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17
18 package org.objectweb.jac.aspects.persistence;
19
20 import java.sql.Connection  ;
21 import java.sql.DriverManager ;
22 import java.sql.ResultSet ;
23 import java.sql.SQLException ;
24 import java.util.HashSet ;
25 import java.util.Hashtable ;
26 import java.util.Iterator ;
27 import java.util.Map.Entry;
28 import java.util.Map ;
29 import org.apache.log4j.Level;
30 import org.apache.log4j.Logger;
31 import org.objectweb.jac.util.Log;
32 import org.objectweb.jac.util.Strings;
33
34
35
38
39 public class PostgresStorage extends SQLStorage {
40 static Logger logger = Logger.getLogger("persistence.storage");
41
42
43 static final int version = 1;
44
45
57 public PostgresStorage(PersistenceAC ac,
58 String database, String user, String password)
59 throws SQLException , Exception
60 {
61 super(ac);
62 try {
63 Class.forName("org.postgresql.Driver");
64 } catch (ClassNotFoundException e) {
65 logger.error("failed to load postgresql JDBC driver",e);
66 return;
67 }
68 try {
69 Connection db;
70 db = DriverManager.getConnection("jdbc:postgresql:"+database,user,password);
71 setConnection(db);
72 } catch (SQLException e) {
73 logger.error("failed to connect to the database with "+
74 "jdbc:postgresql:"+database+","+user+","+password,e);
75 return;
76 }
77
78 try {
79 doUpdates();
80 } catch (Exception e) {
81 logger.error("doUpdates failed on "+database,e);
82 }
83 }
84
85 protected String [] getClassNames() throws Exception {
86 ResultSet rs = executeQuery("SELECT DISTINCT classid FROM classes");
87 HashSet names = new HashSet ();
88 while (rs.next()) {
89 names.add(rs.getString("classid"));
90 }
91 return (String [])names.toArray(new String [0]);
92 }
93
94 protected void doUpdates() throws Exception , SQLException {
95 if (!hasTable("storage")) {
96 execute(
97 "create table \"storage\" ("+
98 "\"key\" character varying PRIMARY KEY, "+
99 "\"value\" character varying )");
100 }
101 int currentVersion = getInt("select value from storage where key='version'",0);
102
103 if (currentVersion<=0) {
104 logger.info("Upgrading from version 0");
105 String [] classes = getClassNames();
107 HashSet seqs = new HashSet ();
108 for (int i=0; i<classes.length; i++) {
109 String seq = Strings.getShortClassName(classes[i]).toLowerCase()+"_seq";
110 if (seqs.contains(seq))
111 throw new RuntimeException (
112 "Cannot upgrade storage: two classes have the same seq name '"+seq+"'");
113 seqs.add(seq);
114 }
115
116 for (int i=0; i<classes.length; i++) {
117 String seq = Strings.getShortClassName(classes[i]).toLowerCase()+"_seq";
118 if (hasSequence(seq)) {
119 logger.debug("Renaming sequence "+seq+" to "+classes[i]);
120 executeUpdate("ALTER TABLE "+seq+" RENAME to \""+classes[i]+"\"");
121 } else {
122 logger.debug("No such sequence "+seq);
123 }
124 }
125
126 }
127
128 if (currentVersion==0)
129 executeUpdate("insert into storage values ('version',"+version+") ");
130 else
131 executeUpdate("update storage set value="+version+" where key='version'");
132 }
133
134 public long getNextVal(String sequence) throws Exception {
135 ensureSequenceExists(sequence);
136 return getLong("select nextval('\""+sequence+"\"')");
137 }
138
139 public long getCurrVal(String sequence) throws Exception {
140 ensureSequenceExists(sequence);
141 return getLong("select last_value from \""+sequence+"\"");
142 }
143
144 protected boolean ensureSequenceExists(String sequence) throws Exception {
145 boolean created = false;
146 if (!createdSequences.contains(sequence)) {
147 if (!hasSequence(sequence)) {
148 execute("create sequence \""+sequence+"\"");
149 created = true;
150 }
151 createdSequences.add(sequence);
152 }
153 return created;
154 }
155
156 HashSet createdSequences = new HashSet ();
157 public String newName(String className) throws Exception {
158 String prefix = Strings.getShortClassName(className).toLowerCase();
159 String seq = getClassSeqName(className);
160 return prefix+"#"+(getNextVal(seq)-1);
161 }
162
163 public Map getNameCounters() throws Exception {
164 Hashtable counters = new Hashtable ();
165 String [] classes = getClassNames();
166 for (int i=0; i<classes.length; i++) {
167 String seq = getClassSeqName(classes[i]);
168 counters.put(classes[i],new Long (getCurrVal(seq)));
169 }
170
171 return counters;
172 }
173
174 protected String getClassSeqName(String className) {
175 return className;
176 }
177
178 protected boolean hasTable(String name) throws SQLException {
179 ResultSet rs =
180 executeQuery("select * from pg_tables where tablename='"+name+"'");
181 return rs.next();
182 }
183
184 protected boolean hasSequence(String name) throws Exception {
185 ResultSet rs =
186 executeQuery("select * from pg_class where relname='"+name+"' and relkind='S'");
187 return rs.next();
188 }
189
190 public void updateNameCounters(Map counters) throws Exception {
191 Iterator i = counters.entrySet().iterator();
192 while (i.hasNext()) {
193 Entry entry = (Entry)i.next();
194 String sequence = getClassSeqName((String )entry.getKey());
195 ensureSequenceExists(sequence);
196 if (getCurrVal(sequence)<((Long )entry.getValue()).longValue())
197 execute("select setval('\""+sequence+"\"',"+entry.getValue()+",true)");
198 }
199 }
200
201 }
202 |
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