Message.java

/* Spatial Operations & Editing Tools for uDig
 * 
 * Axios Engineering under a funding contract with: 
 * 		Diputación Foral de Gipuzkoa, Ordenación Territorial 
 *
 * 		http://b5m.gipuzkoa.net
 *      http://www.axios.es 
 *
 * (C) 2006, Diputación Foral de Gipuzkoa, Ordenación Territorial (DFG-OT). 
 * DFG-OT agrees to licence under Lesser General Public License (LGPL).
 * 
 * You can redistribute it and/or modify it under the terms of the 
 * GNU Lesser General Public License as published by the Free Software 
 * Foundation; version 2.1 of the License.
 *
 * This library 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
 * Lesser General Public License for more details.
 */
package es.axios.udig.spatialoperations.ui.view;

import org.eclipse.jface.dialogs.Dialog;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.swt.graphics.Image;

/**
 * Human Message
 * <p>
 * This class maintain the user text attributes, used by 
 * widgets to show information to user
 * </p>
 * @author Mauricio Pazos (www.axios.es)
 * @author Gabriel Roldan (www.axios.es)
 * @since 1.1.0
 */
public final class Message {
    
    
    /**
     * Type of Message
     * <p>
     * The following sentences define a criteria to use this type:
     * <ul>
     * <li>INFORMATION, IMPORTANT_INFO : Message to give an indications to user</li>
     * <li>WARNING: The value of parameter could produce a no desired result, but the operation can be executed</li> 
     * <li>ERROR: The introduced value is not valid for this operation.</li>
     * <li>FAIL The operation can not be executed correctly (typically an exceptions occurred).</li> 
     * <li>NULL: internal use</li>
     * </ul>
     * </p>
     */
    public enum Type{INFORMATION, IMPORTANT_INFO, WARNING, ERROR ,FAIL, NULL};

    public static final Message NULL = new Message("", Type.NULL); //$NON-NLS-1$


    private final String text;
    private final Type type;
    
    public Message(final String text, final Type type){
        assert text != null;
        assert type != null;

        this.text = text;
        this.type = type;
    }

    @Override
    public String toString() {
        return this.text;
    }

    @Override
    public int hashCode() {
        final int PRIME = 31;
        int result = 1;
        result = PRIME * result + ((this.text == null) ? 0 : this.text.hashCode());
        return result;
    }



    @Override
    public boolean equals( Object obj ) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        final Message other = (Message) obj;
        if (this.text == null) {
            if (other.text != null)
                return false;
        } else if (!this.text.equals(other.text))
            return false;
        if (this.type == null) {
            if (other.type != null)
                return false;
        } else if (this.type != type)
            return false;
        return true;
    }



    /**
     * @return Returns the text.
     */
    public final String getText() {
        return this.text;
    }

    /**
     * @return Returns the type.
     */
    public final Type getType() {
        return this.type;
    }
    
    /**
     * @return Returns the image
     */
    public final Image getImage(){

        Image image = null;
        
        switch( type ) {
        case FAIL:
            image = JFaceResources.getImage(Dialog.DLG_IMG_MESSAGE_ERROR);            
            break;
        case INFORMATION:
        case IMPORTANT_INFO:
            image = JFaceResources.getImage(Dialog.DLG_IMG_MESSAGE_INFO);            
            break;
        case WARNING:
            image = JFaceResources.getImage(Dialog.DLG_IMG_MESSAGE_WARNING);            
            break;
        case ERROR:
            image = JFaceResources.getImage(Dialog.DLG_IMG_MESSAGE_ERROR);            
            break;

        case NULL:
            image = null;            
            break;

        default:
            assert false; // imposible!
            break;
        }

        return image;
    }

}