/*
* Copyright 2002-2008 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 java.util.Collection;
import java.util.Iterator;
import java.util.Map;
import javax.servlet.jsp.JspException;
import org.springframework.beans.BeanWrapper;
import org.springframework.beans.PropertyAccessorFactory;
import org.springframework.util.Assert;
import org.springframework.util.ObjectUtils;
import org.springframework.util.StringUtils;
/**
* Abstract base class to provide common methods for implementing
* databinding-aware JSP tags for rendering <i>multiple</i>
* HTML '<code>input</code>' elements with a '<code>type</code>'
* of '<code>checkbox</code>' or '<code>radio</code>'.
*
* @author Juergen Hoeller
* @since 2.5.2
*/
public abstract class AbstractMultiCheckedElementTag extends AbstractCheckedElementTag {
/**
* The HTML '<code>span</code>' tag.
*/
private static final String SPAN_TAG = "span";
/**
* The {@link java.util.Collection}, {@link java.util.Map} or array of objects
* used to generate the '<code>input type="checkbox/radio"</code>' tags.
*/
private Object items;
/**
* The name of the property mapped to the '<code>value</code>' attribute
* of the '<code>input type="checkbox/radio"</code>' tag.
*/
private String itemValue;
/**
* The value to be displayed as part of the '<code>input type="checkbox/radio"</code>' tag.
*/
private String itemLabel;
/**
* The HTML element used to enclose the '<code>input type="checkbox/radio"</code>' tag.
*/
private String element = SPAN_TAG;
/**
* Delimiter to use between each '<code>input type="checkbox/radio"</code>' tags.
*/
private String delimiter;
/**
* Set the {@link java.util.Collection}, {@link java.util.Map} or array of objects
* used to generate the '<code>input type="checkbox/radio"</code>' tags.
* <p>Typically a runtime expression.
* @param items said items
*/
public void setItems(Object items) {
Assert.notNull(items, "'items' must not be null");
this.items = items;
}
/**
* Get the {@link java.util.Collection}, {@link java.util.Map} or array of objects
* used to generate the '<code>input type="checkbox/radio"</code>' tags.
*/
protected Object getItems() {
return this.items;
}
/**
* Set the name of the property mapped to the '<code>value</code>' attribute
* of the '<code>input type="checkbox/radio"</code>' tag.
* <p>May be a runtime expression.
*/
public void setItemValue(String itemValue) {
Assert.hasText(itemValue, "'itemValue' must not be empty");
this.itemValue = itemValue;
}
protected String getItemValue() {
return this.itemValue;
}
/**
* Set the value to be displayed as part
* of the '<code>input type="checkbox/radio"</code>' tag.
* <p>May be a runtime expression.
*/
public void setItemLabel(String itemLabel) {
Assert.hasText(itemLabel, "'itemLabel' must not be empty");
this.itemLabel = itemLabel;
}
/**
* Get the value to be displayed as part
* of the '<code>input type="checkbox/radio"</code>' tag.
*/
protected String getItemLabel() {
return this.itemLabel;
}
/**
* Set the delimiter to be used between each
* '<code>input type="checkbox/radio"</code>' tag.
* <p>By default, there is <em>no</em> delimiter.
*/
public void setDelimiter(String delimiter) {
this.delimiter = delimiter;
}
/**
* Return the delimiter to be used between each
* '<code>input type="radio"</code>' tag.
*/
public String getDelimiter() {
return this.delimiter;
}
/**
* Set the HTML element used to enclose the
* '<code>input type="checkbox/radio"</code>' tag.
* <p>Defaults to an HTML '<code><span/></code>' tag.
*/
public void setElement(String element) {
Assert.hasText(element, "'element' cannot be null or blank");
this.element = element;
}
/**
* Get the HTML element used to enclose
* '<code>input type="checkbox/radio"</code>' tag.
*/
public String getElement() {
return this.element;
}
/**
* Appends a counter to a specified id as well,
* since we're dealing with multiple HTML elements.
*/
protected String resolveId() throws JspException {
Object id = evaluate("id", getId());
if (id != null) {
String idString = id.toString();
return (StringUtils.hasText(idString) ? TagIdGenerator.nextId(idString, this.pageContext) : null);
}
return autogenerateId();
}
/**
* Renders the '<code>input type="radio"</code>' element with the configured
* {@link #setItems(Object)} values. Marks the element as checked if the
* value matches the bound value.
*/
protected int writeTagContent(TagWriter tagWriter) throws JspException {
Object items = getItems();
Object itemsObject = (items instanceof String ? evaluate("items", (String) items) : items);
String itemValue = getItemValue();
String itemLabel = getItemLabel();
String valueProperty =
(itemValue != null ? ObjectUtils.getDisplayString(evaluate("itemValue", itemValue)) : null);
String labelProperty =
(itemLabel != null ? ObjectUtils.getDisplayString(evaluate("itemLabel", itemLabel)) : null);
if (itemsObject == null) {
throw new IllegalArgumentException("Attribute 'items' is required and must be a Collection, an Array or a Map");
}
if (itemsObject.getClass().isArray()) {
Object[] itemsArray = (Object[]) itemsObject;
for (int i = 0; i < itemsArray.length; i++) {
Object item = itemsArray[i];
writeObjectEntry(tagWriter, valueProperty, labelProperty, item, i);
}
}
else if (itemsObject instanceof Collection) {
final Collection optionCollection = (Collection) itemsObject;
int itemIndex = 0;
for (Iterator it = optionCollection.iterator(); it.hasNext(); itemIndex++) {
Object item = it.next();
writeObjectEntry(tagWriter, valueProperty, labelProperty, item, itemIndex);
}
}
else if (itemsObject instanceof Map) {
final Map optionMap = (Map) itemsObject;
int itemIndex = 0;
for (Iterator it = optionMap.entrySet().iterator(); it.hasNext(); itemIndex++) {
Map.Entry entry = (Map.Entry) it.next();
writeMapEntry(tagWriter, valueProperty, labelProperty, entry, itemIndex);
}
}
else {
throw new IllegalArgumentException("Attribute 'items' must be a Collection, an Array or a Map");
}
return SKIP_BODY;
}
private void writeObjectEntry(TagWriter tagWriter, String valueProperty,
String labelProperty, Object item, int itemIndex) throws JspException {
BeanWrapper wrapper = PropertyAccessorFactory.forBeanPropertyAccess(item);
Object renderValue = (valueProperty != null ? wrapper.getPropertyValue(valueProperty) : item);
Object renderLabel = (labelProperty != null ? wrapper.getPropertyValue(labelProperty) : item);
writeElementTag(tagWriter, item, renderValue, renderLabel, itemIndex);
}
private void writeMapEntry(TagWriter tagWriter, String valueProperty,
String labelProperty, Map.Entry entry, int itemIndex) throws JspException {
Object mapKey = entry.getKey();
Object mapValue = entry.getValue();
BeanWrapper mapKeyWrapper = PropertyAccessorFactory.forBeanPropertyAccess(mapKey);
BeanWrapper mapValueWrapper = PropertyAccessorFactory.forBeanPropertyAccess(mapValue);
Object renderValue = (valueProperty != null ?
mapKeyWrapper.getPropertyValue(valueProperty) : mapKey.toString());
Object renderLabel = (labelProperty != null ?
mapValueWrapper.getPropertyValue(labelProperty) : mapValue.toString());
writeElementTag(tagWriter, mapKey, renderValue, renderLabel, itemIndex);
}
private void writeElementTag(TagWriter tagWriter, Object item, Object value, Object label, int itemIndex)
throws JspException {
tagWriter.startTag(getElement());
if (itemIndex > 0) {
Object resolvedDelimiter = evaluate("delimiter", getDelimiter());
if (resolvedDelimiter != null) {
tagWriter.appendValue(resolvedDelimiter.toString());
}
}
tagWriter.startTag("input");
String id = resolveId();
writeOptionalAttribute(tagWriter, "id", id);
writeOptionalAttribute(tagWriter, "name", getName());
writeOptionalAttributes(tagWriter);
tagWriter.writeAttribute("type", getInputType());
renderFromValue(item, value, tagWriter);
tagWriter.endTag();
tagWriter.startTag("label");
tagWriter.writeAttribute("for", id);
tagWriter.appendValue(label.toString());
tagWriter.endTag();
tagWriter.endTag();
}
/**
* Return the type of the HTML input element to generate:
* "checkbox" or "radio".
*/
protected abstract String getInputType();
}