/*
* 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 javax.servlet.jsp.JspException;
import org.springframework.util.Assert;
import org.springframework.util.ObjectUtils;
import org.springframework.util.StringUtils;
import org.springframework.web.servlet.support.BindStatus;
import org.springframework.web.util.TagUtils;
/**
* Convenient tag that allows one to supply a collection of objects
* that are to be rendered as '<code>option</code>' tags within a
* '<code>select</code>' tag.
*
* <p><i>Must</i> be used within a {@link SelectTag 'select' tag}.
*
* @author Rob Harrop
* @author Juergen Hoeller
* @author Scott Andrews
* @since 2.0
*/
public class OptionsTag extends AbstractHtmlElementTag {
/**
* The {@link java.util.Collection}, {@link java.util.Map} or array of
* objects used to generate the inner '<code>option</code>' tags.
*/
private Object items;
/**
* The name of the property mapped to the '<code>value</code>' attribute
* of the '<code>option</code>' tag.
*/
private String itemValue;
/**
* The name of the property mapped to the inner text of the
* '<code>option</code>' tag.
*/
private String itemLabel;
private String disabled;
/**
* Set the {@link java.util.Collection}, {@link java.util.Map} or array
* of objects used to generate the inner '<code>option</code>' tags.
* <p>Required when wishing to render '<code>option</code>' tags from an
* array, {@link java.util.Collection} or {@link java.util.Map}.
* <p>Typically a runtime expression.
*/
public void setItems(Object items) {
this.items = items;
}
/**
* Get the {@link java.util.Collection}, {@link java.util.Map} or array
* of objects used to generate the inner '<code>option</code>' tags.
* <p>Typically a runtime expression.
*/
protected Object getItems() {
return this.items;
}
/**
* Set the name of the property mapped to the '<code>value</code>'
* attribute of the '<code>option</code>' tag.
* <p>Required when wishing to render '<code>option</code>' tags from
* an array or {@link java.util.Collection}.
* <p>May be a runtime expression.
*/
public void setItemValue(String itemValue) {
Assert.hasText(itemValue, "'itemValue' must not be empty");
this.itemValue = itemValue;
}
/**
* Return the name of the property mapped to the '<code>value</code>'
* attribute of the '<code>option</code>' tag.
*/
protected String getItemValue() {
return this.itemValue;
}
/**
* Set the name of the property mapped to the label (inner text) of the
* '<code>option</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 name of the property mapped to the label (inner text) of the
* '<code>option</code>' tag.
* <p>May be a runtime expression.
*/
protected String getItemLabel() {
return this.itemLabel;
}
/**
* Set the value of the '<code>disabled</code>' attribute.
* <p>May be a runtime expression.
* @param disabled the value of the '<code>disabled</code>' attribute
*/
public void setDisabled(String disabled) {
this.disabled = disabled;
}
/**
* Get the value of the '<code>disabled</code>' attribute.
*/
protected String getDisabled() {
return this.disabled;
}
/**
* Is the current HTML tag disabled?
* @return <code>true</code> if this tag is disabled
*/
protected boolean isDisabled() throws JspException {
return evaluateBoolean("disabled", getDisabled());
}
@Override
protected int writeTagContent(TagWriter tagWriter) throws JspException {
assertUnderSelectTag();
Object items = getItems();
Object itemsObject = null;
if (items != null) {
itemsObject = (items instanceof String ? evaluate("items", items) : items);
} else {
Class<?> selectTagBoundType = ((SelectTag) findAncestorWithClass(this, SelectTag.class))
.getBindStatus().getValueType();
if (selectTagBoundType != null && selectTagBoundType.isEnum()) {
itemsObject = selectTagBoundType.getEnumConstants();
}
}
if (itemsObject != null) {
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);
OptionsWriter optionWriter = new OptionsWriter(itemsObject, valueProperty, labelProperty);
optionWriter.writeOptions(tagWriter);
}
return SKIP_BODY;
}
/**
* Appends a counter to a specified id,
* since we're dealing with multiple HTML elements.
*/
@Override
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 null;
}
private void assertUnderSelectTag() {
TagUtils.assertHasAncestorOfType(this, SelectTag.class, "options", "select");
}
@Override
protected BindStatus getBindStatus() {
return (BindStatus) this.pageContext.getAttribute(SelectTag.LIST_VALUE_PAGE_ATTRIBUTE);
}
/**
* Inner class that adapts OptionWriter for multiple options to be rendered.
*/
private class OptionsWriter extends OptionWriter {
public OptionsWriter(Object optionSource, String valueProperty, String labelProperty) {
super(optionSource, getBindStatus(), valueProperty, labelProperty, isHtmlEscape());
}
@Override
protected boolean isOptionDisabled() throws JspException {
return isDisabled();
}
@Override
protected void writeCommonAttributes(TagWriter tagWriter) throws JspException {
writeOptionalAttribute(tagWriter, "id", resolveId());
writeOptionalAttributes(tagWriter);
}
}
}
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