/*
* $Header: /home/cvs/jakarta-struts/src/share/org/apache/struts/util/LabelValueBean.java,v 1.10 2004/03/14 06:23:51 sraeburn Exp $
* $Revision: 1.10 $
* $Date: 2004/03/14 06:23:51 $
*
* Copyright 1999-2004 The Apache Software Foundation.
*
* 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.apache.struts.util;
import java.io.Serializable;
import java.util.Comparator;
/**
* A simple JavaBean to represent label-value pairs. This is most commonly used
* when constructing user interface elements which have a label to be displayed
* to the user, and a corresponding value to be returned to the server. One
* example is the <html:options> tag.
*
*
* Note: this class has a natural ordering that is inconsistent with equals.
*
*
* @version $Revision: 1.10 $ $Date: 2004/03/14 06:23:51 $
*/
public class LabelValueBean implements Comparable, Serializable {
/**
* Comparator that can be used for a case insensitive sort of
* LabelValueBean objects.
*/
public static final Comparator CASE_INSENSITIVE_ORDER = new Comparator() {
public int compare(Object o1, Object o2) {
String label1 = ((LabelValueBean) o1).getLabel();
String label2 = ((LabelValueBean) o2).getLabel();
return label1.compareToIgnoreCase(label2);
}
};
// ----------------------------------------------------------- Constructors
/**
* Default constructor.
*/
public LabelValueBean() {
super();
}
/**
* Construct an instance with the supplied property values.
*
* @param label The label to be displayed to the user.
* @param value The value to be returned to the server.
*/
public LabelValueBean(String label, String value) {
this.label = label;
this.value = value;
}
// ------------------------------------------------------------- Properties
/**
* The property which supplies the option label visible to the end user.
*/
private String label = null;
public String getLabel() {
return this.label;
}
public void setLabel(String label) {
this.label = label;
}
/**
* The property which supplies the value returned to the server.
*/
private String value = null;
public String getValue() {
return this.value;
}
public void setValue(String value) {
this.value = value;
}
// --------------------------------------------------------- Public Methods
/**
* Compare LabelValueBeans based on the label, because that's the human
* viewable part of the object.
* @see Comparable
*/
public int compareTo(Object o) {
// Implicitly tests for the correct type, throwing
// ClassCastException as required by interface
String otherLabel = ((LabelValueBean) o).getLabel();
return this.getLabel().compareTo(otherLabel);
}
/**
* Return a string representation of this object.
*/
public String toString() {
StringBuffer sb = new StringBuffer("LabelValueBean[");
sb.append(this.label);
sb.append(", ");
sb.append(this.value);
sb.append("]");
return (sb.toString());
}
/**
* LabelValueBeans are equal if their values are both null or equal.
* @see java.lang.Object#equals(java.lang.Object)
*/
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof LabelValueBean)) {
return false;
}
LabelValueBean bean = (LabelValueBean) obj;
int nil = (this.getValue() == null) ? 1 : 0;
nil += (bean.getValue() == null) ? 1 : 0;
if (nil == 2) {
return true;
} else if (nil == 1) {
return false;
} else {
return this.getValue().equals(bean.getValue());
}
}
/**
* The hash code is based on the object's value.
* @see java.lang.Object#hashCode()
*/
public int hashCode() {
return (this.getValue() == null) ? 17 : this.getValue().hashCode();
}
}
