/*******************************************************************************
 * Copyright (c) 2000, 2004 IBM Corporation and others.
 * 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jface.dialogs;

/**
 * Minimal interface to a message provider. Used for dialog pages which can
 * provide a message with an icon.
 * 
 * @since 2.0
 */
public interface IMessageProvider {
    /**
     * Constant for a regular message (value 0).
     * <p>
     * Typically this indicates that the message should be shown without an
     * icon.
     * </p>
     */
    public final static int NONE = 0;

    /**
     * Constant for an info message (value 1).
     */
    public final static int INFORMATION = 1;

    /**
     * Constant for a warning message (value 2).
     */
    public final static int WARNING = 2;

    /**
     * Constant for an error message (value 3).
     */
    public final static int ERROR = 3;

    /**
     * Returns the current message for this message provider.
     * <p>
     * A message provides instruction or information to the user.
     * </p>
     * 
     * @return the message, or <code>null</code> if none
     */
    public String getMessage();

    /**
     * Returns a value indicating if the message is a an information message, a
     * warning message, or an error message.
     * <p>
     * Returns one of <code>NONE</code>,<code>INFORMATION</code>,
     * <code>WARNING</code>, or <code>ERROR</code>.
     * </p>
     * 
     * @return the message type
     */
    public int getMessageType();
}