Java example source code file (CRLNumberExtension.java)

This example Java source code file (CRLNumberExtension.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

attribute, attributenameenumeration, biginteger, boolean, certattrset, crlnumberextension, deroutputstream, dervalue, ioexception, label, math, name, object, objectidentifier, string, util

The CRLNumberExtension.java Java example source code

/*
 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package sun.security.x509;

import java.io.IOException;
import java.io.OutputStream;
import java.math.BigInteger;
import java.util.Enumeration;

import sun.security.util.*;

/**
 * Represent the CRL Number Extension.
 *
 * <p>This extension, if present, conveys a monotonically increasing
 * sequence number for each CRL issued by a given CA through a specific
 * CA X.500 Directory entry or CRL distribution point. This extension
 * allows users to easily determine when a particular CRL supersedes
 * another CRL.
 *
 * @author Hemma Prafullchandra
 * @see Extension
 * @see CertAttrSet
 */
public class CRLNumberExtension extends Extension
implements CertAttrSet<String> {

    /**
     * Attribute name.
     */
    public static final String NAME = "CRLNumber";
    public static final String NUMBER = "value";

    private static final String LABEL = "CRL Number";

    private BigInteger crlNumber = null;
    private String extensionName;
    private String extensionLabel;

    // Encode this extension value
    private void encodeThis() throws IOException {
        if (crlNumber == null) {
            this.extensionValue = null;
            return;
        }
        DerOutputStream os = new DerOutputStream();
        os.putInteger(this.crlNumber);
        this.extensionValue = os.toByteArray();
    }

    /**
     * Create a CRLNumberExtension with the integer value .
     * The criticality is set to false.
     *
     * @param crlNum the value to be set for the extension.
     */
    public CRLNumberExtension(int crlNum) throws IOException {
        this(PKIXExtensions.CRLNumber_Id, false, BigInteger.valueOf(crlNum),
        NAME, LABEL);
    }

    /**
     * Create a CRLNumberExtension with the BigInteger value .
     * The criticality is set to false.
     *
     * @param crlNum the value to be set for the extension.
     */
    public CRLNumberExtension(BigInteger crlNum) throws IOException {
        this(PKIXExtensions.CRLNumber_Id, false, crlNum, NAME, LABEL);
    }

    /**
     * Creates the extension (also called by the subclass).
     */
    protected CRLNumberExtension(ObjectIdentifier extensionId,
        boolean isCritical, BigInteger crlNum, String extensionName,
        String extensionLabel) throws IOException {

        this.extensionId = extensionId;
        this.critical = isCritical;
        this.crlNumber = crlNum;
        this.extensionName = extensionName;
        this.extensionLabel = extensionLabel;
        encodeThis();
    }

    /**
     * Create the extension from the passed DER encoded value of the same.
     *
     * @param critical true if the extension is to be treated as critical.
     * @param value an array of DER encoded bytes of the actual value.
     * @exception ClassCastException if value is not an array of bytes
     * @exception IOException on error.
     */
    public CRLNumberExtension(Boolean critical, Object value)
    throws IOException {
        this(PKIXExtensions.CRLNumber_Id, critical, value, NAME, LABEL);
    }

    /**
     * Creates the extension (also called by the subclass).
     */
    protected CRLNumberExtension(ObjectIdentifier extensionId,
        Boolean critical, Object value, String extensionName,
        String extensionLabel) throws IOException {

        this.extensionId = extensionId;
        this.critical = critical.booleanValue();
        this.extensionValue = (byte[]) value;
        DerValue val = new DerValue(this.extensionValue);
        this.crlNumber = val.getBigInteger();
        this.extensionName = extensionName;
        this.extensionLabel = extensionLabel;
    }

    /**
     * Set the attribute value.
     */
    public void set(String name, Object obj) throws IOException {
        if (name.equalsIgnoreCase(NUMBER)) {
            if (!(obj instanceof BigInteger)) {
                throw new IOException("Attribute must be of type BigInteger.");
            }
            crlNumber = (BigInteger)obj;
        } else {
          throw new IOException("Attribute name not recognized by"
                                + " CertAttrSet:" + extensionName + ".");
        }
        encodeThis();
    }

    /**
     * Get the attribute value.
     */
    public BigInteger get(String name) throws IOException {
        if (name.equalsIgnoreCase(NUMBER)) {
            if (crlNumber == null) return null;
            else return crlNumber;
        } else {
          throw new IOException("Attribute name not recognized by"
                                + " CertAttrSet:" + extensionName + ".");
        }
    }

    /**
     * Delete the attribute value.
     */
    public void delete(String name) throws IOException {
        if (name.equalsIgnoreCase(NUMBER)) {
            crlNumber = null;
        } else {
          throw new IOException("Attribute name not recognized by"
                                + " CertAttrSet:" + extensionName + ".");
        }
        encodeThis();
    }

    /**
     * Returns a printable representation of the CRLNumberExtension.
     */
    public String toString() {
        String s = super.toString() + extensionLabel + ": " +
                   ((crlNumber == null) ? "" : Debug.toHexString(crlNumber))
                   + "\n";
        return (s);
    }

    /**
     * Write the extension to the DerOutputStream.
     *
     * @param out the DerOutputStream to write the extension to.
     * @exception IOException on encoding errors.
     */
    public void encode(OutputStream out) throws IOException {
       DerOutputStream  tmp = new DerOutputStream();
        encode(out, PKIXExtensions.CRLNumber_Id, true);
    }

    /**
     * Write the extension to the DerOutputStream.
     * (Also called by the subclass)
     */
    protected void encode(OutputStream out, ObjectIdentifier extensionId,
        boolean isCritical) throws IOException {

       DerOutputStream  tmp = new DerOutputStream();

       if (this.extensionValue == null) {
           this.extensionId = extensionId;
           this.critical = isCritical;
           encodeThis();
       }
       super.encode(tmp);
       out.write(tmp.toByteArray());
    }

    /**
     * Return an enumeration of names of attributes existing within this
     * attribute.
     */
    public Enumeration<String> getElements() {
        AttributeNameEnumeration elements = new AttributeNameEnumeration();
        elements.addElement(NUMBER);
        return (elements.elements());
    }

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