org.springframework.web.servlet.tags.form.AbstractSingleCheckedElementTag Maven / Gradle / Ivy
/*
* Copyright 2002-2018 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
*
* https://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;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
/**
* Abstract base class to provide common methods for implementing databinding-aware
* JSP tags for rendering a single HTML '{@code input}' element with a
* '{@code type}' of '{@code checkbox}' or '{@code radio}'.
*
* @author Juergen Hoeller
* @since 2.5.2
*/
@SuppressWarnings("serial")
public abstract class AbstractSingleCheckedElementTag extends AbstractCheckedElementTag {
/**
* The value of the '{@code value}' attribute.
*/
@Nullable
private Object value;
/**
* The value of the '{@code label}' attribute.
*/
@Nullable
private Object label;
/**
* Set the value of the '{@code value}' attribute.
* May be a runtime expression.
*/
public void setValue(Object value) {
this.value = value;
}
/**
* Get the value of the '{@code value}' attribute.
*/
@Nullable
protected Object getValue() {
return this.value;
}
/**
* Set the value of the '{@code label}' attribute.
* May be a runtime expression.
*/
public void setLabel(Object label) {
this.label = label;
}
/**
* Get the value of the '{@code label}' attribute.
*/
@Nullable
protected Object getLabel() {
return this.label;
}
/**
* Renders the '{@code input(radio)}' element with the configured
* {@link #setValue(Object) value}. Marks the element as checked if the
* value matches the {@link #getValue bound value}.
*/
@Override
protected int writeTagContent(TagWriter tagWriter) throws JspException {
tagWriter.startTag("input");
String id = resolveId();
writeOptionalAttribute(tagWriter, "id", id);
writeOptionalAttribute(tagWriter, "name", getName());
writeOptionalAttributes(tagWriter);
writeTagDetails(tagWriter);
tagWriter.endTag();
Object resolvedLabel = evaluate("label", getLabel());
if (resolvedLabel != null) {
Assert.state(id != null, "Label id is required");
tagWriter.startTag("label");
tagWriter.writeAttribute("for", id);
tagWriter.appendValue(convertToDisplayString(resolvedLabel));
tagWriter.endTag();
}
return SKIP_BODY;
}
/**
* Write the details for the given primary tag:
* i.e. special attributes and the tag's value.
*/
protected abstract void writeTagDetails(TagWriter tagWriter) throws JspException;
}