InputValidator.java

/*******************************************************************************
 * Copyright (c) 2012-2017 Codenvy, S.A.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   Codenvy, S.A. - initial API and implementation
 *******************************************************************************/
package org.eclipse.che.ide.api.dialogs;

import org.eclipse.che.commons.annotation.Nullable;
import org.eclipse.che.ide.api.dialogs.InputDialog;

/**
 * Validator for {@link InputDialog}.
 *
 * @author Artem Zatsarynnyi
 */
public interface InputValidator {
    /**
     * Validates the given {@code value}.
     * <p/>
     * Returns {@link Violation} instance that may contains an error message or {@code null} if there is no validation error.
     * Note that the empty message returned by {@link Violation#getMessage()} is treated that error state but with no message to display.
     *
     * @param value
     *         value to check for validity
     * @return {@link Violation} instance if {@code value} isn't valid or {@code null} otherwise
     */
    @Nullable
    Violation validate(String value);

    /** Describes a violation of validation constraint. */
    interface Violation {
        /** Returns an error message for violation of validation constraints. */
        @Nullable
        String getMessage();

        /**
         * Returns the corrected value for replacement.
         * Note that not {@code null} value returned by this method is treated that not error state and no message to display.
         * In this case the wrong value will be replaced with the result of this method.
         */
        @Nullable
        String getCorrectedValue();
    }
}