unavailableexception.java

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// UnavailableException - an exception for Servlets
//
// Copyright (C) 1996,1998 by Jef Poskanzer <[e-mail]>. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 1. Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright
//    notice, this list of conditions and the following disclaimer in the
//    documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
// OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
// SUCH DAMAGE.
//
// Visit the ACME Labs Java page for up-to-date versions of this and other
// fine Java utilities: http://www.acme.com/java/

package Acme.Serve.servlet;

import java.io.*;

/// An exception for Servlets.
// <P>
// <A HREF="/resources/classes/Acme/Serve/servlet/UnavailableException.java">Fetch the software.</A><BR>
// <A HREF="/resources/classes/Acme.tar.gz">Fetch the entire Acme package.</A>

public class UnavailableException extends ServletException
    {

    private boolean permanent;
    private int seconds;
    private Servlet servlet;

    /// Constructs an UnavailableException with the specified detail message,
    // indicating the servlet is permanently unavailable.
    public UnavailableException( Servlet servlet, String msg )
	{
	super( msg );
	permanent = true;
	this.servlet = servlet;
	}

    /// Constructs an UnavailableException with the specified detail message,
    // indicating that the servlet is temporarily unavailable and giving an
    // estimate of how long it will be unavailable. In some cases, no
    // estimate can be made; this is indicated by a non-positive time. 
    public UnavailableException( int seconds, Servlet servlet, String msg )
	{
	super( msg );
	permanent = false;
	this.seconds = seconds;
	this.servlet = servlet;
	}

    /// Returns true if the servlet is "permanently" unavailable, indicating
    // that the service administrator must take some corrective action to
    // make the servlet be usable.
    public boolean isPermanent()
	{
	return permanent;
	}

    /// Returns the servlet that is reporting its unavailability.
    public Servlet getServlet()
	{
	return servlet;
	}

    /// Returns the amount of time the servlet expects to be temporarily
    // unavailable.
    public int getUnavailableSeconds()
	{
	return seconds;
	}

    }