Java example source code file (CertificateIssuerExtension.java)

This example Java source code file (CertificateIssuerExtension.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, certattrset\:certificateissuer, certificateissuerextension, deroutputstream, dervalue, generalnames, ioexception, object, string, util

The CertificateIssuerExtension.java Java example source code

/*
 * Copyright (c) 2003, 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.util.Enumeration;

import sun.security.util.DerValue;
import sun.security.util.DerOutputStream;

/**
 * Represents the CRL Certificate Issuer Extension (OID = 2.5.29.29).
 * <p>
 * The CRL certificate issuer extension identifies the certificate issuer
 * associated with an entry in an indirect CRL, i.e. a CRL that has the
 * indirectCRL indicator set in its issuing distribution point extension. If
 * this extension is not present on the first entry in an indirect CRL, the
 * certificate issuer defaults to the CRL issuer. On subsequent entries
 * in an indirect CRL, if this extension is not present, the certificate
 * issuer for the entry is the same as that for the preceding entry.
 * <p>
 * If used by conforming CRL issuers, this extension is always
 * critical.  If an implementation ignored this extension it could not
 * correctly attribute CRL entries to certificates.  PKIX (RFC 3280)
 * RECOMMENDS that implementations recognize this extension.
 * <p>
 * The ASN.1 definition for this is:
 * <pre>
 * id-ce-certificateIssuer   OBJECT IDENTIFIER ::= { id-ce 29 }
 *
 * certificateIssuer ::=     GeneralNames
 * </pre>
 *
 * @author Anne Anderson
 * @author Sean Mullan
 * @since 1.5
 * @see Extension
 * @see CertAttrSet
 */
public class CertificateIssuerExtension extends Extension
    implements CertAttrSet<String> {

    /**
     * Attribute names.
     */
    public static final String NAME = "CertificateIssuer";
    public static final String ISSUER = "issuer";

    private GeneralNames names;

    /**
     * Encode this extension
     */
    private void encodeThis() throws IOException {
        if (names == null || names.isEmpty()) {
            this.extensionValue = null;
            return;
        }
        DerOutputStream os = new DerOutputStream();
        names.encode(os);
        this.extensionValue = os.toByteArray();
    }

    /**
     * Create a CertificateIssuerExtension containing the specified issuer name.
     * Criticality is automatically set to true.
     *
     * @param issuer the certificate issuer
     * @throws IOException on error
     */
    public CertificateIssuerExtension(GeneralNames issuer) throws IOException {
        this.extensionId = PKIXExtensions.CertificateIssuer_Id;
        this.critical = true;
        this.names = issuer;
        encodeThis();
    }

    /**
     * Create a CertificateIssuerExtension from the specified 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
     * @throws ClassCastException if value is not an array of bytes
     * @throws IOException on error
     */
    public CertificateIssuerExtension(Boolean critical, Object value)
        throws IOException {
        this.extensionId = PKIXExtensions.CertificateIssuer_Id;
        this.critical = critical.booleanValue();

        this.extensionValue = (byte[]) value;
        DerValue val = new DerValue(this.extensionValue);
        this.names = new GeneralNames(val);
    }

    /**
     * Set the attribute value.
     *
     * @throws IOException on error
     */
    public void set(String name, Object obj) throws IOException {
        if (name.equalsIgnoreCase(ISSUER)) {
            if (!(obj instanceof GeneralNames)) {
                throw new IOException("Attribute value must be of type " +
                    "GeneralNames");
            }
            this.names = (GeneralNames)obj;
        } else {
            throw new IOException("Attribute name not recognized by " +
                "CertAttrSet:CertificateIssuer");
        }
        encodeThis();
    }

    /**
     * Gets the attribute value.
     *
     * @throws IOException on error
     */
    public GeneralNames get(String name) throws IOException {
        if (name.equalsIgnoreCase(ISSUER)) {
            return names;
        } else {
            throw new IOException("Attribute name not recognized by " +
                "CertAttrSet:CertificateIssuer");
        }
    }

    /**
     * Deletes the attribute value.
     *
     * @throws IOException on error
     */
    public void delete(String name) throws IOException {
        if (name.equalsIgnoreCase(ISSUER)) {
            names = null;
        } else {
            throw new IOException("Attribute name not recognized by " +
                "CertAttrSet:CertificateIssuer");
        }
        encodeThis();
    }

    /**
     * Returns a printable representation of the certificate issuer.
     */
    public String toString() {
        return super.toString() + "Certificate Issuer [\n" +
            String.valueOf(names) + "]\n";
    }

    /**
     * Write the extension to the OutputStream.
     *
     * @param out the OutputStream to write the extension to
     * @exception IOException on encoding errors
     */
    public void encode(OutputStream out) throws IOException {
        DerOutputStream  tmp = new DerOutputStream();
        if (extensionValue == null) {
            extensionId = PKIXExtensions.CertificateIssuer_Id;
            critical = true;
            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(ISSUER);
        return elements.elements();
    }

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