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1
16
17 package org.apache.taglibs.standard.tag.common.sql;
18
19 import java.sql.Connection  ;
20 import java.sql.PreparedStatement ;
21 import java.sql.ResultSet ;
22 import java.sql.SQLException ;
23 import java.util.ArrayList ;
24 import java.util.List ;
25
26 import javax.servlet.jsp.JspException ;
27 import javax.servlet.jsp.JspTagException ;
28 import javax.servlet.jsp.PageContext ;
29 import javax.servlet.jsp.jstl.core.Config;
30 import javax.servlet.jsp.jstl.sql.Result;
31 import javax.servlet.jsp.jstl.sql.SQLExecutionTag;
32 import javax.servlet.jsp.tagext.BodyTagSupport ;
33 import javax.servlet.jsp.tagext.TryCatchFinally ;
34 import javax.sql.DataSource ;
35
36 import org.apache.taglibs.standard.resources.Resources;
37 import org.apache.taglibs.standard.tag.common.core.Util;
38
39
40
46
47 public abstract class QueryTagSupport extends BodyTagSupport
48 implements TryCatchFinally , SQLExecutionTag {
49
50 private String var;
51 private int scope;
52
53
58 protected Object rawDataSource;
59 protected boolean dataSourceSpecified;
60 protected String sql;
61 protected int maxRows;
62 protected boolean maxRowsSpecified;
63 protected int startRow;
64
65
68 private Connection conn;
69 private List parameters;
70 private boolean isPartOfTransaction;
71
72
73
76 public QueryTagSupport() {
77 super();
78 init();
79 }
80
81 private void init() {
82 startRow = 0;
83 maxRows = -1;
84 maxRowsSpecified = dataSourceSpecified = false;
85 isPartOfTransaction = false;
86 conn = null;
87 rawDataSource = null;
88 parameters = null;
89 sql = null;
90 var = null;
91 scope = PageContext.PAGE_SCOPE;
92 }
93
94
95
98
102 public void setVar(String var) {
103 this.var = var;
104 }
105
106
110 public void setScope(String scopeName) {
111 scope = Util.getScope(scopeName);
112 }
113
114
117
121 public void addSQLParameter(Object o) {
122 if (parameters == null) {
123 parameters = new ArrayList ();
124 }
125 parameters.add(o);
126 }
127
128
131
135 public int doStartTag() throws JspException {
136
137 if (!maxRowsSpecified) {
138 Object obj = Config.find(pageContext, Config.SQL_MAX_ROWS);
139 if (obj != null) {
140 if (obj instanceof Integer ) {
141 maxRows = ((Integer ) obj).intValue();
142 } else if (obj instanceof String ) {
143 try {
144 maxRows = Integer.parseInt((String ) obj);
145 } catch (NumberFormatException nfe) {
146 throw new JspException (
147 Resources.getMessage("SQL_MAXROWS_PARSE_ERROR",
148 (String ) obj),
149 nfe);
150 }
151 } else {
152 throw new JspException (
153 Resources.getMessage("SQL_MAXROWS_INVALID"));
154 }
155 }
156 }
157
158 try {
159 conn = getConnection();
160 } catch (SQLException e) {
161 throw new JspException (sql + ": " + e.getMessage(), e);
162 }
163
164 return EVAL_BODY_BUFFERED;
165 }
166
167
180 public int doEndTag() throws JspException {
181
185 String sqlStatement = null;
186 if (sql != null) {
187 sqlStatement = sql;
188 }
189 else if (bodyContent != null) {
190 sqlStatement = bodyContent.getString();
191 }
192 if (sqlStatement == null || sqlStatement.trim().length() == 0) {
193 throw new JspTagException (
194 Resources.getMessage("SQL_NO_STATEMENT"));
195 }
196
199 if ((startRow < 0) || (maxRows < -1)) {
200 throw new JspException (
201 Resources.getMessage("PARAM_BAD_VALUE"));
202 }
203
204 Result result = null;
205
212 PreparedStatement ps = null;
213 try {
214 ps = conn.prepareStatement(sqlStatement);
215 setParameters(ps, parameters);
216 ResultSet rs = ps.executeQuery();
217 result = new ResultImpl(rs, startRow, maxRows);
218 }
219 catch (Throwable e) {
220 throw new JspException (sqlStatement + ": " + e.getMessage(), e);
221 } finally {
222 if (ps != null) {
223 try {
224 ps.close();
225 } catch (SQLException sqe) {
226 throw new JspException (sqe.getMessage(), sqe);
227 }
228 }
229 }
230 pageContext.setAttribute(var, result, scope);
231 return EVAL_PAGE;
232 }
233
234
237 public void doCatch(Throwable t) throws Throwable {
238 throw t;
239 }
240
241
245 public void doFinally() {
246 if (conn != null && !isPartOfTransaction) {
247 try {
248 conn.close();
249 } catch (SQLException e) {} }
251
252 conn = null;
253 parameters = null;
254 }
255
256
257
260 private Connection getConnection() throws JspException , SQLException {
261 Connection conn = null;
263 isPartOfTransaction = false;
264
265 TransactionTagSupport parent = (TransactionTagSupport)
266 findAncestorWithClass(this, TransactionTagSupport.class);
267 if (parent != null) {
268 if (dataSourceSpecified) {
269 throw new JspTagException (
270 Resources.getMessage("ERROR_NESTED_DATASOURCE"));
271 }
272 conn = parent.getSharedConnection();
273 isPartOfTransaction = true;
274 } else {
275 if ((rawDataSource == null) && dataSourceSpecified) {
276 throw new JspException (
277 Resources.getMessage("SQL_DATASOURCE_NULL"));
278 }
279 DataSource dataSource = DataSourceUtil.getDataSource(rawDataSource,
280 pageContext);
281 try {
282 conn = dataSource.getConnection();
283 } catch (Exception ex) {
284 throw new JspException (
285 Resources.getMessage("DATASOURCE_INVALID",
286 ex.toString()));
287 }
288 }
289
290 return conn;
291 }
292
293 private void setParameters(PreparedStatement ps, List parameters)
294 throws SQLException
295 {
296 if (parameters != null) {
297 for (int i = 0; i < parameters.size(); i++) {
298
303 ps.setObject(i + 1, parameters.get(i));
304 }
305 }
306 }
307 }
308 |
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