port.org.bouncycastle.asn1.ASN1Enumerated Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of dss-model Show documentation
DSS Model contains the data model representation for DSS
There is a newer version: 6.0.d4j.2
package port.org.bouncycastle.asn1;

import java.io.IOException;
import java.math.BigInteger;

import port.org.bouncycastle.util.Arrays;

/**
 * Class representing the ASN.1 ENUMERATED type.
 */
public class ASN1Enumerated extends ASN1Primitive {

	byte[] bytes;

	/**
	 * return an enumerated from the passed in object
	 *
	 * @param obj
	 *            an ASN1Enumerated or an object that can be converted into one.
	 * @exception IllegalArgumentException
	 *                if the object cannot be converted.
	 * @return an ASN1Enumerated instance, or null.
	 */
	public static ASN1Enumerated getInstance(Object obj) {
		if ((obj == null) || (obj instanceof ASN1Enumerated)) {
			return (ASN1Enumerated) obj;
		}

		if (obj instanceof byte[]) {
			try {
				return (ASN1Enumerated) fromByteArray((byte[]) obj);
			} catch (Exception e) {
				throw new IllegalArgumentException("encoding error in getInstance: " + e.toString());
			}
		}

		throw new IllegalArgumentException("illegal object in getInstance: " + obj.getClass().getName());
	}

	/**
	 * return an Enumerated from a tagged object.
	 *
	 * @param obj
	 *            the tagged object holding the object we want
	 * @param explicit
	 *            true if the object is meant to be explicitly
	 *            tagged false otherwise.
	 * @exception IllegalArgumentException
	 *                if the tagged object cannot
	 *                be converted.
	 * @return an ASN1Enumerated instance, or null.
	 */
	public static ASN1Enumerated getInstance(ASN1TaggedObject obj, boolean explicit) {
		ASN1Primitive o = obj.getObject();

		if (explicit || (o instanceof ASN1Enumerated)) {
			return getInstance(o);
		} else {
			return fromOctetString(((ASN1OctetString) o).getOctets());
		}
	}

	/**
	 * Constructor from int.
	 *
	 * @param value
	 *            the value of this enumerated.
	 */
	public ASN1Enumerated(int value) {
		bytes = BigInteger.valueOf(value).toByteArray();
	}

	/**
	 * Constructor from BigInteger
	 *
	 * @param value
	 *            the value of this enumerated.
	 */
	public ASN1Enumerated(BigInteger value) {
		bytes = value.toByteArray();
	}

	/**
	 * Constructor from encoded BigInteger.
	 *
	 * @param bytes
	 *            the value of this enumerated as an encoded BigInteger (signed).
	 */
	public ASN1Enumerated(byte[] bytes) {
		this.bytes = bytes;
	}

	public BigInteger getValue() {
		return new BigInteger(bytes);
	}

	@Override
	boolean isConstructed() {
		return false;
	}

	@Override
	int encodedLength() {
		return 1 + StreamUtil.calculateBodyLength(bytes.length) + bytes.length;
	}

	@Override
	void encode(ASN1OutputStream out) throws IOException {
		out.writeEncoded(BERTags.ENUMERATED, bytes);
	}

	@Override
	boolean asn1Equals(ASN1Primitive o) {
		if (!(o instanceof ASN1Enumerated)) {
			return false;
		}

		ASN1Enumerated other = (ASN1Enumerated) o;

		return Arrays.areEqual(this.bytes, other.bytes);
	}

	@Override
	public int hashCode() {
		return Arrays.hashCode(bytes);
	}

	private static ASN1Enumerated[] cache = new ASN1Enumerated[12];

	static ASN1Enumerated fromOctetString(byte[] enc) {
		if (enc.length > 1) {
			return new ASN1Enumerated(Arrays.clone(enc));
		}

		if (enc.length == 0) {
			throw new IllegalArgumentException("ENUMERATED has zero length");
		}
		int value = enc[0] & 0xff;

		if (value >= cache.length) {
			return new ASN1Enumerated(Arrays.clone(enc));
		}

		ASN1Enumerated possibleMatch = cache[value];

		if (possibleMatch == null) {
			possibleMatch = cache[value] = new ASN1Enumerated(Arrays.clone(enc));
		}

		return possibleMatch;
	}

}