NonCloseableInputStream.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.nifi.stream.io;

import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;

/**
 * Wraps and InputStream so that the underlying InputStream cannot be closed. This is used so that the InputStream can be wrapped with yet another InputStream and prevent the outer layer from closing
 * the inner InputStream
 */
public class NonCloseableInputStream extends FilterInputStream {

    private final InputStream toWrap;

    public NonCloseableInputStream(final InputStream toWrap) {
        super(toWrap);
        this.toWrap = toWrap;
    }

    @Override
    public int read() throws IOException {
        return toWrap.read();
    }

    @Override
    public int read(byte[] b) throws IOException {
        return toWrap.read(b);
    }

    @Override
    public int read(byte[] b, int off, int len) throws IOException {
        return toWrap.read(b, off, len);
    }

    @Override
    public void close() throws IOException {
        // do nothing
    }
}