1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the "License"); 7 * you may not use this file except in compliance with the License. 8 * You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 /* 19 * $Id: ExpressionNode.java 468655 2006-10-28 07:12:06Z minchau $ 20 */ 21 package org.apache.xpath; 22 23 import javax.xml.transform.SourceLocator; 24 25 /** 26 * A class that implements this interface can construct expressions, 27 * give information about child and parent expressions, 28 * and give the originating source information. A class that implements 29 * this interface does not lay any claim to being directly executable. 30 * 31 * <p>Note: This interface should not be considered stable. Only exprSetParent 32 * and exprGetParent can be counted on to work reliably. Work in progress.</p> 33 */ 34 public interface ExpressionNode extends SourceLocator 35 { 36 /** This pair of methods are used to inform the node of its 37 parent. */ 38 public void exprSetParent(ExpressionNode n); 39 public ExpressionNode exprGetParent(); 40 41 /** This method tells the node to add its argument to the node's 42 list of children. */ 43 public void exprAddChild(ExpressionNode n, int i); 44 45 /** This method returns a child node. The children are numbered 46 from zero, left to right. */ 47 public ExpressionNode exprGetChild(int i); 48 49 /** Return the number of children the node has. */ 50 public int exprGetNumChildren(); 51 } 52 53
