View Javadoc
1   /*
2    * Copyright 2001-2008 The Apache Software Foundation.
3    * 
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    * 
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    * 
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   *
16   */
17  
18  package org.apache.juddi.query;
19  
20  import java.util.Collections;
21  import java.util.List;
22  import java.util.UUID;
23  
24  import javax.persistence.EntityManager;
25  
26  import org.apache.commons.configuration.ConfigurationException;
27  import org.apache.commons.logging.Log;
28  import org.apache.commons.logging.LogFactory;
29  import org.apache.juddi.config.AppConfig;
30  import org.apache.juddi.config.Property;
31  import org.apache.juddi.query.util.DynamicQuery;
32  import org.apache.juddi.query.util.FindQualifiers;
33  import org.uddi.v3_service.DispositionReportFaultMessage;
34  import org.uddi.api_v3.ListDescription;
35  
36  /**
37   * The "select" method retrieves all the entities for the input key list and sorts according to the user settings.  Paging is taken into account when retrieving 
38   * the results.  The result is a list of the entity objects containing all top level elements (restricted to the given page). 
39   * 
40   * NOTE:  Results usually need multiple one-to-many collections to be fetched.  Although this could be done in one query with eager fetching, this strategy is not
41   * recommended as it will lead to a potentially large Cartesian product.  Therefore, the collections are initialized in separate queries during the mapping 
42   * stage.  If the returned results are small (maxRows parameters is set appropriately), a single query is likely faster, but probably not by enough to consider 
43   * the optimization under these conditions.
44   * 
45   * @author <a href="mailto:jfaath@apache.org">Jeff Faath</a>
46   */
47  public class FetchBusinessEntitiesQuery extends BusinessEntityQuery {
48  
49  	private static final Log log = LogFactory.getLog(FetchBusinessEntitiesQuery.class);
50  
51  	protected static final String selectSQL;
52  
53  	static {
54  		StringBuilder sql = new StringBuilder(200);
55  		sql.append("select " + ENTITY_ALIAS + " from " + ENTITY_NAME + " " + ENTITY_ALIAS + " ");
56  		selectSQL = sql.toString();
57  	}
58  	
59  	public static List<?> select(EntityManager em, FindQualifiers fq, List<?> keysIn, Integer maxRowsUser, Integer listHead, ListDescription listDesc, DynamicQuery.Parameter... restrictions) throws DispositionReportFaultMessage {
60  		
61  		// If keysIn is null or empty, then nothing to fetch.
62  		if ((keysIn == null) || (keysIn.size() == 0))
63  		return Collections.emptyList();
64  		
65  		int maxRows = DEFAULT_MAXROWS;
66  		try {
67  			maxRows = AppConfig.getConfiguration().getInteger(Property.JUDDI_MAX_ROWS, DEFAULT_MAXROWS);
68  		}
69  		catch(ConfigurationException ce) {
70  			log.error("Configuration exception occurred retrieving: " + Property.JUDDI_MAX_ROWS);
71  		}
72  		DynamicQuery dynamicQry = new DynamicQuery(selectSQL);
73  		if (keysIn.size() > maxRows) {
74  			UUID uuid = UUID.randomUUID();
75  			storeIntermediateKeySetResults(em, uuid.toString(), keysIn);
76  			appendTempTable(dynamicQry);
77  			appendSortTables(dynamicQry);
78  			appendTempJoin(dynamicQry, uuid.toString());
79  		}
80  		else {
81  			appendSortTables(dynamicQry);
82  			dynamicQry.appendInListWithAnd(ENTITY_ALIAS + "." + KEY_NAME, keysIn);
83  		}
84  		if (restrictions != null && restrictions.length > 0)
85  			dynamicQry.AND().pad().appendGroupedAnd(restrictions);
86  
87  		appendSortCriteria(dynamicQry, fq);
88  
89  		log.debug(dynamicQry);
90  		return getPagedResult(em, dynamicQry, maxRowsUser, listHead, listDesc);
91  	}
92  	
93  	private static void appendTempTable(DynamicQuery qry) {
94  		qry.comma().append(TEMP_ENTITY_NAME + " " +  TEMP_ENTITY_ALIAS );
95  	}
96  	
97  	private static void appendTempJoin(DynamicQuery qry, String uuid) {
98  		qry.pad().AND().pad().append(TEMP_ENTITY_PK_KEY_NAME).append(DynamicQuery.PREDICATE_EQUALS);
99  		qry.pad().append(ENTITY_ALIAS + "." + KEY_NAME);
100 		qry.pad().AND().pad().append(TEMP_ENTITY_PK_TXID_NAME).append(DynamicQuery.PREDICATE_EQUALS);
101 		qry.append("'" + uuid + "'").pad();
102 	}
103 	
104 	private static void appendSortTables(DynamicQuery qry) {
105 		qry.pad().comma().pad().append(FindBusinessByNameQuery.ENTITY_NAME_CHILD).pad().append(buildAlias(FindBusinessByNameQuery.ENTITY_NAME_CHILD)).pad();
106 		qry.WHERE().pad().append(ENTITY_ALIAS + "." + KEY_NAME).pad();
107 		qry.append(DynamicQuery.PREDICATE_EQUALS).pad();
108 		qry.append(buildAlias(FindBusinessByNameQuery.ENTITY_NAME_CHILD) + "." + ENTITY_FIELD + "." + KEY_NAME).pad();
109 	}
110 	
111 	/*
112 	 *	Default ordering is name ascending and date descending.  If a name item is set, then it will always go first.  If only a date item is set, then date will
113 	 *  go first, and the name sort will occur second in ascending order.
114 	 */
115 	private static void appendSortCriteria(DynamicQuery qry, FindQualifiers fq) {
116 		
117 		String nameTerm = buildAlias(FindBusinessByNameQuery.ENTITY_NAME_CHILD) + ".name";
118 		
119 		if (fq.isCaseInsensitiveSort()) {
120 			// See JUDDI-785
121 			log.info("jUDDI does not support caseInsensitive sort, as JPA does not support sortBy "
122 					+ "with UPPER or LOWER, see https://issues.apache.org/jira/browse/OPENJPA-1817. "
123 					+ "A work around is to do a caseInsentive Match.");
124 			//nameTerm = "upper(" + nameTerm + ")";
125 		}
126 		
127 		String dateTerm = ENTITY_ALIAS + ".modified";
128 
129 		String orderClause = nameTerm + " " + DynamicQuery.SORT_ASC + ", " + dateTerm + " " + DynamicQuery.SORT_DESC;
130 		if (fq.isSortByNameAsc()) {
131 			if (fq.isSortByDateAsc())
132 				orderClause = nameTerm + " " + DynamicQuery.SORT_ASC + ", " + dateTerm + " " + DynamicQuery.SORT_ASC;
133 		}
134 		else if (fq.isSortByNameDesc()) {
135 			if (fq.isSortByDateAsc())
136 				orderClause = nameTerm + " " + DynamicQuery.SORT_DESC + ", " + dateTerm + " " + DynamicQuery.SORT_ASC;
137 			else
138 				orderClause = nameTerm + " " + DynamicQuery.SORT_DESC + ", " + dateTerm + " " + DynamicQuery.SORT_DESC;
139 		}
140 		else if (fq.isSortByDateAsc())
141 			orderClause =  dateTerm + " " + DynamicQuery.SORT_ASC + ", " +  nameTerm + " " + DynamicQuery.SORT_ASC;
142 		else if (fq.isSortByDateDesc())
143 			orderClause =  dateTerm + " " + DynamicQuery.SORT_DESC + ", " +  nameTerm + " " + DynamicQuery.SORT_ASC;
144 			
145 		qry.ORDERBY().pad();
146 		qry.append(orderClause);
147 		qry.pad();
148 	}
149 
150 }