org.apache.taglibs.standard.tag.el.sql.QueryTag Maven / Gradle / Ivy
/*
* Copyright (c) 1997, 2020 Oracle and/or its affiliates. All rights reserved.
* Copyright 2004 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.taglibs.standard.tag.el.sql;
import jakarta.servlet.jsp.JspException;
import org.apache.taglibs.standard.lang.support.ExpressionEvaluatorManager;
import org.apache.taglibs.standard.tag.common.sql.QueryTagSupport;
/**
* Subclass for the JSTL library with EL support.
*
* @author Hans Bergsten
* @author Justyna Horwat
*/
public class QueryTag extends QueryTagSupport {
private String dataSourceEL;
private String sqlEL;
private String startRowEL;
private String maxRowsEL;
//*********************************************************************
// Constructor
/**
* Constructs a new QueryTag. As with TagSupport, subclasses
* should not provide other constructors and are expected to call
* the superclass constructor
*/
public QueryTag() {
super();
}
//*********************************************************************
// Accessor methods
public void setDataSource(String dataSourceEL) {
this.dataSourceEL = dataSourceEL;
this.dataSourceSpecified = true;
}
/**
* The index of the first row returned can be
* specified using startRow.
*/
public void setStartRow(String startRowEL) {
this.startRowEL = startRowEL;
}
/**
* Query result can be limited by specifying
* the maximum number of rows returned.
*/
public void setMaxRows(String maxRowsEL) {
this.maxRowsEL = maxRowsEL;
this.maxRowsSpecified = true;
}
/**
* Setter method for the SQL statement to use for the
* query. The statement may contain parameter markers
* (question marks, ?). If so, the parameter values must
* be set using nested value elements.
*/
public void setSql(String sqlEL) {
this.sqlEL = sqlEL;
}
public int doStartTag() throws JspException {
evaluateExpressions();
return super.doStartTag();
}
//*********************************************************************
// Private utility methods
// Evaluates expressions as necessary
private void evaluateExpressions() throws JspException {
Integer tempInt = null;
if (dataSourceEL != null) {
rawDataSource = (Object) ExpressionEvaluatorManager.evaluate(
"dataSource", dataSourceEL, Object.class, this, pageContext);
}
if (sqlEL != null) {
sql = (String) ExpressionEvaluatorManager.evaluate("sql", sqlEL,
String.class, this, pageContext);
}
if (startRowEL != null) {
tempInt = (Integer) ExpressionEvaluatorManager.evaluate(
"startRow", startRowEL, Integer.class, this, pageContext);
if (tempInt != null)
startRow = tempInt.intValue();
}
if (maxRowsEL != null) {
tempInt = (Integer) ExpressionEvaluatorManager.evaluate(
"maxRows", maxRowsEL, Integer.class, this, pageContext);
if (tempInt != null)
maxRows = tempInt.intValue();
}
}
}