AttributeDefinition.java

/*******************************************************************************
 * Copyright (c) 2004, 2008 John Krasnay and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     John Krasnay - initial API and implementation
 *******************************************************************************/
package net.sf.vex.dom;

import java.io.ObjectStreamException;
import java.io.Serializable;


/**
 * <code>AttributeDefinition</code> represents an attribute definition in a DTD.
 */
public class AttributeDefinition implements Comparable, Serializable {

    private String name;
    private Type type;
    private String defaultValue;
    private String[] values;
    private boolean required;
    private boolean fixed;

    /**
     * Enumeration of attribute types.
     */
    public static final class Type implements Serializable {

        private String s;

        public static final Type CDATA = new Type("CDATA");
        public static final Type ID = new Type("ID");
        public static final Type IDREF = new Type("IDREF");
        public static final Type IDREFS = new Type("IDREFS");
        public static final Type NMTOKEN = new Type("NMTOKEN");
        public static final Type NMTOKENS = new Type("NMTOKENS");
        public static final Type ENTITY = new Type("ENTITY");
        public static final Type ENTITIES = new Type("ENTITIES");
        public static final Type NOTATION = new Type("NOTATION");
        public static final Type ENUMERATION = new Type("ENUMERATION");

        private Type(String s) {
            this.s = s;
        }

        public static Type get(String s) {
            if (s.equals(CDATA.toString())) {
                return CDATA;
            } else if (s.equals(ID.toString())) {
                return ID;
            } else if (s.equals(IDREF.toString())) {
                return IDREF;
            } else if (s.equals(IDREFS.toString())) {
                return IDREFS;
            } else if (s.equals(NMTOKEN.toString())) {
                return NMTOKEN;
            } else if (s.equals(NMTOKENS.toString())) {
                return NMTOKENS;
            } else if (s.equals(ENTITY.toString())) {
                return ENTITY;
            } else if (s.equals(ENTITIES.toString())) {
                return ENTITIES;
            } else if (s.equals(NOTATION.toString())) {
                return NOTATION;
            } else if (s.equals(ENUMERATION.toString())) {
                return ENUMERATION;
            } else {
                throw new IllegalArgumentException(
                    "Attribute type '" + s + "' not recognized");
            }
        }

        public String toString() {
            return this.s;
        }
        
        /**
         * Serialization method, to ensure that we do not introduce new 
         * instances.
         */
        private Object readResolve() throws ObjectStreamException {
            return get(this.toString());
        }
    }


    /**
     * Class constructor.
     */
    public AttributeDefinition(
        String name, 
        Type type, 
        String defaultValue,
        String[] values,
        boolean required,
        boolean fixed) {
            
	this.name = name;
	this.type = type;
	this.defaultValue = defaultValue;
        this.values = values;
        this.required = required;
        this.fixed = fixed;
    }

    /**
     * Implements <code>Comparable.compareTo</code> to sort alphabetically
     * by name.
     *
     * @param other The attribute to which this one is to be compared.
     */
    public int compareTo(Object other) {
	return this.name.compareTo(((AttributeDefinition)other).name);
    }

    /**
     * Returns the attribute's type.
     */
    public Type getType() {
	return this.type;
    }

    /**
     * Returns the default value of the attribute. 
     */
    public String getDefaultValue() {
        return defaultValue;
    }

    /**
     * Returns true if the attribute value is fixed.
     */
    public boolean isFixed() {
        return fixed;
    }

    /**
     * Returns the name of the attribute.
     */
    public String getName() {
        return name;
    }

    /**
     * Returns true if the attribute is required.
     */
    public boolean isRequired() {
        return required;
    }

    /**
     * Returns an array of acceptable values for the attribute.
     * If null is returned, any value is acceptable for the attribute. 
     */
    public String[] getValues() {
        return values;
    }

}