } else {
+
+ if (node instanceof ModifierQueryNode) {
+
+ ModifierQueryNode modNode = (ModifierQueryNode) node;
+
+ if (modNode.getModifier() == Modifier.MOD_NONE) {
+ return new BooleanModifierNode(modNode.getChild(), Modifier.MOD_REQ);
+ }
+
+ } else {
+ return new BooleanModifierNode(node, Modifier.MOD_REQ);
+ }
+
+ }
+
+ } else {
+
+ if (node.getParent() instanceof AndQueryNode) {
+
+ if (node instanceof ModifierQueryNode) {
+
+ ModifierQueryNode modNode = (ModifierQueryNode) node;
+
+ if (modNode.getModifier() == Modifier.MOD_NONE) {
+ return new BooleanModifierNode(modNode.getChild(), Modifier.MOD_REQ);
+ }
+
+ } else {
+ return new BooleanModifierNode(node, Modifier.MOD_REQ);
+ }
+
+ }
+
+ }
+
+ return node;
+
+ }
+
+ private void readTree(QueryNode node) {
+
+ if (node instanceof BooleanQueryNode) {
+ List<QueryNode> children = node.getChildren();
+
+ if (children != null && children.size() > 0) {
+
+ for (int i = 0; i < children.size() - 1; i++) {
+ readTree(children.get(i));
+ }
+
+ processNode(node);
+ readTree(children.get(children.size() - 1));
+
+ } else {
+ processNode(node);
+ }
+
+ } else {
+ processNode(node);
+ }
+
+ }
+
+ private void processNode(QueryNode node) {
+
+ if (node instanceof AndQueryNode || node instanceof OrQueryNode) {
+
+ if (!this.latestNodeVerified && !this.queryNodeList.isEmpty()) {
+ this.queryNodeList.add(applyModifier(this.queryNodeList
+ .remove(this.queryNodeList.size() - 1), node));
+ this.latestNodeVerified = true;
+
+ }
+
+ } else if (!(node instanceof BooleanQueryNode)) {
+ this.queryNodeList.add(applyModifier(node, node.getParent()));
+ this.latestNodeVerified = false;
+
+ }
+
+ }
+
+ public QueryConfigHandler getQueryConfigHandler() {
+ return this.queryConfig;
+ }
+
+ public void setQueryConfigHandler(QueryConfigHandler queryConfigHandler) {
+ this.queryConfig = queryConfigHandler;
+ }
+
+}
fnp / pylucene.git / blobdiff