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1 package net.sf.saxon.sql;
2
3 import net.sf.saxon.Controller;
4 import net.sf.saxon.event.Receiver;
5 import net.sf.saxon.event.ReceiverOptions;
6 import net.sf.saxon.expr.Expression;
7 import net.sf.saxon.expr.SimpleExpression;
8 import net.sf.saxon.expr.XPathContext;
9 import net.sf.saxon.instruct.Executable;
10 import net.sf.saxon.om.Item;
11 import net.sf.saxon.om.NamePool;
12 import net.sf.saxon.style.ExtensionInstruction;
13 import net.sf.saxon.style.StandardNames;
14 import net.sf.saxon.trans.DynamicError;
15 import net.sf.saxon.trans.XPathException;
16 import net.sf.saxon.value.ObjectValue;
17 import net.sf.saxon.value.StringValue;
18
19 import java.sql.Connection  ;
20 import java.sql.PreparedStatement ;
21 import java.sql.ResultSet ;
22 import java.sql.SQLException ;
23
24
43
44 public class SQLQuery extends ExtensionInstruction {
45
46 Expression connection;
47
50 Expression column;
51
54 Expression table;
55
58 Expression where;
59
60 String rowTag;
61
64 String colTag;
65
68
69 boolean disable = false;
71 public void prepareAttributes() throws XPathException {
72 String dbCol = attributeList.getValue("", "column");
74 if (dbCol == null) {
75 reportAbsence("column");
76 }
77 column = makeAttributeValueTemplate(dbCol);
78
79 String dbTab = attributeList.getValue("", "table");
80 if (dbTab == null) {
81 reportAbsence("table");
82 }
83 table = makeAttributeValueTemplate(dbTab);
84
85 String dbWhere = attributeList.getValue("", "where");
86 if (dbWhere == null) {
87 where = StringValue.EMPTY_STRING;
88 } else {
89 where = makeAttributeValueTemplate(dbWhere);
90 }
91
92 String connectAtt = attributeList.getValue("", "connection");
93 if (connectAtt == null) {
94 reportAbsence("connection");
95 } else {
96 connection = makeExpression(connectAtt);
97 }
98
99
101 rowTag = attributeList.getValue("", "row-tag");
102 if (rowTag == null) {
103 rowTag = "row";
104 }
105 if (rowTag.indexOf(':') >= 0) {
106 compileError("rowTag must not contain a colon");
107 }
108
109 colTag = attributeList.getValue("", "column-tag");
110 if (colTag == null) {
111 colTag = "col";
112 }
113 if (colTag.indexOf(':') >= 0) {
114 compileError("colTag must not contain a colon");
115 }
116 String disableAtt = attributeList.getValue("", "disable-output-escaping");
118 if (disableAtt != null) {
119 if (disableAtt.equals("yes")) {
120 disable = true;
121 } else if (disableAtt.equals("no")) {
122 disable = false;
123 } else {
124 compileError("disable-output-escaping attribute must be either yes or no");
125 }
126 }
127
128 }
129
130 public void validate() throws XPathException {
131 super.validate();
132 column = typeCheck("column", column);
133 table = typeCheck("table", table);
134 where = typeCheck("where", where);
135 connection = typeCheck("connection", connection);
136 }
137
138 public Expression compile(Executable exec) throws XPathException {
139 QueryInstruction inst = new QueryInstruction(connection,
140 column, table, where,
141 rowTag, colTag, disable);
142 return inst;
143 }
144
145 private static class QueryInstruction extends SimpleExpression {
146
147 public static final int CONNECTION = 0;
148 public static final int COLUMN = 1;
149 public static final int TABLE = 2;
150 public static final int WHERE = 3;
151 String rowTag;
152 String colTag;
153 int options;
154
155 public QueryInstruction(Expression connection,
156 Expression column,
157 Expression table,
158 Expression where,
159 String rowTag,
160 String colTag,
161 boolean disable) {
162 Expression[] sub = {connection, column, table, where};
163 setArguments(sub);
164 this.rowTag = rowTag;
165 this.colTag = colTag;
166 this.options = (disable ? ReceiverOptions.DISABLE_ESCAPING : 0);
167 }
168
169
173
174 public int getImplementationMethod() {
175 return Expression.PROCESS_METHOD;
176 }
177
178 public String getExpressionType() {
179 return "sql:query";
180 }
181
182 public void process(XPathContext context) throws XPathException {
183
185 Controller controller = context.getController();
186 Item conn = arguments[CONNECTION].evaluateItem(context);
187 if (!(conn instanceof ObjectValue && ((ObjectValue)conn).getObject() instanceof Connection )) {
188 DynamicError de = new DynamicError("Value of connection expression is not a JDBC Connection");
189 de.setXPathContext(context);
190 throw de;
191 }
192 Connection connection = (Connection )((ObjectValue)conn).getObject();
193
194 String dbCol = arguments[COLUMN].evaluateAsString(context);
195 String dbTab = arguments[TABLE].evaluateAsString(context);
196 String dbWhere = arguments[WHERE].evaluateAsString(context);
197
198
199 NamePool pool = controller.getNamePool();
200 int rowCode = pool.allocate("", "", rowTag);
201 int colCode = pool.allocate("", "", colTag);
202
203 PreparedStatement ps = null;
204 ResultSet rs = null;
205 DynamicError de = null;
206
207 try {
208 StringBuffer statement = new StringBuffer ();
209 statement.append("SELECT " + dbCol + " FROM " + dbTab);
210 if (dbWhere != "") {
211 statement.append(" WHERE " + dbWhere);
212 }
213
215 ps = connection.prepareStatement(statement.toString());
217 controller.setUserData(this, "sql:statement", ps);
218
219 rs = ps.executeQuery();
221
222 Receiver out = context.getReceiver();
224 String result = "";
225 int icol = rs.getMetaData().getColumnCount();
226 while (rs.next()) { out.startElement(rowCode, StandardNames.XDT_UNTYPED, locationId, 0);
229 for (int col = 1; col <= icol; col++) { result = rs.getString(col);
233 out.startElement(colCode, StandardNames.XDT_UNTYPED, locationId, 0);
234 if (result != null) {
235 out.characters(result, locationId, options);
236 }
237 out.endElement();
238 }
239 out.endElement();
241 }
242
244 if (!connection.getAutoCommit()) {
245 connection.commit();
246 }
247
248 } catch (SQLException ex) {
249 de = new DynamicError("(SQL) " + ex.getMessage());
250 de.setXPathContext(context);
251 throw de;
252 } finally {
253 boolean wasDEThrown = (de != null);
254 if (rs != null) {
255 try {
256 rs.close();
257 } catch (SQLException ex) {
258 de = new DynamicError("(SQL) " + ex.getMessage());
259 de.setXPathContext(context);
260 }
261 }
262 if (ps != null) {
263 try {
264 ps.close();
265 } catch (SQLException ex) {
266 de = new DynamicError("(SQL) " + ex.getMessage());
267 de.setXPathContext(context);
268 }
269 }
270 if (!wasDEThrown && de != null) {
271 throw de; }
273 }
274 }
275 }
276 }
277
278
279
280 |
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