package org.bouncycastle.asn1.cms;

import org.bouncycastle.asn1.*;

public class Attribute
    implements DEREncodable
{
        private DERObjectIdentifier attrType;
        private ASN1Set             attrValues;

    /**
     * return an Attribute object from the given object.
     *
     * @param o the object we want converted.
     * @exception IllegalArgumentException if the object cannot be converted.
     */
        public static Attribute getInstance(
        Object o)
    {
                if (o == null || o instanceof Attribute)
        {
                        return (Attribute)o;
                }
                
                if (o instanceof ASN1Sequence)
        {
                        return new Attribute((ASN1Sequence)o);
                }

        throw new IllegalArgumentException("unknown object in factory");
        }
        
        public Attribute(
        ASN1Sequence seq)
    {
                attrType = (DERObjectIdentifier)seq.getObjectAt(0);
                attrValues = (ASN1Set)seq.getObjectAt(1);
        }

        public Attribute(
            DERObjectIdentifier attrType,
            ASN1Set             attrValues)
    {
                this.attrType = attrType;
                this.attrValues = attrValues;
        }

        public DERObjectIdentifier getAttrType()
    {
                return attrType;
        }
        
        public ASN1Set getAttrValues()
    {
                return attrValues;
        }

    /** 
     * <pre>
     * Attribute ::= SEQUENCE {
     *  attrType OBJECT IDENTIFIER,
     *  attrValues SET OF AttributeValue
     * }
     * </pre>
     */
        public DERObject getDERObject()
    {
                DEREncodableVector v = new DEREncodableVector();

                v.add(attrType);
                v.add(attrValues);

                return new DERSequence(v);
        }
}