1 /******************************************************************************* 2 * Copyright (c) 2011 Google, Inc. 3 * All rights reserved. This program and the accompanying materials 4 * are made available under the terms of the Eclipse Public License v1.0 5 * which accompanies this distribution, and is available at 6 * http://www.eclipse.org/legal/epl-v10.html 7 * 8 * Contributors: 9 * Google, Inc. - initial API and implementation 10 *******************************************************************************/ 11 package org.eclipse.wb.internal.core.model.property.category; 12 13 import org.eclipse.wb.internal.core.model.property.Property; 14 import org.eclipse.wb.internal.core.model.property.PropertyManager; 15 16 /** 17 * Factory for {@link PropertyCategoryProvider} instances. 18 * 19 * @author scheglov_ke 20 * @coverage core.model.property 21 */ 22 public final class PropertyCategoryProviders { 23 //////////////////////////////////////////////////////////////////////////// 24 // 25 // Simple providers 26 // 27 //////////////////////////////////////////////////////////////////////////// 28 private static final PropertyCategoryProvider FROM_PROPERTY = new PropertyCategoryProvider() { 29 public PropertyCategory getCategory(Property property) { 30 return property.getCategory(); 31 } 32 }; 33 34 /** 35 * Returns result of {@link Property#getCategory()}, never <code>null</code>. 36 */ fromProperty()37 public static PropertyCategoryProvider fromProperty() { 38 return FROM_PROPERTY; 39 } 40 41 private static final PropertyCategoryProvider FORCED_BY_USER = new PropertyCategoryProvider() { 42 public PropertyCategory getCategory(Property property) { 43 return PropertyManager.getCategoryForced(property); 44 } 45 }; 46 47 /** 48 * Returns category forced by user, may be <code>null</code>. 49 */ forcedByUser()50 public static PropertyCategoryProvider forcedByUser() { 51 return FORCED_BY_USER; 52 } 53 54 //////////////////////////////////////////////////////////////////////////// 55 // 56 // Compound 57 // 58 //////////////////////////////////////////////////////////////////////////// 59 /** 60 * Returns first not <code>null</code> category returned by provider. 61 */ combine(final PropertyCategoryProvider... providers)62 public static PropertyCategoryProvider combine(final PropertyCategoryProvider... providers) { 63 return new PropertyCategoryProvider() { 64 public PropertyCategory getCategory(Property property) { 65 for (PropertyCategoryProvider provider : providers) { 66 PropertyCategory category = provider.getCategory(property); 67 if (category != null) { 68 return category; 69 } 70 } 71 throw new IllegalStateException("Can not provide category for " + property.getTitle()); 72 } 73 }; 74 } 75 76 private static final PropertyCategoryProvider DEF = combine(forcedByUser(), fromProperty()); 77 78 /** 79 * Returns the default combination of {@link PropertyCategoryProvider}s - first 80 * {@link #forcedByUser()}, then {@link #fromProperty()}. 81 */ 82 public static PropertyCategoryProvider def() { 83 return DEF; 84 } 85 } 86