|
1
33 package smallsql.database;
34
35 import java.sql.*;
36 import java.util.ArrayList  ;
37 import java.util.List ;
38
39
40
44 class MemoryResult extends DataSource {
45
46 ExpressionValue[] currentRow;
47 private final Columns columns = new Columns();
48 private int rowIdx = -1;
49 private List rowList = new ArrayList ();
51
54 MemoryResult(){}
55
56
57
60 MemoryResult(Object [][] data, int colCount) throws SQLException{
61 for(int c=0; c<colCount; c++){
62 Column column = new Column();
63 column.setDataType(SQLTokenizer.NULL);
64 columns.add( column );
65 }
66 for(int r=0; r<data.length; r++){
67 Object [] row = data[r];
68 ExpressionValue[] rowValues = new ExpressionValue[row.length];
69 addRow(rowValues);
70 for(int c=0; c<colCount; c++){
71 ExpressionValue expr = rowValues[c] = new ExpressionValue();
72 expr.set( row[c], -1);
73 Column column = columns.get(c);
74 if(expr.getDataType() != SQLTokenizer.NULL){
75 column.setDataType(expr.getDataType());
76 }
77 if(expr.getPrecision() > column.getPrecision()){
78 column.setPrecision(expr.getPrecision());
79 }
80 }
81 }
82 }
83
84 final void addRow(ExpressionValue[] row){
85 rowList.add(row);
86 }
87
88
89
93 final Column getColumn(int colIdx){
94 return columns.get(colIdx);
95 }
96
97
98
102 final void addColumn(Column column){
103 columns.add(column);
104 }
105
106
111
112
113 final boolean isScrollable(){
114 return true;
115 }
116
117
118 final void beforeFirst(){
119 rowIdx = -1;
120 currentRow = null;
121 }
122
123 final boolean isBeforeFirst(){
124 return rowIdx < 0;
125 }
126
127 final boolean isFirst(){
128 return rowIdx == 0 && currentRow != null;
129 }
130
131 final boolean first(){
132 rowIdx = 0;
133 return move();
134 }
135
136 final boolean previous(){
137 if(rowIdx-- < 0) rowIdx = -1;
138 return move();
139 }
140
141 final boolean next(){
142 rowIdx++;
143 return move();
144 }
145
146 final boolean last(){
147 rowIdx = rowList.size() - 1;
148 return move();
149 }
150
151
152 final boolean isLast(){
153 return rowIdx == rowList.size() - 1 && currentRow != null;
154 }
155
156 final boolean isAfterLast(){
157 return rowIdx >= rowList.size();
158 }
159
160 final void afterLast(){
161 rowIdx = rowList.size();
162 currentRow = null;
163 }
164
165
166 final boolean absolute(int row) throws SQLException{
167 if(row == 0) throw Utils.createSQLException("Row 0 is invalid for method absolute().");
168 rowIdx = (row > 0) ?
169 Math.min( row, rowList.size() ) :
170 Math.min( row +rowList.size(), -1 );
171 return move();
172 }
173
174
175 final boolean relative(int rows){
176 if(rows == 0) return (currentRow != null);
177 rowIdx = Math.min( Math.max( rowIdx + rows, -1), rowList.size());
178 return move();
179 }
180
181
182 final int getRow(){
183 return currentRow == null ? 0 : rowIdx+1;
184 }
185
186
187 final long getRowPosition(){
188 return rowIdx;
189 }
190
191
192 final void setRowPosition(long rowPosition) throws Exception {
193 rowIdx = (int)rowPosition;
194 move();
195 }
196
197
198 final boolean rowInserted(){
199 return false;
200 }
201
202
203 final boolean rowDeleted(){
204 return false;
205 }
206
207
208 void nullRow(){
209 throw new Error ();
210 }
211
212
213 void noRow(){
214 currentRow = null;
215 }
216
217
218 final private boolean move(){
219 if(rowIdx < rowList.size() && rowIdx >= 0){
220 currentRow = (ExpressionValue[])rowList.get(rowIdx);
221 return true;
222 }
223 currentRow = null;
224 return false;
225 }
226
227
232
233 boolean isNull( int colIdx ) throws Exception {
234 return get( colIdx ).isNull();
235 }
236
237
238 boolean getBoolean( int colIdx ) throws Exception {
239 return get( colIdx ).getBoolean();
240 }
241
242 int getInt( int colIdx ) throws Exception {
243 return get( colIdx ).getInt();
244 }
245
246 long getLong( int colIdx ) throws Exception {
247 return get( colIdx ).getLong();
248 }
249
250 float getFloat( int colIdx ) throws Exception {
251 return get( colIdx ).getFloat();
252 }
253
254 double getDouble( int colIdx ) throws Exception {
255 return get( colIdx ).getDouble();
256 }
257
258 long getMoney( int colIdx ) throws Exception {
259 return get( colIdx ).getMoney();
260 }
261
262 MutableNumeric getNumeric( int colIdx ) throws Exception {
263 return get( colIdx ).getNumeric();
264 }
265
266 Object getObject( int colIdx ) throws Exception {
267 return get( colIdx ).getObject();
268 }
269
270 String getString( int colIdx ) throws Exception {
271 return get( colIdx ).getString();
272 }
273
274
275 byte[] getBytes( int colIdx ) throws Exception {
276 return get( colIdx ).getBytes();
277 }
278
279
280 int getDataType( int colIdx ){
281 return columns.get( colIdx ).getDataType();
282 }
284
285
286 final TableView getTableView(){
287 return null;
288 }
289
290
291 final void deleteRow() throws Exception {
292 throw Utils.createSQLException("ResultSet is read only.");
293 }
294
295
296 final void updateRow(Expression[] updateValues) throws Exception {
297 throw Utils.createSQLException("ResultSet is read only.");
298 }
299
300
301 final void insertRow(Expression[] updateValues) throws Exception {
302 throw Utils.createSQLException("ResultSet is read only.");
303 }
304
305
306
307
308
311
312
317 private Expression get(int colIdx) throws Exception {
318 if(currentRow == null) throw Utils.createSQLException("No current row.");
319 return currentRow[ colIdx ];
320 }
321
322
323
326 int getRowCount(){
327 return rowList.size();
328 }
329
330
331 void execute() throws Exception {
332 rowList.clear();
333 }
334 }
335 |
Popular Tags |
Java API By Example, From Geeks To Geeks.