org.apache.taglibs.standard.tag.common.sql.UpdateTagSupport Maven / Gradle / Ivy
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/*
* 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.common.sql;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import jakarta.servlet.jsp.JspException;
import jakarta.servlet.jsp.JspTagException;
import jakarta.servlet.jsp.PageContext;
import jakarta.servlet.jsp.jstl.sql.SQLExecutionTag;
import jakarta.servlet.jsp.tagext.BodyTagSupport;
import jakarta.servlet.jsp.tagext.TryCatchFinally;
import javax.sql.DataSource;
import org.apache.taglibs.standard.resources.Resources;
import org.apache.taglibs.standard.tag.common.core.Util;
/**
* Tag handler for <Update> in JSTL.
*
* @author Hans Bergsten
* @author Justyna Horwat
*/
public abstract class UpdateTagSupport extends BodyTagSupport
implements TryCatchFinally, SQLExecutionTag {
private String var;
private int scope;
/*
* The following properties take expression values, so the
* setter methods are implemented by the expression type
* specific subclasses.
*/
protected Object rawDataSource;
protected boolean dataSourceSpecified;
protected String sql;
/*
* Instance variables that are not for attributes
*/
private Connection conn;
private List parameters;
private boolean isPartOfTransaction;
//*********************************************************************
// Constructor and initialization
public UpdateTagSupport() {
super();
init();
}
private void init() {
rawDataSource = null;
sql = null;
conn = null;
parameters = null;
isPartOfTransaction = dataSourceSpecified = false;
scope = PageContext.PAGE_SCOPE;
var = null;
}
//*********************************************************************
// Accessor methods
/**
* Setter method for the name of the variable to hold the
* result.
*/
public void setVar(String var) {
this.var = var;
}
/**
* Setter method for the scope of the variable to hold the
* result.
*/
public void setScope(String scopeName) {
scope = Util.getScope(scopeName);
}
//*********************************************************************
// Tag logic
/**
* Prepares for execution by setting the initial state, such as
* getting the Connection
*/
public int doStartTag() throws JspException {
try {
conn = getConnection();
} catch (SQLException e) {
throw new JspException(sql + ": " + e.getMessage(), e);
}
return EVAL_BODY_BUFFERED;
}
/**
*
Execute the SQL statement, set either through the sql
* attribute or as the body, and save the result as a variable
* named by the var attribute in the scope specified
* by the scope attribute, as an object that implements
* the Result interface.
*
*
The connection used to execute the statement comes either
* from the DataSource specified by the
* dataSource attribute, provided by a parent action
* element, or is retrieved from a JSP scope attribute
* named jakarta.servlet.jsp.jstl.sql.dataSource.
*/
public int doEndTag() throws JspException {
/*
* Use the SQL statement specified by the sql attribute, if any,
* otherwise use the body as the statement.
*/
String sqlStatement = null;
if (sql != null) {
sqlStatement = sql;
}
else if (bodyContent != null) {
sqlStatement = bodyContent.getString();
}
if (sqlStatement == null || sqlStatement.trim().length() == 0) {
throw new JspTagException(
Resources.getMessage("SQL_NO_STATEMENT"));
}
int result = 0;
try {
PreparedStatement ps = conn.prepareStatement(sqlStatement);
setParameters(ps, parameters);
result = ps.executeUpdate();
}
catch (Throwable e) {
throw new JspException(sqlStatement + ": " + e.getMessage(), e);
}
if (var != null)
pageContext.setAttribute(var, Integer.valueOf(result), scope);
return EVAL_PAGE;
}
/**
* Just rethrows the Throwable.
*/
public void doCatch(Throwable t) throws Throwable {
throw t;
}
/**
* Close the Connection, unless this action is used
* as part of a transaction.
*/
public void doFinally() {
if (conn != null && !isPartOfTransaction) {
try {
conn.close();
} catch (SQLException e) {
// Not much we can do
}
}
parameters = null;
conn = null;
}
//*********************************************************************
// Public utility methods
/**
* Called by nested parameter elements to add PreparedStatement
* parameter values.
*/
public void addSQLParameter(Object o) {
if (parameters == null) {
parameters = new ArrayList();
}
parameters.add(o);
}
//*********************************************************************
// Private utility methods
private Connection getConnection() throws JspException, SQLException {
// Fix: Add all other mechanisms
Connection conn = null;
isPartOfTransaction = false;
TransactionTagSupport parent = (TransactionTagSupport)
findAncestorWithClass(this, TransactionTagSupport.class);
if (parent != null) {
if (dataSourceSpecified) {
throw new JspTagException(
Resources.getMessage("ERROR_NESTED_DATASOURCE"));
}
conn = parent.getSharedConnection();
isPartOfTransaction = true;
} else {
if ((rawDataSource == null) && dataSourceSpecified) {
throw new JspException(
Resources.getMessage("SQL_DATASOURCE_NULL"));
}
DataSource dataSource = DataSourceUtil.getDataSource(rawDataSource,
pageContext);
try {
conn = dataSource.getConnection();
} catch (Exception ex) {
throw new JspException(
Resources.getMessage("DATASOURCE_INVALID",
ex.toString()));
}
}
return conn;
}
private void setParameters(PreparedStatement ps, List parameters)
throws SQLException
{
if (parameters != null) {
for (int i = 0; i < parameters.size(); i++) {
/* The first parameter has index 1. If a null
* is passed to setObject the parameter will be
* set to JDBC null so an explicit call to
* ps.setNull is not required.
*/
ps.setObject(i + 1, parameters.get(i));
}
}
}
}