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 * Copyright (c) 1999, 2015, 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

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 */

package javax.security.auth.callback;

/**

 * <p> Underlying security services instantiate and pass a

 * {@code ChoiceCallback} to the {@code handle}

 * method of a {@code CallbackHandler} to display a list of choices

 * and to retrieve the selected choice(s).

 *

 * @since 1.4

 * @see javax.security.auth.callback.CallbackHandler

 */

public class ChoiceCallback implements Callback, java.io.Serializable {

    private static final long serialVersionUID = -3975664071579892167L;

    /**

     * @serial

     * @since 1.4

     */

    private String prompt;

    /**

     * @serial the list of choices

     * @since 1.4

     */

    private String[] choices;

    /**

     * @serial the choice to be used as the default choice

     * @since 1.4

     */

    private int defaultChoice;

    /**

     * @serial whether multiple selections are allowed from the list of

     * choices

     * @since 1.4

     */

    private boolean multipleSelectionsAllowed;

    /**

     * @serial the selected choices, represented as indexes into the

     *          {@code choices} list.

     * @since 1.4

     */

    private int[] selections;

    /**

     * Construct a {@code ChoiceCallback} with a prompt,

     * a list of choices, a default choice, and a boolean specifying

     * whether or not multiple selections from the list of choices are allowed.

     *

     *

     * @param prompt the prompt used to describe the list of choices.

     *

     * @param choices the list of choices.

     *

     * @param defaultChoice the choice to be used as the default choice

     *                  when the list of choices are displayed.  This value

     *                  is represented as an index into the

     *                  {@code choices} array.

     *

     * @param multipleSelectionsAllowed boolean specifying whether or

     *                  not multiple selections can be made from the

     *                  list of choices.

     *

     * @exception IllegalArgumentException if {@code prompt} is null,

     *                  if {@code prompt} has a length of 0,

     *                  if {@code choices} is null,

     *                  if {@code choices} has a length of 0,

     *                  if any element from {@code choices} is null,

     *                  if any element from {@code choices}

     *                  has a length of 0 or if {@code defaultChoice}

     *                  does not fall within the array boundaries of

     *                  {@code choices}.

     */

    public ChoiceCallback(String prompt, String[] choices,

                int defaultChoice, boolean multipleSelectionsAllowed) {

            choices == null || choices.length == 0 ||

            defaultChoice < 0 || defaultChoice >= choices.length)

            throw new IllegalArgumentException();

        for (int i = 0; i < choices.length; i++) {

                throw new IllegalArgumentException();

        }

        this.prompt = prompt;

        this.choices = choices;

        this.defaultChoice = defaultChoice;

        this.multipleSelectionsAllowed = multipleSelectionsAllowed;

    }

    /**

     * Get the prompt.

     *

     * @return the prompt.

     */

    public String getPrompt() {

        return prompt;

    }

    /**

     * Get the list of choices.

     *

     * @return the list of choices.

     */

    public String[] getChoices() {

        return choices;

    }

    /**

     * Get the defaultChoice.

     *

     * @return the defaultChoice, represented as an index into

     *          the {@code choices} list.

     */

    public int getDefaultChoice() {

        return defaultChoice;

    }

    /**

     * Get the boolean determining whether multiple selections from

     * the {@code choices} list are allowed.

     *

     * @return whether multiple selections are allowed.

     */

    public boolean allowMultipleSelections() {

        return multipleSelectionsAllowed;

    }

    /**

     * Set the selected choice.

     *

     * @param selection the selection represented as an index into the

     *          {@code choices} list.

     *

     * @see #getSelectedIndexes

     */

    public void setSelectedIndex(int selection) {

        this.selections = new int[1];

        this.selections[0] = selection;

    }

    /**

     * Set the selected choices.

     *

     * @param selections the selections represented as indexes into the

     *          {@code choices} list.

     *

     * @exception UnsupportedOperationException if multiple selections are

     *          not allowed, as determined by

     *          {@code allowMultipleSelections}.

     *

     * @see #getSelectedIndexes

     */

    public void setSelectedIndexes(int[] selections) {

        if (!multipleSelectionsAllowed)

            throw new UnsupportedOperationException();

        this.selections = selections;

    }

    /**

     * Get the selected choices.

     *

     * @return the selected choices, represented as indexes into the

     *          {@code choices} list.

     *

     * @see #setSelectedIndexes

     */

    public int[] getSelectedIndexes() {

        return selections;

    }

}