# FileUploadException.java

    /*
     * Licensed to the Apache Software Foundation (ASF) under one or more
     * contributor license agreements.  See the NOTICE file distributed with
     * this work for additional information regarding copyright ownership.
     * The ASF licenses this file to You under the Apache License, Version 2.0
     * (the "License"); you may not use this file except in compliance with
     * the License.  You may obtain a copy of the License at
     *
     *      http://www.apache.org/licenses/LICENSE-2.0
     *
     * Unless required by applicable law or agreed to in writing, software
     * distributed under the License is distributed on an "AS IS" BASIS,
     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     * See the License for the specific language governing permissions and
     * limitations under the License.
     */
    package org.apache.commons.fileupload;

    import java.io.PrintStream;
    import java.io.PrintWriter;

    /**
     * Exception for errors encountered while processing the request.
     */
    public class FileUploadException extends Exception {

        /**
         * Serial version UID, being used, if the exception
         * is serialized.
         */
        private static final long serialVersionUID = 8881893724388807504L;

        /**
         * The exceptions cause. We overwrite the cause of
         * the super class, which isn't available in Java 1.3.
         */
        private final Throwable cause;

        /**
         * Constructs a new <code>FileUploadException</code> without message.
         */
        public FileUploadException() {
            this(null, null);
        }

        /**
         * Constructs a new <code>FileUploadException</code> with specified detail
         * message.
         *
         * @param msg the error message.
         */
        public FileUploadException(final String msg) {
            this(msg, null);
        }

        /**
         * Creates a new <code>FileUploadException</code> with the given
         * detail message and cause.
         *
         * @param msg The exceptions detail message.
         * @param cause The exceptions cause.
         */
        public FileUploadException(String msg, Throwable cause) {
            super(msg);
            this.cause = cause;
        }

        /**
         * Prints this throwable and its backtrace to the specified print stream.
         *
         * @param stream <code>PrintStream</code> to use for output
         */
        @Override
        public void printStackTrace(PrintStream stream) {
            super.printStackTrace(stream);
            if (cause != null) {
                stream.println("Caused by:");
                cause.printStackTrace(stream);
            }
        }

        /**
         * Prints this throwable and its backtrace to the specified
         * print writer.
         *
         * @param writer <code>PrintWriter</code> to use for output
         */
        @Override
        public void printStackTrace(PrintWriter writer) {
            super.printStackTrace(writer);
            if (cause != null) {
                writer.println("Caused by:");
                cause.printStackTrace(writer);
            }
        }

        /**
         * {@inheritDoc}
         */
        @Override
        public Throwable getCause() {
            return cause;
        }

    }