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1
56
57 package org.objectstyle.cayenne.dba.db2;
58
59 import java.sql.Connection  ;
60 import java.sql.ResultSet ;
61 import java.sql.SQLException ;
62 import java.sql.Statement ;
63 import java.util.ArrayList ;
64 import java.util.Collections ;
65 import java.util.Iterator ;
66 import java.util.List ;
67
68 import org.objectstyle.cayenne.CayenneRuntimeException;
69 import org.objectstyle.cayenne.access.DataNode;
70 import org.objectstyle.cayenne.access.QueryLogger;
71 import org.objectstyle.cayenne.dba.JdbcPkGenerator;
72 import org.objectstyle.cayenne.map.DbEntity;
73
74
79 public class DB2PkGenerator extends JdbcPkGenerator {
80
81 public static final String SEQUENCE_PREFIX = "S_";
82
83 public void createAutoPk(DataNode node, List dbEntities) throws Exception {
84 List sequences = this.getExistingSequences(node);
85 Iterator it = dbEntities.iterator();
86
87 while (it.hasNext()) {
88 DbEntity ent = (DbEntity) it.next();
89 if (!sequences.contains(sequenceName(ent))) {
90 this.runUpdate(node, this.createSequenceString(ent));
91 }
92 }
93 }
94
95 public List createAutoPkStatements(List dbEntities) {
96 List list = new ArrayList ();
97 Iterator it = dbEntities.iterator();
98
99 while (it.hasNext()) {
100 DbEntity ent = (DbEntity) it.next();
101 list.add(this.createSequenceString(ent));
102 }
103
104 return list;
105 }
106
107 public void dropAutoPk(DataNode node, List dbEntities) throws Exception {
108 List sequences = this.getExistingSequences(node);
109
110 Iterator it = dbEntities.iterator();
111 while (it.hasNext()) {
112 DbEntity ent = (DbEntity) it.next();
113 if (sequences.contains(this.sequenceName(ent))) {
114 this.runUpdate(node, this.dropSequenceString(ent));
115 }
116 }
117 }
118
119 public List dropAutoPkStatements(List dbEntities) {
120 List list = new ArrayList ();
121 Iterator it = dbEntities.iterator();
122
123 while (it.hasNext()) {
124 DbEntity ent = (DbEntity) it.next();
125 list.add(this.dropSequenceString(ent));
126 }
127
128 return list;
129 }
130
131
134 protected String sequenceName(DbEntity ent) {
135 String seqName = SEQUENCE_PREFIX + ent.getName();
136
137 if (ent.getSchema() != null && ent.getSchema().length() > 0) {
138 seqName = ent.getSchema() + "." + seqName;
139 }
140
141 return seqName;
142 }
143
144
145
148 protected String createSequenceString(DbEntity ent) {
149 StringBuffer buf = new StringBuffer ();
150 buf.append("CREATE SEQUENCE ")
151 .append(this.sequenceName(ent))
152 .append(" START WITH 200")
153 .append(" INCREMENT BY ").append(getPkCacheSize())
154 .append(" NO MAXVALUE ")
155 .append(" NO CYCLE ")
156 .append(" CACHE ").append(getPkCacheSize());
157 return buf.toString();
158 }
159
160
163 protected String dropSequenceString(DbEntity ent) {
164 return "DROP SEQUENCE " + this.sequenceName(ent) + " RESTRICT ";
165 }
166
167
174 protected int pkFromDatabase(DataNode node, DbEntity ent) throws Exception {
175
176 String seq_name = sequenceName (ent);
177 Connection con = node.getDataSource().getConnection();
178 try {
179 Statement st = con.createStatement();
180 try {
181 String pkQueryString = "SELECT NEXTVAL FOR "
182 + seq_name
183 + " FROM SYSIBM.SYSDUMMY1";
184 QueryLogger.logQuery(QueryLogger.DEFAULT_LOG_LEVEL, pkQueryString, Collections.EMPTY_LIST);
185 ResultSet rs = st.executeQuery(pkQueryString);
186 try {
187 if (!rs.next()) {
188 throw new CayenneRuntimeException(
189 "Error in pkFromDatabase() for table "
190 + ent.getName()
191 + " / sequence "
192 + seq_name);
193 }
194 return rs.getInt(1);
195 } finally {
196 rs.close();
197 }
198 } finally {
199 st.close();
200 }
201 } finally {
202 con.close();
203 }
204 }
205
206
207
210 protected List getExistingSequences(DataNode node) throws SQLException {
211 Connection con = node.getDataSource().getConnection();
212 try {
213 Statement sel = con.createStatement();
214 try {
215 StringBuffer q = new StringBuffer ();
216 q.append("SELECT SEQNAME FROM SYSCAT.SEQUENCES WHERE SEQNAME")
217 .append(" LIKE '")
218 .append(SEQUENCE_PREFIX)
219 .append("%'");
220
221 ResultSet rs = sel.executeQuery(q.toString());
222 try {
223 List sequenceList = new ArrayList (32);
224 while (rs.next()) {
225 sequenceList.add(rs.getString(1));
226 }
227 return sequenceList;
228 } finally {
229 rs.close();
230 }
231 } finally {
232 sel.close();
233 }
234 } finally {
235 con.close();
236 }
237 }
238 }
239 |
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