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

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 * 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

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 * accompanied this code).

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 * 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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 */

package java.security;

import java.io.Serializable;

import java.util.*;

/**

 * <p>This class represents identities: real-world objects such as people,

 * companies or organizations whose identities can be authenticated using

 * their public keys. Identities may also be more abstract (or concrete)

 * constructs, such as daemon threads or smart cards.

 *

 * <p>All Identity objects have a name and a public key. Names are

 * immutable. Identities may also be scoped. That is, if an Identity is

 * specified to have a particular scope, then the name and public

 * key of the Identity are unique within that scope.

 *

 * <p>An Identity also has a set of certificates (all certifying its own

 * public key). The Principal names specified in these certificates need

 * not be the same, only the key.

 *

 * <p>An Identity can be subclassed, to include postal and email addresses,

 * telephone numbers, images of faces and logos, and so on.

 *

 * @see IdentityScope

 * @see Signer

 * @see Principal

 *

 * @author Benjamin Renaud

 * @since 1.1

 * @deprecated This class is no longer used. Its functionality has been

 * replaced by {@code java.security.KeyStore}, the

 * {@code java.security.cert} package, and

 * {@code java.security.Principal}.

 */

@Deprecated(since="1.2")

public abstract class Identity implements Principal, Serializable {

    /** use serialVersionUID from JDK 1.1.x for interoperability */

    private static final long serialVersionUID = 3609922007826600659L;

    /**

     * The name for this identity.

     *

     * @serial

     */

    private String name;

    /**

     * The public key for this identity.

     *

     * @serial

     */

    private PublicKey publicKey;

    /**

     * Generic, descriptive information about the identity.

     *

     * @serial

     */

    String info = "No further information available.";

    /**

     * The scope of the identity.

     *

     * @serial

     */

    IdentityScope scope;

    /**

     * The certificates for this identity.

     *

     * @serial

     */

    Vector<Certificate> certificates;

    /**

     * Constructor for serialization only.

     */

    protected Identity() {

        this("restoring...");

    }

    /**

     * Constructs an identity with the specified name and scope.

     *

     * @param name the identity name.

     * @param scope the scope of the identity.

     *

     * @exception KeyManagementException if there is already an identity

     * with the same name in the scope.

     */

    public Identity(String name, IdentityScope scope) throws

    KeyManagementException {

        this(name);

        if (scope != null) {

            scope.addIdentity(this);

        }

        this.scope = scope;

    }

    /**

     * Constructs an identity with the specified name and no scope.

     *

     * @param name the identity name.

     */

    public Identity(String name) {

        this.name = name;

    }

    /**

     * Returns this identity's name.

     *

     * @return the name of this identity.

     */

    public final String getName() {

        return name;

    }

    /**

     * Returns this identity's scope.

     *

     * @return the scope of this identity.

     */

    public final IdentityScope getScope() {

        return scope;

    }

    /**

     * Returns this identity's public key.

     *

     * @return the public key for this identity.

     *

     * @see #setPublicKey

     */

    public PublicKey getPublicKey() {

        return publicKey;

    }

    /**

     * Sets this identity's public key. The old key and all of this

     * identity's certificates are removed by this operation.

     *

     * <p>First, if there is a security manager, its {@code checkSecurityAccess}

     * method is called with {@code "setIdentityPublicKey"}

     * as its argument to see if it's ok to set the public key.

     *

     * @param key the public key for this identity.

     *

     * @exception KeyManagementException if another identity in the

     * identity's scope has the same public key, or if another exception occurs.

     *

     * @exception  SecurityException  if a security manager exists and its

     * {@code checkSecurityAccess} method doesn't allow

     * setting the public key.

     *

     * @see #getPublicKey

     * @see SecurityManager#checkSecurityAccess

     */

    /* Should we throw an exception if this is already set? */

    public void setPublicKey(PublicKey key) throws KeyManagementException {

        check("setIdentityPublicKey");

        this.publicKey = key;

        certificates = new Vector<>();

    }

    /**

     * Specifies a general information string for this identity.

     *

     * <p>First, if there is a security manager, its {@code checkSecurityAccess}

     * method is called with {@code "setIdentityInfo"}

     * as its argument to see if it's ok to specify the information string.

     *

     * @param info the information string.

     *

     * @exception  SecurityException  if a security manager exists and its

     * {@code checkSecurityAccess} method doesn't allow

     * setting the information string.

     *

     * @see #getInfo

     * @see SecurityManager#checkSecurityAccess

     */

    public void setInfo(String info) {

        check("setIdentityInfo");

        this.info = info;

    }

    /**

     * Returns general information previously specified for this identity.

     *

     * @return general information about this identity.

     *

     * @see #setInfo

     */

    public String getInfo() {

        return info;

    }

    /**

     * Adds a certificate for this identity. If the identity has a public

     * key, the public key in the certificate must be the same, and if

     * the identity does not have a public key, the identity's

     * public key is set to be that specified in the certificate.

     *

     * <p>First, if there is a security manager, its {@code checkSecurityAccess}

     * method is called with {@code "addIdentityCertificate"}

     * as its argument to see if it's ok to add a certificate.

     *

     * @param certificate the certificate to be added.

     *

     * @exception KeyManagementException if the certificate is not valid,

     * if the public key in the certificate being added conflicts with

     * this identity's public key, or if another exception occurs.

     *

     * @exception  SecurityException  if a security manager exists and its

     * {@code checkSecurityAccess} method doesn't allow

     * adding a certificate.

     *

     * @see SecurityManager#checkSecurityAccess

     */

    public void addCertificate(Certificate certificate)

    throws KeyManagementException {

        check("addIdentityCertificate");

        if (certificates == null) {

            certificates = new Vector<>();

        }

        if (publicKey != null) {

            if (!keyEquals(publicKey, certificate.getPublicKey())) {

                throw new KeyManagementException(

                    "public key different from cert public key");

            }

        } else {

            publicKey = certificate.getPublicKey();

        }

        certificates.addElement(certificate);

    }

    private boolean keyEquals(PublicKey aKey, PublicKey anotherKey) {

        String aKeyFormat = aKey.getFormat();

        String anotherKeyFormat = anotherKey.getFormat();

        if ((aKeyFormat == null) ^ (anotherKeyFormat == null))

            return false;

        if (aKeyFormat != null && anotherKeyFormat != null)

            if (!aKeyFormat.equalsIgnoreCase(anotherKeyFormat))

                return false;

        return java.util.Arrays.equals(aKey.getEncoded(),

                                     anotherKey.getEncoded());

    }

    /**

     * Removes a certificate from this identity.

     *

     * <p>First, if there is a security manager, its {@code checkSecurityAccess}

     * method is called with {@code "removeIdentityCertificate"}

     * as its argument to see if it's ok to remove a certificate.

     *

     * @param certificate the certificate to be removed.

     *

     * @exception KeyManagementException if the certificate is

     * missing, or if another exception occurs.

     *

     * @exception  SecurityException  if a security manager exists and its

     * {@code checkSecurityAccess} method doesn't allow

     * removing a certificate.

     *

     * @see SecurityManager#checkSecurityAccess

     */

    public void removeCertificate(Certificate certificate)

    throws KeyManagementException {

        check("removeIdentityCertificate");

        if (certificates != null) {

            certificates.removeElement(certificate);

        }

    }

    /**

     * Returns a copy of all the certificates for this identity.

     *

     * @return a copy of all the certificates for this identity.

     */

    public Certificate[] certificates() {

        if (certificates == null) {

            return new Certificate[0];

        }

        int len = certificates.size();

        Certificate[] certs = new Certificate[len];

        certificates.copyInto(certs);

        return certs;

    }

    /**

     * Tests for equality between the specified object and this identity.

     * This first tests to see if the entities actually refer to the same

     * object, in which case it returns true. Next, it checks to see if

     * the entities have the same name and the same scope. If they do,

     * the method returns true. Otherwise, it calls

     * {@link #identityEquals(Identity) identityEquals}, which subclasses should

     * override.

     *

     * @param identity the object to test for equality with this identity.

     *

     * @return true if the objects are considered equal, false otherwise.

     *

     * @see #identityEquals

     */

    public final boolean equals(Object identity) {

        if (identity == this) {

            return true;

        }

        if (identity instanceof Identity) {

            Identity i = (Identity)identity;

            if (this.fullName().equals(i.fullName())) {

                return true;

            } else {

                return identityEquals(i);

            }

        }

        return false;

    }

    /**

     * Tests for equality between the specified identity and this identity.

     * This method should be overriden by subclasses to test for equality.

     * The default behavior is to return true if the names and public keys

     * are equal.

     *

     * @param identity the identity to test for equality with this identity.

     *

     * @return true if the identities are considered equal, false

     * otherwise.

     *

     * @see #equals

     */

    protected boolean identityEquals(Identity identity) {

        if (!name.equalsIgnoreCase(identity.name))

            return false;

        if ((publicKey == null) ^ (identity.publicKey == null))

            return false;

        if (publicKey != null && identity.publicKey != null)

            if (!publicKey.equals(identity.publicKey))

                return false;

        return true;

    }

    /**

     * Returns a parsable name for identity: identityName.scopeName

     */

    String fullName() {

        String parsable = name;

        if (scope != null) {

            parsable += "." + scope.getName();

        }

        return parsable;

    }

    /**

     * Returns a short string describing this identity, telling its

     * name and its scope (if any).

     *

     * <p>First, if there is a security manager, its {@code checkSecurityAccess}

     * method is called with {@code "printIdentity"}

     * as its argument to see if it's ok to return the string.

     *

     * @return information about this identity, such as its name and the

     * name of its scope (if any).

     *

     * @exception  SecurityException  if a security manager exists and its

     * {@code checkSecurityAccess} method doesn't allow

     * returning a string describing this identity.

     *

     * @see SecurityManager#checkSecurityAccess

     */

    public String toString() {

        check("printIdentity");

        String printable = name;

        if (scope != null) {

            printable += "[" + scope.getName() + "]";

        }

        return printable;

    }

    /**

     * Returns a string representation of this identity, with

     * optionally more details than that provided by the

     * {@code toString} method without any arguments.

     *

     * <p>First, if there is a security manager, its {@code checkSecurityAccess}

     * method is called with {@code "printIdentity"}

     * as its argument to see if it's ok to return the string.

     *

     * @param detailed whether or not to provide detailed information.

     *

     * @return information about this identity. If {@code detailed}

     * is true, then this method returns more information than that

     * provided by the {@code toString} method without any arguments.

     *

     * @exception  SecurityException  if a security manager exists and its

     * {@code checkSecurityAccess} method doesn't allow

     * returning a string describing this identity.

     *

     * @see #toString

     * @see SecurityManager#checkSecurityAccess

     */

    public String toString(boolean detailed) {

        String out = toString();

        if (detailed) {

            out += "\n";

            out += printKeys();

            out += "\n" + printCertificates();

            if (info != null) {

                out += "\n\t" + info;

            } else {

                out += "\n\tno additional information available.";

            }

        }

        return out;

    }

    String printKeys() {

        String key = "";

        if (publicKey != null) {

            key = "\tpublic key initialized";

        } else {

            key = "\tno public key";

        }

        return key;

    }

    String printCertificates() {

        String out = "";

        if (certificates == null) {

            return "\tno certificates";

        } else {

            out += "\tcertificates: \n";

            int i = 1;

            for (Certificate cert : certificates) {

                out += "\tcertificate " + i++ +

                    "\tfor  : " + cert.getPrincipal() + "\n";

                out += "\t\t\tfrom : " +

                    cert.getGuarantor() + "\n";

            }

        }

        return out;

    }

    /**

     * Returns a hashcode for this identity.

     *

     * @return a hashcode for this identity.

     */

    public int hashCode() {

        return name.hashCode();

    }

    private static void check(String directive) {

        SecurityManager security = System.getSecurityManager();

        if (security != null) {

            security.checkSecurityAccess(directive);

        }

    }

}