/*
 * Copyright (c) 2017, 2018 Oracle and/or its affiliates and others.
 * All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package javax.servlet;

import javax.servlet.annotation.HttpConstraint;
import javax.servlet.annotation.ServletSecurity.EmptyRoleSemantic;
import javax.servlet.annotation.ServletSecurity.TransportGuarantee;

Java Class representation of an HttpConstraint annotation value. 
Since:
Servlet 3.0/**
 * Java Class representation of an {@link HttpConstraint} annotation value.
 *
 * @since Servlet 3.0
 */
public class HttpConstraintElement {

    private EmptyRoleSemantic emptyRoleSemantic;
    private TransportGuarantee transportGuarantee;
    private String[] rolesAllowed;

    
Constructs a default HTTP constraint element
/**
     * Constructs a default HTTP constraint element
     */
    public HttpConstraintElement() {
        this(EmptyRoleSemantic.PERMIT);
    }

    
Convenience constructor to establish EmptyRoleSemantic.DENY
Params:
semantic – should be EmptyRoleSemantic.DENY/**
     * Convenience constructor to establish <tt>EmptyRoleSemantic.DENY</tt>
     *
     * @param semantic should be EmptyRoleSemantic.DENY
     */
    public HttpConstraintElement(EmptyRoleSemantic semantic) {
        this(semantic, TransportGuarantee.NONE, new String[0]);
    }

    
Constructor to establish non-empty getRolesAllowed and/or TransportGuarantee.CONFIDENTIAL.
Params:
guarantee – TransportGuarantee.NONE or TransportGuarantee.CONFIDENTIAL
roleNames – the names of the roles that are to be allowed access/**
     * Constructor to establish non-empty getRolesAllowed and/or <tt>TransportGuarantee.CONFIDENTIAL</tt>.
     *
     * @param guarantee <tt>TransportGuarantee.NONE</tt> or <tt>TransportGuarantee.CONFIDENTIAL</tt>
     * @param roleNames the names of the roles that are to be allowed access
     */
    public HttpConstraintElement(TransportGuarantee guarantee, String... roleNames) {
        this(EmptyRoleSemantic.PERMIT, guarantee, roleNames);
    }

    
Constructor to establish all of getEmptyRoleSemantic, getRolesAllowed, and getTransportGuarantee.
Params:
semantic –  EmptyRoleSemantic.DENY or EmptyRoleSemantic.PERMIT
guarantee – TransportGuarantee.NONE or TransportGuarantee.CONFIDENTIAL
roleNames – the names of the roles that are to be allowed access, or missing if the semantic is
                 EmptyRoleSemantic.DENY/**
     * Constructor to establish all of getEmptyRoleSemantic, getRolesAllowed, and getTransportGuarantee.
     *
     * @param semantic  <tt>EmptyRoleSemantic.DENY</tt> or <tt>EmptyRoleSemantic.PERMIT</tt>
     * @param guarantee <tt>TransportGuarantee.NONE</tt> or <tt>TransportGuarantee.CONFIDENTIAL</tt>
     * @param roleNames the names of the roles that are to be allowed access, or missing if the semantic is
     *                  <tt>EmptyRoleSemantic.DENY</tt>
     */
    public HttpConstraintElement(EmptyRoleSemantic semantic, TransportGuarantee guarantee, String... roleNames) {
        if (semantic == EmptyRoleSemantic.DENY && roleNames.length > 0) {
            throw new IllegalArgumentException("Deny semantic with rolesAllowed");
        }
        this.emptyRoleSemantic = semantic;
        this.transportGuarantee = guarantee;
        this.rolesAllowed = copyStrings(roleNames);
    }

    
Gets the default authorization semantic.

This value is insignificant when getRolesAllowed returns a non-empty array, and should not be
specified when a non-empty array is specified for getRolesAllowed.
Returns:
the EmptyRoleSemantic to be applied when getRolesAllowed returns an empty (that is,
        zero-length) array/**
     * Gets the default authorization semantic.
     *
     * <p>
     * This value is insignificant when <code>getRolesAllowed</code> returns a non-empty array, and should not be
     * specified when a non-empty array is specified for <tt>getRolesAllowed</tt>.
     *
     * @return the {@link EmptyRoleSemantic} to be applied when <code>getRolesAllowed</code> returns an empty (that is,
     *         zero-length) array
     */
    public EmptyRoleSemantic getEmptyRoleSemantic() {
        return this.emptyRoleSemantic;
    }

    
Gets the data protection requirement (i.e., whether or not SSL/TLS is required) that must be satisfied by the
transport connection.
Returns:
the TransportGuarantee indicating the data protection that must be provided by the connection/**
     * Gets the data protection requirement (i.e., whether or not SSL/TLS is required) that must be satisfied by the
     * transport connection.
     *
     * @return the {@link TransportGuarantee} indicating the data protection that must be provided by the connection
     */
    public TransportGuarantee getTransportGuarantee() {
        return this.transportGuarantee;
    }

    
Gets the names of the authorized roles.

Duplicate role names appearing in getRolesAllowed are insignificant and may be discarded. The String "*"
has no special meaning as a role name (should it occur in getRolesAllowed).
Returns:
a (possibly empty) array of role names. When the array is empty, its meaning depends on the value of getEmptyRoleSemantic. If its value is DENY, and getRolesAllowed returns an
        empty array, access is to be denied independent of authentication state and identity. Conversely, if its
        value is PERMIT, it indicates that access is to be allowed independent of authentication state and identity. When the array contains the names of one or more roles, it indicates that access is contingent on membership in at least one of the named roles (independent of the value of getEmptyRoleSemantic)./**
     * Gets the names of the authorized roles.
     *
     * <p>
     * Duplicate role names appearing in getRolesAllowed are insignificant and may be discarded. The String <tt>"*"</tt>
     * has no special meaning as a role name (should it occur in getRolesAllowed).
     *
     * @return a (possibly empty) array of role names. When the array is empty, its meaning depends on the value of
     *         {@link #getEmptyRoleSemantic}. If its value is <tt>DENY</tt>, and <code>getRolesAllowed</code> returns an
     *         empty array, access is to be denied independent of authentication state and identity. Conversely, if its
     *         value is <code>PERMIT</code>, it indicates that access is to be allowed independent of authentication
     *         state and identity. When the array contains the names of one or more roles, it indicates that access is
     *         contingent on membership in at least one of the named roles (independent of the value of
     *         {@link #getEmptyRoleSemantic}).
     */
    public String[] getRolesAllowed() {
        return copyStrings(this.rolesAllowed);
    }

    private String[] copyStrings(String[] strings) {
        String[] arr = null;
        if (strings != null) {
            int len = strings.length;
            arr = new String[len];
            if (len > 0) {
                System.arraycopy(strings, 0, arr, 0, len);
            }
        }

        return ((arr != null) ? arr : new String[0]);
    }
}