/*
* $Id: SelectTag.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.html;
import org.apache.commons.beanutils.BeanUtils;
import org.apache.struts.taglib.TagUtils;
import org.apache.struts.util.MessageResources;
import javax.servlet.jsp.JspException;
import java.lang.reflect.InvocationTargetException;
/**
* Custom tag that represents an HTML select element, associated with a bean
* property specified by our attributes. This tag must be nested inside a
* form tag.
*
* @version $Rev: 471754 $ $Date: 2004-10-16 12:38:42 -0400 (Sat, 16 Oct 2004)
* $
*/
public class SelectTag extends BaseHandlerTag {
/**
* The message resources for this package.
*/
protected static MessageResources messages =
MessageResources.getMessageResources(Constants.Package
+ ".LocalStrings");
// ----------------------------------------------------- Instance Variables
/**
* The actual values we will match against, calculated in doStartTag().
*/
protected String[] match = null;
/**
* Should multiple selections be allowed. Any non-null value will trigger
* rendering this.
*/
protected String multiple = null;
/**
* The name of the bean containing our underlying property.
*/
protected String name = Constants.BEAN_KEY;
/**
* The property name we are associated with.
*/
protected String property = null;
/**
* The saved body content of this tag.
*/
protected String saveBody = null;
/**
* How many available options should be displayed when this element is
* rendered?
*/
protected String size = null;
/**
* The value to compare with for marking an option selected.
*/
protected String value = null;
public String getMultiple() {
return (this.multiple);
}
public void setMultiple(String multiple) {
this.multiple = multiple;
}
public String getName() {
return (this.name);
}
public void setName(String name) {
this.name = name;
}
public String getSize() {
return (this.size);
}
public void setSize(String size) {
this.size = size;
}
// ------------------------------------------------------------- Properties
/**
* Does the specified value match one of those we are looking for?
*
* @param value Value to be compared.
*/
public boolean isMatched(String value) {
if ((this.match == null) || (value == null)) {
return false;
}
for (int i = 0; i < this.match.length; i++) {
if (value.equals(this.match[i])) {
return true;
}
}
return false;
}
/**
* Return the property name.
*/
public String getProperty() {
return (this.property);
}
/**
* Set the property name.
*
* @param property The new property name
*/
public void setProperty(String property) {
this.property = property;
}
/**
* Return the comparison value.
*/
public String getValue() {
return (this.value);
}
/**
* Set the comparison value.
*
* @param value The new comparison value
*/
public void setValue(String value) {
this.value = value;
}
// --------------------------------------------------------- Public Methods
/**
* Render the beginning of this select tag. <p> Support for indexed
* property since Struts 1.1
*
* @throws JspException if a JSP exception has occurred
*/
public int doStartTag() throws JspException {
TagUtils.getInstance().write(pageContext, renderSelectStartElement());
// Store this tag itself as a page attribute
pageContext.setAttribute(Constants.SELECT_KEY, this);
this.calculateMatchValues();
return (EVAL_BODY_TAG);
}
/**
* Create an appropriate select start element based on our parameters.
*
* @throws JspException
* @since Struts 1.1
*/
protected String renderSelectStartElement()
throws JspException {
StringBuffer results = new StringBuffer("<select");
prepareAttribute(results, "name", prepareName());
prepareAttribute(results, "accesskey", getAccesskey());
if (multiple != null) {
results.append(" multiple=\"multiple\"");
}
prepareAttribute(results, "size", getSize());
prepareAttribute(results, "tabindex", getTabindex());
results.append(prepareEventHandlers());
results.append(prepareStyles());
prepareOtherAttributes(results);
results.append(">");
return results.toString();
}
/**
* Calculate the match values we will actually be using.
*
* @throws JspException
*/
private void calculateMatchValues()
throws JspException {
if (this.value != null) {
this.match = new String[1];
this.match[0] = this.value;
} else {
Object bean =
TagUtils.getInstance().lookup(pageContext, name, null);
if (bean == null) {
JspException e =
new JspException(messages.getMessage("getter.bean", name));
TagUtils.getInstance().saveException(pageContext, e);
throw e;
}
try {
this.match = BeanUtils.getArrayProperty(bean, property);
if (this.match == null) {
this.match = new String[0];
}
} catch (IllegalAccessException e) {
TagUtils.getInstance().saveException(pageContext, e);
throw new JspException(messages.getMessage("getter.access",
property, name));
} catch (InvocationTargetException e) {
Throwable t = e.getTargetException();
TagUtils.getInstance().saveException(pageContext, t);
throw new JspException(messages.getMessage("getter.result",
property, t.toString()));
} catch (NoSuchMethodException e) {
TagUtils.getInstance().saveException(pageContext, e);
throw new JspException(messages.getMessage("getter.method",
property, name));
}
}
}
/**
* Save any body content of this tag, which will generally be the
* option(s) representing the values displayed to the user.
*
* @throws JspException if a JSP exception has occurred
*/
public int doAfterBody() throws JspException {
if (bodyContent != null) {
String value = bodyContent.getString();
if (value == null) {
value = "";
}
this.saveBody = value.trim();
}
return (SKIP_BODY);
}
/**
* Render the end of this form.
*
* @throws JspException if a JSP exception has occurred
*/
public int doEndTag() throws JspException {
// Remove the page scope attributes we created
pageContext.removeAttribute(Constants.SELECT_KEY);
// Render a tag representing the end of our current form
StringBuffer results = new StringBuffer();
if (saveBody != null) {
results.append(saveBody);
saveBody = null;
}
results.append("</select>");
TagUtils.getInstance().write(pageContext, results.toString());
return (EVAL_PAGE);
}
/**
* Prepare the name element
*
* @return The element name.
*/
protected String prepareName()
throws JspException {
if (property == null) {
return null;
}
// * @since Struts 1.1
if (indexed) {
StringBuffer results = new StringBuffer();
prepareIndex(results, name);
results.append(property);
return results.toString();
}
return property;
}
/**
* Release any acquired resources.
*/
public void release() {
super.release();
match = null;
multiple = null;
name = Constants.BEAN_KEY;
property = null;
saveBody = null;
size = null;
value = null;
}
}