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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

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 * 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,

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 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package sun.security.x509;

import java.io.IOException;

import java.io.OutputStream;

import java.util.*;

import sun.security.util.*;

/**

 * Represent the Policy Mappings Extension.

 *

 * This extension, if present, identifies the certificate policies considered

 * identical between the issuing and the subject CA.

 * <p>Extensions are addiitonal attributes which can be inserted in a X509

 * v3 certificate. For example a "Driving License Certificate" could have

 * the driving license number as a extension.

 *

 * <p>Extensions are represented as a sequence of the extension identifier

 * (Object Identifier), a boolean flag stating whether the extension is to

 * be treated as being critical and the extension value itself (this is again

 * a DER encoding of the extension value).

 *

 * @author Amit Kapoor

 * @author Hemma Prafullchandra

 * @see Extension

 * @see CertAttrSet

 */

public class PolicyMappingsExtension extends Extension

implements CertAttrSet<String> {

    /**

     * Identifier for this attribute, to be used with the

     * get, set, delete methods of Certificate, x509 type.

     */

    public static final String IDENT = "x509.info.extensions.PolicyMappings";

    /**

     * Attribute names.

     */

    public static final String NAME = "PolicyMappings";

    public static final String MAP = "map";

    // Private data members

    private List<CertificatePolicyMap> maps;

    // Encode this extension value

    private void encodeThis() throws IOException {

        if (maps == null || maps.isEmpty()) {

            this.extensionValue = null;

            return;

        }

        DerOutputStream os = new DerOutputStream();

        DerOutputStream tmp = new DerOutputStream();

        for (CertificatePolicyMap map : maps) {

            map.encode(tmp);

        }

        os.write(DerValue.tag_Sequence, tmp);

        this.extensionValue = os.toByteArray();

    }

    /**

     * Create a PolicyMappings with the List of CertificatePolicyMap.

     *

     * @param maps the List of CertificatePolicyMap.

     */

    public PolicyMappingsExtension(List<CertificatePolicyMap> maps)

            throws IOException {

        this.maps = maps;

        this.extensionId = PKIXExtensions.PolicyMappings_Id;

        this.critical = true;

        encodeThis();

    }

    /**

     * Create a default PolicyMappingsExtension.

     */

    public PolicyMappingsExtension() {

        extensionId = PKIXExtensions.PolicyMappings_Id;

        critical = true;

        maps = Collections.<CertificatePolicyMap>emptyList();

    }

    /**

     * Create the extension from the passed DER encoded value.

     *

     * @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 PolicyMappingsExtension(Boolean critical, Object value)

    throws IOException {

        this.extensionId = PKIXExtensions.PolicyMappings_Id;

        this.critical = critical.booleanValue();

        this.extensionValue = (byte[]) value;

        DerValue val = new DerValue(this.extensionValue);

        if (val.tag != DerValue.tag_Sequence) {

            throw new IOException("Invalid encoding for " +

                                  "PolicyMappingsExtension.");

        }

        maps = new ArrayList<CertificatePolicyMap>();

        while (val.data.available() != 0) {

            DerValue seq = val.data.getDerValue();

            CertificatePolicyMap map = new CertificatePolicyMap(seq);

            maps.add(map);

        }

    }

    /**

     * Returns a printable representation of the policy map.

     */

    public String toString() {

        if (maps == null) return "";

        String s = super.toString() + "PolicyMappings [\n"

                 + maps.toString() + "]\n";

        return (s);

    }

    /**

     * 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.PolicyMappings_Id;

            critical = true;

            encodeThis();

        }

        super.encode(tmp);

        out.write(tmp.toByteArray());

    }

    /**

     * Set the attribute value.

     */

    @SuppressWarnings("unchecked") // Checked with instanceof

    public void set(String name, Object obj) throws IOException {

        if (name.equalsIgnoreCase(MAP)) {

            if (!(obj instanceof List)) {

              throw new IOException("Attribute value should be of" +

                                    " type List.");

            }

            maps = (List<CertificatePolicyMap>)obj;

        } else {

          throw new IOException("Attribute name not recognized by " +

                        "CertAttrSet:PolicyMappingsExtension.");

        }

        encodeThis();

    }

    /**

     * Get the attribute value.

     */

    public List<CertificatePolicyMap> get(String name) throws IOException {

        if (name.equalsIgnoreCase(MAP)) {

            return (maps);

        } else {

          throw new IOException("Attribute name not recognized by " +

                        "CertAttrSet:PolicyMappingsExtension.");

        }

    }

    /**

     * Delete the attribute value.

     */

    public void delete(String name) throws IOException {

        if (name.equalsIgnoreCase(MAP)) {

            maps = null;

        } else {

          throw new IOException("Attribute name not recognized by " +

                        "CertAttrSet:PolicyMappingsExtension.");

        }

        encodeThis();

    }

    /**

     * Return an enumeration of names of attributes existing within this

     * attribute.

     */

    public Enumeration<String> getElements () {

        AttributeNameEnumeration elements = new AttributeNameEnumeration();

        elements.addElement(MAP);

        return elements.elements();

    }

    /**

     * Return the name of this attribute.

     */

    public String getName () {

        return (NAME);

    }

}