/* IdentityScope.java --- IdentityScope Class
   Copyright (C) 1999, 2003, Free Software Foundation, Inc.

This file is part of GNU Classpath.

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package java.security;

import java.util.Enumeration;

/**
 * <code>IdentityScope</code> represents a scope of an identity.
 * <code>IdentityScope</code> is also an {@link Identity} and can have a name
 * and scope along with the other qualitites identities possess.
 * 
 * <p>An <code>IdentityScope</code> contains other {@link Identity} objects.
 * All {@link Identity} objects are manipulated in the scope the same way. The
 * scope is supposed to apply different scope to different type of
 * Identities.</p>
 * 
 * <p>No identity within the same scope can have the same public key.</p>
 * 
 * @author Mark Benvenuto
 * @see Identity
 * @see Signer
 * @see Principal
 * @see Key
 * @deprecated Use java.security.KeyStore, the java.security.cert package, and
 *             java.security.Principal.
 */
public abstract class IdentityScope extends Identity
{
  private static final long serialVersionUID = -2337346281189773310L;
  private static IdentityScope systemScope;

  /** Constructor for serialization purposes. */
  protected IdentityScope()
  {
    super();
  }

  /**
   * Constructs a new instance of <code>IdentityScope</code> with the
   * specified name and no scope.
   * 
   * @param name
   *          the name to use.
   */
  public IdentityScope(String name)
  {
    super(name);
  }

  /**
   * Constructs a new instance of <code>IdentityScope</code> with the
   * specified name and {@link IdentityScope}.
   * 
   * @param name
   *          the name to use.
   * @param scope
   *          the scope to use.
   * @throws KeyManagementException
   *           if the identity scope is already present.
   */
  public IdentityScope(String name, IdentityScope scope)
    throws KeyManagementException
  {
    super(name, scope);
  }

  /**
   * Returns the system's Scope.
   * 
   * @return the system's Scope.
   */
  public static IdentityScope getSystemScope()
  {
    if (systemScope == null)
      {
	//Load it
	//systemScope;
      }
    return systemScope;
  }

  /**
   * Sets the scope of the system.
   * 
   * @param scope
   *          the new system scope.
   * @throws SecurityException
   *           if a {@link SecurityManager} is installed which disallows this
   *           operation.
   */
  protected static void setSystemScope(IdentityScope scope)
  {
    SecurityManager sm = System.getSecurityManager();
    if (sm != null)
      sm.checkSecurityAccess("setSystemScope");

    systemScope = scope;
  }

  /**
   * Returns the number of entries within this <code>IdentityScope</code>.
   * 
   * @return the number of entries within this <code>IdentityScope</code>.
   */
  public abstract int size();

  /**
   * Returns the specified {@link Identity}, by name, within this scope.
   * 
   * @param name
   *          name of {@link Identity} to get.
   * @return an {@link Identity} representing the name or <code>null</code> if
   *         it cannot be found.
   */
  public abstract Identity getIdentity(String name);

  /**
   * Returns the specified {@link Identity}, by {@link Principal}, within this
   * scope.
   * 
   * @param principal
   *          the {@link Principal} to use.
   * @return an identity representing the {@link Principal} or <code>null</code>
   *         if it cannot be found.
   */
  public Identity getIdentity(Principal principal)
  {
    return getIdentity(principal.getName());
  }

  /**
   * Returns the specified {@link Identity}, by public key, within this scope.
   * 
   * @param key
   *          the {@link PublicKey} to use.
   * @return an identity representing the public key or <code>null</code> if
   *         it cannot be found.
   */
  public abstract Identity getIdentity(PublicKey key);

  /**
   * Adds an identity to his scope.
   * 
   * @param identity
   *          the {@link Identity} to add.
   * @throws KeyManagementException
   *           if it is an invalid identity, an identity with the same key
   *           exists, or if another error occurs.
   */
  public abstract void addIdentity(Identity identity)
    throws KeyManagementException;

  /**
   * Removes an identity in this scope.
   * 
   * @param identity
   *          the {@link Identity} to remove.
   * @throws KeyManagementException
   *           if it is a missing identity, or if another error occurs.
   */
  public abstract void removeIdentity(Identity identity)
    throws KeyManagementException;

  /**
   * Returns an {@link Enumeration} of identities in this scope.
   * 
   * @return an {@link Enumeration} of the identities in this scope.
   */
  public abstract Enumeration<Identity> identities();

  /**
   * Returns a string representing this instance. It includes the name, the
   * scope name, and number of identities.
   * 
   * @return a string representation of this instance.
   */
  public String toString()
  {
    return (super.getName() + " " + super.getScope().getName() + " " + size());
  }
}