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1 package com.quadcap.sql;
2
3
40
41 import java.io.Externalizable  ;
42 import java.io.IOException ;
43 import java.io.ObjectInput ;
44 import java.io.ObjectOutput ;
45
46 import java.util.Enumeration ;
47 import java.util.Hashtable ;
48 import java.util.Vector ;
49
50 import java.sql.SQLException ;
51
52 import com.quadcap.sql.types.Type;
53 import com.quadcap.sql.types.TypeAny;
54 import com.quadcap.sql.types.Value;
55
56 import com.quadcap.util.Debug;
57
58
64 public class ItemsCursor extends CursorImpl {
65 Cursor cursor;
66 ItemsRow currentRow = null;
67 int[] map = null;
68 Vector items;
69
70 public ItemsCursor(Session session, Cursor cursor, Vector gitems)
71 throws SQLException
72 {
73 super(session, cursor.getName());
74 this.session = session;
75 this.cursor = cursor;
76 this.items = expandWildCard(session, cursor, gitems);
77 this.map = new int[items.size()];
78 for (int i = 0; i < items.size(); i++) {
79 SelectItem item = (SelectItem)items.elementAt(i);
80 Expression e = item.getExpression();
81 if (e instanceof NameExpression) {
82 String name = ((NameExpression)e).getName();
83 String asName = item.getAsName();
84 if (asName == null) asName = name;
85 Column col = cursor.getColumn(name);
86 if (col == null) {
87 Debug.println(0, cursor.toString());
89 throw new SQLException ("Bad column name: " + name,
91 "42000");
92 }
93 addColumn(new Column(asName, col));
94 map[i] = col.getColumn();
95 } else {
96 String asName = item.getAsName();
97 if (asName == null) {
98 asName = "Column" + (i+1);
99 }
100 addColumn(new Column(asName, e.getType(session, cursor)));
101 map[i] = -1;
102 }
103 }
104 }
105
106 final Vector expandWildCard(Session session, Cursor cursor, Vector items)
107 throws SQLException
108 {
109 Vector nitems = new Vector ();
110 for (int i = 0; i < items.size(); i++) {
111 SelectItem item = (SelectItem)items.elementAt(i);
112 Expression e = item.getExpression();
113 String name = "Column" + (i + 1);
114 if (e instanceof NameExpression) {
115 name = ((NameExpression)e).getName();
116 if (name.endsWith(".*")) {
117 String rname = name.substring(0, name.length() - 2);
118 String qname =
119 session.getConnection().resolveName(rname) + ".";
120 rname = rname + ".";
121 boolean found = false;
122 for (int j = 1; j <= cursor.getColumnCount(); j++) {
123 Column col = cursor.getColumn(j);
124 if (col.isJoinColumn()) continue;
125 String sname = col.getShortName();
126 String cname = col.getName();
127 if (sname.startsWith(rname) || sname.startsWith(qname)) {
128 found = true;
129 nitems.addElement(
130 new SelectItem(new NameExpression(sname)));
131 } else if (cname.startsWith(qname) || cname.startsWith(rname)) {
132 found = true;
133 nitems.addElement(
134 new SelectItem(new NameExpression(cname)));
135 }
136 }
137 if (!found) {
138 throw new SQLException ("Bad column name: " + name,
139 "42000");
140 }
141 } else {
142 nitems.addElement(item);
143 }
144 } else {
145 nitems.addElement(item);
146 }
147 }
148 return nitems;
149 }
150
151 public Row getEmptyAggregate() throws SQLException {
152 return new ItemsRow(session, items, null, null, map);
153 }
154
155 public void updateRow(Row row) throws SQLException {
156 for (int i = 1; i <= map.length; i++) {
157 Value v = row.item(i);
158 currentRow.set(i, v);
159 }
160 cursor.updateRow(currentRow.getBaseRow());
161 }
162
163 public void insertRow(Row row) throws SQLException {
164 if (currentRow == null) {
165 makeCurrentRow();
166 }
167 for (int i = 1; i <= map.length; i++) {
168 Value v = row.item(i);
169 currentRow.set(i, v);
170 }
171 cursor.insertRow(currentRow.getBaseRow());
172 }
173
174 public void deleteRow() throws SQLException {
175 cursor.deleteRow();
176 }
177
178 public boolean isWritable(int column) throws SQLException {
179 return cursor.isWritable(map[column-1]);
180 }
181
182 public void beforeFirst() throws SQLException {
183 cursor.beforeFirst();
184 }
185
186 public void afterLast() throws SQLException {
187 cursor.afterLast();
188 }
189
190 final void makeFirstRow() throws SQLException {
191 Row r = cursor.getRow();
192 currentRow = new ItemsRow(session, items, cursor, r, map);
193 for (int i = 0; i < map.length; i++) {
194 if (map[i] == -1) {
195 Column col = getColumn(i+1);
196 Value v = currentRow.item(i+1);
197 col.setType(v.getType());
198 }
199 }
200 }
201
202 final void makeCurrentRow() throws SQLException {
203 currentRow = new ItemsRow(session, items, cursor, null, map);
204 }
205
206 public boolean next() throws SQLException {
207 return cursor.next();
208 }
209
210 public Row getRow() throws SQLException {
211 if (currentRow == null) {
212 makeFirstRow();
213 } else {
214 currentRow.nextRow(cursor.getRow());
215 }
216 return currentRow;
217 }
218
219 public void setOuterCursor(Cursor c) {
220 super.setOuterCursor(c);
221 if (cursor != null) cursor.setOuterCursor(c);
222 }
223
224 public void close() throws SQLException {
225 cursor.close();
226 }
227
228 public long size() throws SQLException { return cursor.size(); }
229
230 public Cursor getBaseCursor() { return cursor; }
231
232 public String toString() {
234 return super.toString() + " : (cursor = " + cursor + ")";
235 }
236
238 }
239 |
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