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1
10 package com.triactive.jdo.store;
11
12 import com.triactive.jdo.PersistenceManager;
13 import com.triactive.jdo.StateManager;
14 import java.io.IOException  ;
15 import java.io.InputStreamReader ;
16 import java.sql.Connection ;
17 import java.sql.PreparedStatement ;
18 import java.sql.ResultSet ;
19 import java.sql.SQLException ;
20 import java.sql.Types ;
21 import javax.jdo.JDODataStoreException;
22 import oracle.sql.CLOB;
23 import org.apache.log4j.Category;
24
25
26 public class OracleClobMapping extends StringMapping implements PostInsertProcessing, PostUpdateProcessing
27 {
28 private static final Category LOG = Category.getInstance(OracleClobMapping.class);
29
30 private final ClassBaseTable table;
31 private final int absoluteFieldNumber;
32 private ColumnMapping idMapping = null;
33 private String fetchStmt = null;
34
35
36 public OracleClobMapping(ClassBaseTable table, int relativeFieldNumber)
37 {
38 super(table.newColumn(relativeFieldNumber));
39
40 if (col.getLengthType() != Column.UNLIMITED_LENGTH)
41 throw new ColumnDefinitionException("Invalid length specified for CLOB column " + col + ", must be 'unlimited'");
42
43 this.table = table;
44 this.absoluteFieldNumber = relativeFieldNumber + table.getClassMetaData().getInheritedFieldCount();
45 }
46
47
48 private synchronized void initialize()
49 {
50 if (idMapping == null)
51 {
52 idMapping = table.getIDMapping();
53
54 FetchStatement stmt = new FetchStatement(table);
55 stmt.select(getColumn());
56 stmt.andCondition(stmt.referenceColumn(idMapping.getColumn()) + " = ?");
57
58 fetchStmt = stmt.toString() + " FOR UPDATE";
59 }
60 }
61
62
63 protected TypeInfo getTypeInfo()
64 {
65 return dba.getTypeInfo(Types.CLOB);
66 }
67
68
69 public String getSQLInsertionValue()
70 {
71 return "EMPTY_CLOB()";
72 }
73
74
75 public String getSQLUpdateValue()
76 {
77 return "EMPTY_CLOB()";
78 }
79
80
81 public void setString(PersistenceManager pm, PreparedStatement ps, int param, String value)
82 {
83 }
85
86
87 public String getString(PersistenceManager pm, ResultSet rs, int param)
88 {
89 String value = null;
90
91 try
92 {
93 char[] cbuf = null;
94 CLOB clob = (CLOB)rs.getClob(param);
95
96 if (clob != null)
97 {
98
101 StringBuffer sbuf = new StringBuffer ();
102 InputStreamReader reader = new InputStreamReader (clob.asciiStreamValue());
103 long size = clob.length();
104
105 try
106 {
107 final int BUFF_SIZE = 4096;
108 cbuf = new char[BUFF_SIZE];
109 int charsRead = reader.read(cbuf);
110
111 while (-1 != charsRead)
112 {
113 sbuf.append(cbuf, 0, charsRead );
114
115 java.util.Arrays.fill(cbuf, (char)0);
116 charsRead = reader.read(cbuf);
117 }
118
119 }
120 catch (IOException e)
121 {
122 throw new JDODataStoreException("Error reading Oracle CLOB object: param = " + param, e);
123 }
124
125 value = sbuf.toString();
126
127 if (value.length() == 0)
128 value = null;
129 else if (value.equals(OracleStringMapping.EMPTY_STRING_SURROGATE))
130 value = "";
131 }
132 }
133 catch (SQLException e)
134 {
135 throw dba.newDataStoreException("Can't get String result: param = " + param, e);
136 }
137
138 return value;
139 }
140
141
142 public void setObject(PersistenceManager pm, PreparedStatement ps, int param, Object value)
143 {
144 setString(pm, ps, param, (String )value);
145 }
146
147
148 public Object getObject(PersistenceManager pm, ResultSet rs, int param)
149 {
150 return getString(pm, rs, param);
151 }
152
153
154 public void postInsert(StateManager sm, Connection conn, Object value)
155 {
156 postUpdate(sm, conn, value);
157 }
158
159
160
164 public void postUpdate(StateManager sm, Connection conn, Object value)
165 {
166 initialize();
167
168 String strval = (String )value;
169
170 if (strval == null)
171 strval = "";
172 else if (strval.length() == 0)
173 strval = OracleStringMapping.EMPTY_STRING_SURROGATE;
174
175 PersistenceManager pm = sm.getPersistenceManager();
176
177 try
178 {
179 PreparedStatement ps = conn.prepareStatement(fetchStmt);
180
181 try
182 {
183 Object id = sm.getObjectId();
184 idMapping.setObject(pm, ps, 1, id);
185
186 long startTime = System.currentTimeMillis();
187
188 ResultSet rs = ps.executeQuery();
189
190 try
191 {
192 if (LOG.isDebugEnabled())
193 LOG.debug("Time = " + (System.currentTimeMillis() - startTime) + " ms: " + fetchStmt);
194
195 if (!rs.next())
196 throw new ObjectNotFoundException("No such database row", sm.getObject());
197
198 CLOB clob = (CLOB)rs.getClob(1);
199
200 clob.putString(1, strval);
201 }
202 finally
203 {
204 rs.close();
205 }
206 }
207 finally
208 {
209 ps.close();
210 }
211 }
212 catch (SQLException e)
213 {
214 throw dba.newDataStoreException("CLOB update failed: " + fetchStmt, e);
215 }
216 }
217 }
218 |
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