001 // Copyright 2004, 2005 The Apache Software Foundation 002 // 003 // Licensed under the Apache License, Version 2.0 (the "License"); 004 // you may not use this file except in compliance with the License. 005 // You may obtain a copy of the License at 006 // 007 // http://www.apache.org/licenses/LICENSE-2.0 008 // 009 // Unless required by applicable law or agreed to in writing, software 010 // distributed under the License is distributed on an "AS IS" BASIS, 011 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012 // See the License for the specific language governing permissions and 013 // limitations under the License. 014 015 package org.apache.hivemind; 016 017 import java.util.List; 018 019 020 /** 021 * Simplified read-only thread safe DOM. 022 * Currently, no support for namespaces, but that may come. 023 * 024 * @author Howard Lewis Ship 025 */ 026 public interface Element extends Locatable 027 { 028 /** 029 * Returns the name of the element, as in, the name of the tag for the element. 030 */ 031 public String getElementName(); 032 033 /** 034 * Returns an unmodifiable list of {@link Attribute} for this element. 035 * May return an empty list, but won't return null. The attributes 036 * are in no specific order. 037 */ 038 public List getAttributes(); 039 040 /** 041 * Returns the value for an attribute, or null if the attribute is not specified. 042 */ 043 044 public String getAttributeValue(String attributeName); 045 046 /** 047 * Returns true if this element contains no other elements. 048 */ 049 public boolean isEmpty(); 050 051 /** 052 * Returns an unmodifiable list of {@link Element} directly contained 053 * by this element. May return an empty list, but won't return null. 054 * The elements are returned in the order in which they were encountered 055 * in the XML. 056 */ 057 public List getElements(); 058 059 /** 060 * Returns the content of the element. This is a concatination of 061 * all the text directly enclosed by the element. Ignorable whitespace 062 * is ignored. The content is trimmed of leading and trailing whitespace. 063 */ 064 065 public String getContent(); 066 }