Replace strings within a Java InputStream without pulling all of the data first

ReplacingInputStream.java

package io.divby0.utils;

import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.Queue;

/**
 * Created by simon on 8/29/17.
 * Copyright 2017 Simon Haoran Liang
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
 * associated documentation files (the "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the
 * following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or substantial
 * portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
 * LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
 * NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
public class ReplacingInputStream extends FilterInputStream {

    private Queue<Integer> inQueue, outQueue;
    private final byte[] search, replacement;

    public ReplacingInputStream(InputStream in, String search, String replacement) {
        super(in);

        this.inQueue = new LinkedList<>();
        this.outQueue = new LinkedList<>();

        this.search = search.getBytes();
        this.replacement = replacement.getBytes();
    }

    private boolean isMatchFound() {
        Iterator<Integer> iterator = inQueue.iterator();

        for (byte b : search) {
            if (!iterator.hasNext() || b != iterator.next()) {
                return false;
            }
        }

        return true;
    }

    private void readAhead() throws IOException {
        // Work up some look-ahead.
        while (inQueue.size() < search.length) {
            int next = super.read();
            inQueue.offer(next);

            if (next == -1) {
                break;
            }
        }
    }

    @Override
    public int read() throws IOException {
        // Next byte already determined.

        while (outQueue.isEmpty()) {
            readAhead();

            if (isMatchFound()) {
                for (byte a : search) {
                    inQueue.remove();
                }

                for (byte b : replacement) {
                    outQueue.offer((int) b);
                }
            } else {
                outQueue.add(inQueue.remove());
            }
        }

        return outQueue.remove();
    }

    @Override
    public int read(byte b[]) throws IOException {
        return read(b, 0, b.length);
    }

    // copied straight from InputStream inplementation, just needed to to use `read()` from this class
    @Override
    public int read(byte b[], int off, int len) throws IOException {
        if (b == null) {
            throw new NullPointerException();
        } else if (off < 0 || len < 0 || len > b.length - off) {
            throw new IndexOutOfBoundsException();
        } else if (len == 0) {
            return 0;
        }

        int c = read();
        if (c == -1) {
            return -1;
        }
        b[off] = (byte)c;

        int i = 1;
        try {
            for (; i < len ; i++) {
                c = read();
                if (c == -1) {
                    break;
                }
                b[off + i] = (byte)c;
            }
        } catch (IOException ee) {
        }
        return i;
    }
}

ReplacingInputStreamTest.java

package io.divby0.utils;

import org.junit.Before;
import org.junit.Test;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;

import static org.junit.Assert.*;

/**
 * Created by simon on 8/29/17.
 * Copyright 2017 Simon Haoran Liang
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
 * associated documentation files (the "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the
 * following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or substantial
 * portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
 * LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
 * NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
public class ReplacingInputStreamTest {

    private byte[] bytes;
    private ByteArrayInputStream bis;
    private ReplacingInputStream ris;
    private ByteArrayOutputStream bos;

    @Before
    public void beforeTest() throws Exception {
        bytes = "hello xyz world.".getBytes("UTF-8");
        bis = new ByteArrayInputStream(bytes);
    }

    @Test
    public void testReplacingInputStream() throws Exception {
        ris = new ReplacingInputStream(bis, "xyz", "abc");
        bos = new ByteArrayOutputStream();

        int b;
        while (-1 != (b = ris.read()))
            bos.write(b);

        assertEquals("hello abc world.", bos.toString());
    }

    @Test
    public void testReplacingToEmptyString() throws Exception {
        ris = new ReplacingInputStream(bis, "xyz", "");
        bos = new ByteArrayOutputStream();

        int b;
        while (-1 != (b = ris.read()))
            bos.write(b);

        assertEquals("hello  world.", bos.toString());
    }
}

Under what licence is your code? Could you add a licence to your repo?
It would be nice if it would be AGPLv3 as the project where I like to use your code uses AGPLv3.

Under what licence is your code? Could you add a licence to your repo?
It would be nice if it would be AGPLv3 as the project where I like to use your code uses AGPLv3.

@INOPIAE Hey I have added MIT License to the above code snippets, please let me know if that's good for your use case.

Using the MIT license works well in conjunction with the project that this class should be used in as it is compatible with AGPLv3 that is used in said project.