/*
* $Id: DefineTag.java 471754 2006-11-06 14:55:09Z husted $
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.struts.taglib.bean;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.struts.taglib.TagUtils;
import org.apache.struts.util.MessageResources;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.BodyTagSupport;
/**
* Define a scripting variable based on the value(s) of the specified bean
* property.
*
* @version $Rev: 471754 $ $Date: 2005-06-15 12:16:32 -0400 (Wed, 15 Jun 2005)
* $
*/
public class DefineTag extends BodyTagSupport {
/**
* Commons logging instance.
*/
private static final Log log = LogFactory.getLog(DefineTag.class);
// ---------------------------------------------------- Protected variables
/**
* The message resources for this package.
*/
protected static MessageResources messages =
MessageResources.getMessageResources(
"org.apache.struts.taglib.bean.LocalStrings");
/**
* The body content of this tag (if any).
*/
protected String body = null;
// ------------------------------------------------------------- Properties
/**
* The name of the scripting variable that will be exposed as a page scope
* attribute.
*/
protected String id = null;
/**
* The name of the bean owning the property to be exposed.
*/
protected String name = null;
/**
* The name of the property to be retrieved.
*/
protected String property = null;
/**
* The scope within which to search for the specified bean.
*/
protected String scope = null;
/**
* The scope within which the newly defined bean will be creatd.
*/
protected String toScope = null;
/**
* The fully qualified Java class name of the value to be exposed.
*/
protected String type = null;
/**
* The (String) value to which the defined bean will be set.
*/
protected String value = null;
public String getId() {
return (this.id);
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return (this.name);
}
public void setName(String name) {
this.name = name;
}
public String getProperty() {
return (this.property);
}
public void setProperty(String property) {
this.property = property;
}
public String getScope() {
return (this.scope);
}
public void setScope(String scope) {
this.scope = scope;
}
public String getToScope() {
return (this.toScope);
}
public void setToScope(String toScope) {
this.toScope = toScope;
}
public String getType() {
return (this.type);
}
public void setType(String type) {
this.type = type;
}
public String getValue() {
return (this.value);
}
public void setValue(String value) {
this.value = value;
}
// --------------------------------------------------------- Public Methods
/**
* Check if we need to evaluate the body of the tag
*
* @throws JspException if a JSP exception has occurred
*/
public int doStartTag() throws JspException {
return (EVAL_BODY_TAG);
}
/**
* Save the body content of this tag (if any), or throw a JspException if
* the value was already defined.
*
* @throws JspException if value was defined by an attribute
*/
public int doAfterBody() throws JspException {
if (bodyContent != null) {
body = bodyContent.getString();
if (body != null) {
body = body.trim();
}
if (body.length() < 1) {
body = null;
}
}
return (SKIP_BODY);
}
/**
* Retrieve the required property and expose it as a scripting variable.
*
* @throws JspException if a JSP exception has occurred
*/
public int doEndTag() throws JspException {
// Enforce restriction on ways to declare the new value
int n = 0;
if (this.body != null) {
n++;
}
if (this.name != null) {
n++;
}
if (this.value != null) {
n++;
}
if (n > 1) {
JspException e =
new JspException(messages.getMessage("define.value", id));
TagUtils.getInstance().saveException(pageContext, e);
throw e;
}
// Retrieve the required property value
Object value = this.value;
if ((value == null) && (name != null)) {
value =
TagUtils.getInstance().lookup(pageContext, name, property, scope);
}
if ((value == null) && (body != null)) {
value = body;
}
if (value == null) {
JspException e =
new JspException(messages.getMessage("define.null", id));
TagUtils.getInstance().saveException(pageContext, e);
throw e;
}
// Expose this value as a scripting variable
int inScope = PageContext.PAGE_SCOPE;
try {
if (toScope != null) {
inScope = TagUtils.getInstance().getScope(toScope);
}
} catch (JspException e) {
log.warn("toScope was invalid name so we default to PAGE_SCOPE", e);
}
pageContext.setAttribute(id, value, inScope);
// Continue processing this page
return (EVAL_PAGE);
}
/**
* Release all allocated resources.
*/
public void release() {
super.release();
body = null;
id = null;
name = null;
property = null;
scope = null;
toScope = "page";
type = null;
value = null;
}
}