org.springframework.web.servlet.tags.form.RadioButtonTag Maven / Gradle / Ivy
/*
* Copyright 2002-2007 the original author or authors.
*
* 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.springframework.web.servlet.tags.form;
import javax.servlet.jsp.JspException;
/**
* Databinding-aware JSP tag for rendering an HTML 'input'
* element with a 'type' of 'radio'.
*
* Rendered elements are marked as 'checked' if the configured
* {@link #setValue(Object) value} matches the {@link #getValue bound value}.
*
*
A typical usage pattern will involved multiple tag instances bound
* to the same property but with different values.
*
* @author Rob Harrop
* @since 2.0
*/
public class RadioButtonTag extends AbstractHtmlInputElementTag {
/**
* The value of the 'value' attribute.
*/
private Object value;
/**
* Set the value of the 'value' attribute.
* May be a runtime expression.
*/
public void setValue(Object value) {
this.value = value;
}
/**
* Get the value of the 'value' attribute.
* May be a runtime expression.
*/
protected Object getValue() {
return this.value;
}
/**
* Renders the 'input(radio)' element with the configured
* {@link #setValue(Object) value}. Marks the element as checked if the
* value matches the {@link #getValue bound value}.
*/
protected int writeTagContent(TagWriter tagWriter) throws JspException {
tagWriter.startTag("input");
writeDefaultAttributes(tagWriter);
tagWriter.writeAttribute("type", "radio");
Object value = getValue();
Object resolvedValue = evaluate("value", value);
tagWriter.writeAttribute("value", getDisplayString(resolvedValue, getPropertyEditor()));
if (SelectedValueComparator.isSelected(getBindStatus(), resolvedValue)) {
tagWriter.writeAttribute("checked", "checked");
}
tagWriter.endTag();
return EVAL_PAGE;
}
/**
* Return a unique ID for the bound name within the current PageContext.
*/
protected String autogenerateId() throws JspException {
return TagIdGenerator.nextId(getName(), this.pageContext);
}
}