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.schema; 016 017 import java.util.List; 018 019 import org.apache.hivemind.Locatable; 020 import org.apache.hivemind.internal.Module; 021 import org.apache.hivemind.parse.AnnotationHolder; 022 023 /** 024 * An object which may contain a model, used to identify the form of XML content allowed within some 025 * other, containing element. 026 * <p> 027 * This is very much provisional; in the future will be more control for validation (i.e, 028 * controlling the number of occurances), and support for analogs of W3C SChema sequence and choice. 029 * The excess flexibility here forces some validation into element objects (the objects created from 030 * the {@link org.apache.hivemind.schema.Rule}s within the 031 * {@link org.apache.hivemind.schema.ElementModel}s). 032 * 033 * @author Howard Lewis Ship 034 */ 035 public interface Schema extends AnnotationHolder, Locatable 036 { 037 /** 038 * Returns the (unqualified) id of this schema. 039 * 040 * @since 1.1 041 */ 042 public String getId(); 043 044 /** 045 * Returns a List of {@link ElementModel}, identifing the elements which may be enclosed by the 046 * modeled element. 047 * <p> 048 * The returned list is unmodifiabled and may be empty, but won't be null. 049 */ 050 public List getElementModel(); 051 052 /** 053 * Returns true if Elements conforming to this Schema can be indexed using a key. For this to be 054 * true every {@link #getElementModel() top-level ElementModel} must define a non-null 055 * {@link ElementModel#getKeyAttribute() key attribute}. 056 * 057 * @since 1.1 058 */ 059 public boolean canInstancesBeKeyed(); 060 061 /** 062 * Returns true if the schema is visible to the specified module, false otherwise. 063 * 064 * @since 1.1 065 */ 066 public boolean visibleToModule(String moduleId); 067 068 /** 069 * 070 * Return the Module in which the Schema was defined. 071 * 072 * @since 1.1 073 * 074 */ 075 076 public Module getDefiningModule(); 077 }