/*
* This file is part of the WfMOpen project.
* Copyright (C) 2001-2004 Danet GmbH (www.danet.de), GS-AN.
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* $Id: UnivQueryTag.java 1607 2006-09-29 12:32:13Z drmlipp $
*
* $Log$
* Revision 1.1 2004/12/31 13:08:49 mlipp
* Added possibility to use UniversalPrepStmt in Jelly scripts.
*
*/
package de.danet.an.util.jellytags;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import javax.servlet.jsp.jstl.sql.Result;
import org.apache.commons.jelly.JellyTagException;
import org.apache.commons.jelly.XMLOutput;
import org.apache.commons.jelly.tags.Resources;
import org.apache.commons.jelly.tags.sql.QueryTag;
import org.apache.commons.jelly.tags.sql.ResultImpl;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import de.danet.an.util.UniversalPrepStmt;
/**
* This class provides a query tag that uses the {@link
* UniversalPrepStmt <code>universalPrepStmt} instead of the standard
* prepared statement.
*
* @author <a href="mailto:mnl@mnl.de">Michael N. Lipp</a>
* @version $Revision: 1607 $
*/
public class UnivQueryTag extends QueryTag {
/** The Log to which logging calls will be made. */
private static final Log logger = LogFactory.getLog(UnivQueryTag.class);
/*
* Instance variables that are not for attributes
*/
private Connection conn;
/**
* Creates an instance of <code>UnivQueryTag</code>
* with all attributes initialized to default values.
*/
public UnivQueryTag () {
}
/**
* Execute the SQL statement, set either through the <code>sql</code>
* attribute or as the body, and save the result as a variable
* named by the <code>var</code> attribute in the scope specified
* by the <code>scope</code> attribute, as an object that implements
* the Result interface.<p>
*
* The connection used to execute the statement comes either
* from the <code>DataSource</code> specified by the
* <code>dataSource</code> attribute, provided by a parent action
* element, or is retrieved from a JSP scope attribute
* named <code>javax.servlet.jstl.sql.dataSource</code>.<p>
*
* @param output the destination for the output
* @throws JellyTagException if an error occurs
*/
public void doTag(XMLOutput output) throws JellyTagException {
if (!maxRowsSpecified) {
Object obj = context.getVariable
("org.apache.commons.jelly.sql.maxRows");
if (obj != null) {
if (obj instanceof Integer) {
maxRows = ((Integer) obj).intValue();
} else if (obj instanceof String) {
try {
maxRows = Integer.parseInt((String) obj);
} catch (NumberFormatException nfe) {
throw new JellyTagException
(Resources.getMessage("SQL_MAXROWS_PARSE_ERROR",
(String) obj), nfe);
}
} else {
throw new JellyTagException
(Resources.getMessage("SQL_MAXROWS_INVALID"));
}
}
}
Result result = null;
String sqlStatement = null;
logger.debug( "About to lookup connection" );
ResultSet rs = null;
Statement statement = null;
try {
conn = getConnection();
/*
* Use the SQL statement specified by the sql attribute, if any,
* otherwise use the body as the statement.
*/
if (sql != null) {
sqlStatement = sql;
} else {
sqlStatement = getBodyText();
}
if (sqlStatement == null || sqlStatement.trim().length() == 0) {
throw new JellyTagException
(Resources.getMessage("SQL_NO_STATEMENT"));
}
// We shouldn't have a negative startRow or illegal maxrows
if ((startRow < 0) || (maxRows < -1)) {
throw new JellyTagException
(Resources.getMessage("PARAM_BAD_VALUE"));
}
/*
* Note! We must not use the setMaxRows() method on the
* the statement to limit the number of rows, since the
* Result factory must be able to figure out the correct
* value for isLimitedByMaxRows(); there's no way to check
* if it was from the ResultSet.
*/
if (logger.isDebugEnabled()) {
logger.debug( "About to execute query: " + sqlStatement );
}
if (hasParameters()) {
PreparedStatement ps
= new UniversalPrepStmt (conn, sqlStatement);
statement = ps;
setParameters(ps);
rs = ps.executeQuery();
} else {
statement = conn.createStatement();
rs = statement.executeQuery(sqlStatement);
}
result = new ResultImpl(rs, startRow, maxRows);
context.setVariable(var, result);
// always close the result set first since it may be closed by
// JDBC 3 when closing statements
// lets nullify before we close in case we get exceptions
// while closing, we don't want to try to close again
ResultSet tempRs = rs;
rs = null;
tempRs.close();
Statement tempStatement = statement;
statement = null;
tempStatement.close();
} catch (SQLException e) {
throw new JellyTagException
(sqlStatement + ": " + e.getMessage(), e);
} finally {
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {
logger.error
("Caught exception while closing result set: " + e, e);
}
}
if (statement != null) {
try {
statement.close();
} catch (SQLException e) {
logger.error
("Caught exception while closing statement: " + e, e);
}
}
if (conn != null && !isPartOfTransaction) {
try {
conn.close();
} catch (SQLException e) {
logger.error
("Caught exception while closing connection: " + e, e);
}
conn = null;
}
clearParameters();
}
}
}