pylucene 3.5.0-3

[pylucene.git] / lucene-java-3.5.0 / lucene / contrib / queryparser / src / java / org / apache / lucene / queryParser / core / nodes / SlopQueryNode.java

diff --git a/lucene-java-3.5.0/lucene/contrib/queryparser/src/java/org/apache/lucene/queryParser/core/nodes/SlopQueryNode.java b/lucene-java-3.5.0/lucene/contrib/queryparser/src/java/org/apache/lucene/queryParser/core/nodes/SlopQueryNode.java
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+++ b/lucene-java-3.5.0/lucene/contrib/queryparser/src/java/org/apache/lucene/queryParser/core/nodes/SlopQueryNode.java
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+package org.apache.lucene.queryParser.core.nodes;
+
+/**
+ * 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 org.apache.lucene.messages.MessageImpl;
+import org.apache.lucene.queryParser.core.QueryNodeError;
+import org.apache.lucene.queryParser.core.messages.QueryParserMessages;
+import org.apache.lucene.queryParser.core.parser.EscapeQuerySyntax;
+
+/**
+ * A {@link SlopQueryNode} represents phrase query with a slop.
+ * 
+ * From Lucene FAQ: Is there a way to use a proximity operator (like near or
+ * within) with Lucene? There is a variable called slop that allows you to
+ * perform NEAR/WITHIN-like queries. By default, slop is set to 0 so that only
+ * exact phrases will match. When using TextParser you can use this syntax to
+ * specify the slop: "doug cutting"~2 will find documents that contain
+ * "doug cutting" as well as ones that contain "cutting doug".
+ */
+public class SlopQueryNode extends QueryNodeImpl implements FieldableNode {
+
+  private static final long serialVersionUID = 0L;
+
+  private int value = 0;
+
+  /**
+   * @param query
+   *          - QueryNode Tree with the phrase
+   * @param value
+   *          - slop value
+   */
+  public SlopQueryNode(QueryNode query, int value) {
+    if (query == null) {
+      throw new QueryNodeError(new MessageImpl(
+          QueryParserMessages.NODE_ACTION_NOT_SUPPORTED, "query", "null"));
+    }
+
+    this.value = value;
+    setLeaf(false);
+    allocate();
+    add(query);
+  }
+
+  public QueryNode getChild() {
+    return getChildren().get(0);
+  }
+
+  public int getValue() {
+    return this.value;
+  }
+
+  private CharSequence getValueString() {
+    Float f = Float.valueOf(this.value);
+    if (f == f.longValue())
+      return "" + f.longValue();
+    else
+      return "" + f;
+
+  }
+
+  @Override
+  public String toString() {
+    return "<slop value='" + getValueString() + "'>" + "\n"
+        + getChild().toString() + "\n</slop>";
+  }
+
+  public CharSequence toQueryString(EscapeQuerySyntax escapeSyntaxParser) {
+    if (getChild() == null)
+      return "";
+    return getChild().toQueryString(escapeSyntaxParser) + "~"
+        + getValueString();
+  }
+
+  @Override
+  public QueryNode cloneTree() throws CloneNotSupportedException {
+    SlopQueryNode clone = (SlopQueryNode) super.cloneTree();
+
+    clone.value = this.value;
+
+    return clone;
+  }
+
+  public CharSequence getField() {
+    QueryNode child = getChild();
+
+    if (child instanceof FieldableNode) {
+      return ((FieldableNode) child).getField();
+    }
+
+    return null;
+
+  }
+
+  public void setField(CharSequence fieldName) {
+    QueryNode child = getChild();
+
+    if (child instanceof FieldableNode) {
+      ((FieldableNode) child).setField(fieldName);
+    }
+
+  }
+
+}