/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 * 
 * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
 * 
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License. You can obtain
 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
 * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 * 
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
 * Sun designates this particular file as subject to the "Classpath" exception
 * as provided by Sun in the GPL Version 2 section of the License file that
 * accompanied this code.  If applicable, add the following below the License
 * Header, with the fields enclosed by brackets [] replaced by your own
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 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
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 */
package com.sun.enterprise.appclient;

import java.text.MessageFormat;

/**
 *Represents any user error, such as an invalid combination of command options,
 *or specifying a non-existent JAR file.
 *<p>
 *Such errors should be user-correctable, provided the message is clear.
 *So no stack traces should be displayed when UserErrors are thrown.
 *
 * @author tjquinn
 */
public class UserError extends Throwable {

    /** Allows user to turn on stack traces for user errors - normally off */
    private static final String SHOW_STACK_TRACES_PROPERTY_NAME = "com.sun.aas.appclient.showUserErrorStackTraces";
    
    /**
     * Creates a new UserError instance having formatted the message with the 
     * arguments provided.
     *@param message the message string, presumably containing argument placeholders
     *@param args 0 or more arguments for substitution for the placeholders in the message string
     *@return new UserError with message formatted as requested
     */
    public static UserError formatUserError(String message, String... args) {
        String formattedMessage = MessageFormat.format(message, (Object[]) args);
        UserError ue = new UserError(formattedMessage);
        return ue;
    }

    /** xmlMessage implementation showed the usage message after the error */
    private String usage = null;

    public UserError(String message) {
        super(message);
    }

    public UserError(String message, Throwable cause) {
        super(message, cause);
    }

    public UserError(Throwable cause) {
        super(cause);
    }

    /**
     *Sets whether or not the usage message should be displayed after the
     *error message is displayed to the user.
     *@param showUsage the new setting 
     */
    public void setUsage(String usage) {
        this.usage = usage;
    }

    /**
     *Displays the user error message, and any messages along the exception
     *chain, if any, and then exits.  If showUsage has been set to true, then
     *the usage message is displayed before exiting.
     *<p>
     *Only the messages, and not the stack traces, are shown because these are
     *user errors that should be user-correctable.  Stack traces are too
     *alarming and of minimal use to the user as he or she tries to understand
     *and fix the error.
     */
    public void displayAndExit() {
        for (Throwable t = this; t != null; t = t.getCause()) {
            System.err.println(t.getLocalizedMessage());
        }
        if (usage != null) {
            System.err.println(usage);
        }
        if (Boolean.getBoolean(SHOW_STACK_TRACES_PROPERTY_NAME)) {
            printStackTrace();
        }
        System.exit(1);
    }

}