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47
48 import java.util.Vector  ;
49 import java.sql.*;
50 import javax.swing.table.AbstractTableModel ;
51 import javax.swing.event.TableModelEvent ;
52
53 public class JDBCAdapter extends AbstractTableModel {
54 Connection connection;
55 Statement statement;
56 ResultSet resultSet;
57 String [] columnNames = {};
58 Vector rows = new Vector ();
59 ResultSetMetaData metaData;
60
61 public JDBCAdapter(String url, String driverName,
62 String user, String passwd) {
63 try {
64 Class.forName(driverName);
65 System.out.println("Opening db connection");
66
67 connection = DriverManager.getConnection(url, user, passwd);
68 statement = connection.createStatement();
69 }
70 catch (ClassNotFoundException ex) {
71 System.err.println("Cannot find the database driver classes.");
72 System.err.println(ex);
73 }
74 catch (SQLException ex) {
75 System.err.println("Cannot connect to this database.");
76 System.err.println(ex);
77 }
78 }
79
80 public void executeQuery(String query) {
81 if (connection == null || statement == null) {
82 System.err.println("There is no database to execute the query.");
83 return;
84 }
85 try {
86 resultSet = statement.executeQuery(query);
87 metaData = resultSet.getMetaData();
88
89 int numberOfColumns = metaData.getColumnCount();
90 columnNames = new String [numberOfColumns];
91 for(int column = 0; column < numberOfColumns; column++) {
94 columnNames[column] = metaData.getColumnLabel(column+1);
95 }
96
97 rows = new Vector ();
99 while (resultSet.next()) {
100 Vector newRow = new Vector ();
101 for (int i = 1; i <= getColumnCount(); i++) {
102 newRow.addElement(resultSet.getObject(i));
103 }
104 rows.addElement(newRow);
105 }
106 fireTableChanged(null); }
109 catch (SQLException ex) {
110 System.err.println(ex);
111 }
112 }
113
114 public void close() throws SQLException {
115 System.out.println("Closing db connection");
116 resultSet.close();
117 statement.close();
118 connection.close();
119 }
120
121 protected void finalize() throws Throwable {
122 close();
123 super.finalize();
124 }
125
126
132
134 public String getColumnName(int column) {
135 if (columnNames[column] != null) {
136 return columnNames[column];
137 } else {
138 return "";
139 }
140 }
141
142 public Class getColumnClass(int column) {
143 int type;
144 try {
145 type = metaData.getColumnType(column+1);
146 }
147 catch (SQLException e) {
148 return super.getColumnClass(column);
149 }
150
151 switch(type) {
152 case Types.CHAR:
153 case Types.VARCHAR:
154 case Types.LONGVARCHAR:
155 return String .class;
156
157 case Types.BIT:
158 return Boolean .class;
159
160 case Types.TINYINT:
161 case Types.SMALLINT:
162 case Types.INTEGER:
163 return Integer .class;
164
165 case Types.BIGINT:
166 return Long .class;
167
168 case Types.FLOAT:
169 case Types.DOUBLE:
170 return Double .class;
171
172 case Types.DATE:
173 return java.sql.Date .class;
174
175 default:
176 return Object .class;
177 }
178 }
179
180 public boolean isCellEditable(int row, int column) {
181 try {
182 return metaData.isWritable(column+1);
183 }
184 catch (SQLException e) {
185 return false;
186 }
187 }
188
189 public int getColumnCount() {
190 return columnNames.length;
191 }
192
193
195 public int getRowCount() {
196 return rows.size();
197 }
198
199 public Object getValueAt(int aRow, int aColumn) {
200 Vector row = (Vector )rows.elementAt(aRow);
201 return row.elementAt(aColumn);
202 }
203
204 public String dbRepresentation(int column, Object value) {
205 int type;
206
207 if (value == null) {
208 return "null";
209 }
210
211 try {
212 type = metaData.getColumnType(column+1);
213 }
214 catch (SQLException e) {
215 return value.toString();
216 }
217
218 switch(type) {
219 case Types.INTEGER:
220 case Types.DOUBLE:
221 case Types.FLOAT:
222 return value.toString();
223 case Types.BIT:
224 return ((Boolean )value).booleanValue() ? "1" : "0";
225 case Types.DATE:
226 return value.toString(); default:
228 return "\""+value.toString()+"\"";
229 }
230
231 }
232
233 public void setValueAt(Object value, int row, int column) {
234 try {
235 String tableName = metaData.getTableName(column+1);
236 if (tableName == null) {
238 System.out.println("Table name returned null.");
239 }
240 String columnName = getColumnName(column);
241 String query =
242 "update "+tableName+
243 " set "+columnName+" = "+dbRepresentation(column, value)+
244 " where ";
245 for(int col = 0; col<getColumnCount(); col++) {
249 String colName = getColumnName(col);
250 if (colName.equals("")) {
251 continue;
252 }
253 if (col != 0) {
254 query = query + " and ";
255 }
256 query = query + colName +" = "+
257 dbRepresentation(col, getValueAt(row, col));
258 }
259 System.out.println(query);
260 System.out.println("Not sending update to database");
261 }
263 catch (SQLException e) {
264 System.err.println("Update failed");
266 }
267 Vector dataRow = (Vector )rows.elementAt(row);
268 dataRow.setElementAt(value, column);
269
270 }
271 }
272 |
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