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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;

/**
 * A NULL object - use DERNull.INSTANCE for populating structures.
 */
public abstract class ASN1Null extends ASN1Primitive {

	/**
	 * Return an instance of ASN.1 NULL from the passed in object.
	 * 
	 * Accepted inputs:
	 * 

	 * null → null
	 * 
 {@link ASN1Null} object
	 * 
a byte[] containing ASN.1 NULL object
	 * 
	 * 
	 *
	 * @param o
	 *            object to be converted.
	 * @return an instance of ASN1Null, or null.
	 * @exception IllegalArgumentException
	 *                if the object cannot be converted.
	 */
	public static ASN1Null getInstance(Object o) {
		if (o instanceof ASN1Null) {
			return (ASN1Null) o;
		}

		if (o != null) {
			try {
				return ASN1Null.getInstance(ASN1Primitive.fromByteArray((byte[]) o));
			} catch (IOException e) {
				throw new IllegalArgumentException("failed to construct NULL from byte[]: " + e.getMessage());
			} catch (ClassCastException e) {
				throw new IllegalArgumentException("unknown object in getInstance(): " + o.getClass().getName());
			}
		}

		return null;
	}

	@Override
	public int hashCode() {
		return -1;
	}

	@Override
	boolean asn1Equals(ASN1Primitive o) {
		if (!(o instanceof ASN1Null)) {
			return false;
		}

		return true;
	}

	@Override
	abstract void encode(ASN1OutputStream out) throws IOException;

	@Override
	public String toString() {
		return "NULL";
	}

}