    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017package org.apache.commons.io.input;
    018
    019import java.io.IOException;
    020import java.io.InputStream;
    021
    022/**
    023 * This is an alternative to {@link java.io.ByteArrayInputStream}
    024 * which removes the synchronization overhead for non-concurrent
    025 * access; as such this class is not thread-safe.
    026 *
    027 * Proxy stream that prevents the underlying input stream from being marked/reset.
    028 * <p>
    029 * This class is typically used in cases where an input stream that supports
    030 * marking needs to be passed to a component that wants to explicitly mark
    031 * the stream, but it it is not desirable to allow marking of the stream.
    032 * </p>
    033 *
    034 * @since 2.8.0
    035 */
    036public class MarkShieldInputStream extends ProxyInputStream {
    037
    038    /**
    039     * Creates a proxy that shields the given input stream from being
    040     * marked or rest.
    041     *
    042     * @param in underlying input stream
    043     */
    044    public MarkShieldInputStream(final InputStream in) {
    045        super(in);
    046    }
    047
    048    @SuppressWarnings("sync-override")
    049    @Override
    050    public void mark(final int readlimit) {
    051        // no-op
    052    }
    053
    054    @Override
    055    public boolean markSupported() {
    056        return false;
    057    }
    058
    059    @SuppressWarnings("sync-override")
    060    @Override
    061    public void reset() throws IOException {
    062        throw UnsupportedOperationExceptions.reset();
    063    }
    064}