Added test cases for EncoderStream/DecoderStream and fixed a bug

+ code clean-up to make IntelliJ happy :-)

common/common-io/src/main/java/com/twelvemonkeys/io/enc/DecoderStream.java

@@ -45,39 +45,39 @@ import java.nio.ByteBuffer;
  * @version $Id: //depot/branches/personal/haraldk/twelvemonkeys/release-2/twelvemonkeys-core/src/main/java/com/twelvemonkeys/io/enc/DecoderStream.java#2 $
  */
 public final class DecoderStream extends FilterInputStream {
-    protected final ByteBuffer buffer;
+    private final ByteBuffer buffer;
-    protected final Decoder decoder;
+    private final Decoder decoder;
 
     /**
      * Creates a new decoder stream and chains it to the
-     * input stream specified by the {@code pStream} argument.
+     * input stream specified by the {@code stream} argument.
      * The stream will use a default decode buffer size.
      *
-     * @param pStream the underlying input stream.
+     * @param stream the underlying input stream.
-     * @param pDecoder the decoder that will be used to decode the underlying stream
+     * @param decoder the decoder that will be used to decode the underlying stream
      *
      * @see java.io.FilterInputStream#in
      */
-    public DecoderStream(final InputStream pStream, final Decoder pDecoder) {
+    public DecoderStream(final InputStream stream, final Decoder decoder) {
         // TODO: Let the decoder decide preferred buffer size 
-        this(pStream, pDecoder, 1024);
+        this(stream, decoder, 1024);
     }
 
     /**
      * Creates a new decoder stream and chains it to the
-     * input stream specified by the {@code pStream} argument.
+     * input stream specified by the {@code stream} argument.
      *
-     * @param pStream the underlying input stream.
+     * @param stream the underlying input stream.
-     * @param pDecoder the decoder that will be used to decode the underlying stream
+     * @param decoder the decoder that will be used to decode the underlying stream
-     * @param pBufferSize the size of the decode buffer
+     * @param bufferSize the size of the decode buffer
      *
      * @see java.io.FilterInputStream#in
      */
-    public DecoderStream(final InputStream pStream, final Decoder pDecoder, final int pBufferSize) {
+    public DecoderStream(final InputStream stream, final Decoder decoder, final int bufferSize) {
-        super(pStream);
+        super(stream);
 
-        decoder = pDecoder;
+        this.decoder = decoder;
-        buffer = ByteBuffer.allocate(pBufferSize);
+        buffer = ByteBuffer.allocate(bufferSize);
         buffer.flip();
     }
 
@@ -95,15 +95,15 @@ public final class DecoderStream extends FilterInputStream {
         return buffer.get() & 0xff;
     }
 
-    public int read(final byte pBytes[], final int pOffset, final int pLength) throws IOException {
+    public int read(final byte[] bytes, final int offset, final int length) throws IOException {
-        if (pBytes == null) {
+        if (bytes == null) {
             throw new NullPointerException();
         }
-        else if ((pOffset < 0) || (pOffset > pBytes.length) || (pLength < 0) ||
+        else if ((offset < 0) || (offset > bytes.length) || (length < 0) ||
-                ((pOffset + pLength) > pBytes.length) || ((pOffset + pLength) < 0)) {
+                ((offset + length) > bytes.length) || ((offset + length) < 0)) {
-            throw new IndexOutOfBoundsException("bytes.length=" + pBytes.length + " offset=" + pOffset + " length=" + pLength);
+            throw new IndexOutOfBoundsException("bytes.length=" + bytes.length + " offset=" + offset + " length=" + length);
         }
-        else if (pLength == 0) {
+        else if (length == 0) {
             return 0;
         }
 
@@ -114,11 +114,11 @@ public final class DecoderStream extends FilterInputStream {
             }
         }
 
-        // Read until we have read pLength bytes, or have reached EOF
+        // Read until we have read length bytes, or have reached EOF
         int count = 0;
-        int off = pOffset;
+        int off = offset;
 
-        while (pLength > count) {
+        while (length > count) {
             if (!buffer.hasRemaining()) {
                 if (fill() < 0) {
                     break;
@@ -126,8 +126,8 @@ public final class DecoderStream extends FilterInputStream {
             }
 
             // Copy as many bytes as possible
-            int dstLen = Math.min(pLength - count, buffer.remaining());
+            int dstLen = Math.min(length - count, buffer.remaining());
-            buffer.get(pBytes, off, dstLen);
+            buffer.get(bytes, off, dstLen);
 
             // Update offset (rest)
             off += dstLen;
@@ -139,7 +139,7 @@ public final class DecoderStream extends FilterInputStream {
         return count;
     }
 
-    public long skip(final long pLength) throws IOException {
+    public long skip(final long length) throws IOException {
         // End of file?
         if (!buffer.hasRemaining()) {
             if (fill() < 0) {
@@ -147,10 +147,10 @@ public final class DecoderStream extends FilterInputStream {
             }
         }
 
-        // Skip until we have skipped pLength bytes, or have reached EOF
+        // Skip until we have skipped length bytes, or have reached EOF
         long total = 0;
 
-        while (total < pLength) {
+        while (total < length) {
             if (!buffer.hasRemaining()) {
                 if (fill() < 0) {
                     break;
@@ -158,7 +158,7 @@ public final class DecoderStream extends FilterInputStream {
             }
 
             // NOTE: Skipped can never be more than avail, which is an int, so the cast is safe
-            int skipped = (int) Math.min(pLength - total, buffer.remaining());
+            int skipped = (int) Math.min(length - total, buffer.remaining());
             buffer.position(buffer.position() + skipped);
             total += skipped;
         }
@@ -174,7 +174,7 @@ public final class DecoderStream extends FilterInputStream {
      *
      * @throws IOException if an I/O error occurs
      */
-    protected int fill() throws IOException {
+    private int fill() throws IOException {
         buffer.clear();
         int read = decoder.decode(in, buffer);
 

common/common-io/src/main/java/com/twelvemonkeys/io/enc/EncoderStream.java

@@ -45,41 +45,39 @@ import java.nio.ByteBuffer;
  * @version $Id: //depot/branches/personal/haraldk/twelvemonkeys/release-2/twelvemonkeys-core/src/main/java/com/twelvemonkeys/io/enc/EncoderStream.java#2 $
  */
 public final class EncoderStream extends FilterOutputStream {
-    // TODO: This class need a test case ASAP!!!
 
-    protected final Encoder encoder;
+    private final Encoder encoder;
     private final boolean flushOnWrite;
 
-    protected final ByteBuffer buffer;
+    private final ByteBuffer buffer;
 
     /**
      * Creates an output stream filter built on top of the specified
      * underlying output stream.
      *
-     * @param pStream the underlying output stream
+     * @param stream the underlying output stream
-     * @param pEncoder the encoder to use
+     * @param encoder the encoder to use
      */
-    public EncoderStream(final OutputStream pStream, final Encoder pEncoder) {
+    public EncoderStream(final OutputStream stream, final Encoder encoder) {
-        this(pStream, pEncoder, false);
+        this(stream, encoder, false);
     }
 
     /**
      * Creates an output stream filter built on top of the specified
      * underlying output stream.
      *
-     * @param pStream the underlying output stream
+     * @param stream the underlying output stream
-     * @param pEncoder the encoder to use
+     * @param encoder the encoder to use
-     * @param pFlushOnWrite if {@code true}, calls to the byte-array
+     * @param flushOnWrite if {@code true}, calls to the byte-array
      * {@code write} methods will automatically flush the buffer.
      */
-    public EncoderStream(final OutputStream pStream, final Encoder pEncoder, final boolean pFlushOnWrite) {
+    public EncoderStream(final OutputStream stream, final Encoder encoder, final boolean flushOnWrite) {
-        super(pStream);
+        super(stream);
 
-        encoder = pEncoder;
+        this.encoder = encoder;
-        flushOnWrite = pFlushOnWrite;
+        this.flushOnWrite = flushOnWrite;
 
         buffer = ByteBuffer.allocate(1024);
-        buffer.flip();
     }
 
     public void close() throws IOException {
@@ -104,33 +102,33 @@ public final class EncoderStream extends FilterOutputStream {
         }
     }
 
-    public final void write(final byte[] pBytes) throws IOException {
+    public void write(final byte[] bytes) throws IOException {
-        write(pBytes, 0, pBytes.length);
+        write(bytes, 0, bytes.length);
     }
 
     // TODO: Verify that this works for the general case (it probably won't)...
     // TODO: We might need a way to explicitly flush the encoder, or specify
     // that the encoder can't buffer. In that case, the encoder should probably
-    // tell the EncoderStream how large buffer it prefers... 
+    // tell the EncoderStream how large buffer it prefers...
-    public void write(final byte[] pBytes, final int pOffset, final int pLength) throws IOException {
+    public void write(final byte[] values, final int offset, final int length) throws IOException {
-        if (!flushOnWrite && pLength < buffer.remaining()) {
+        if (!flushOnWrite && length < buffer.remaining()) {
             // Buffer data
-            buffer.put(pBytes, pOffset, pLength);
+            buffer.put(values, offset, length);
         }
         else {
             // Encode data already in the buffer
             encodeBuffer();
 
             // Encode rest without buffering
-            encoder.encode(out, ByteBuffer.wrap(pBytes, pOffset, pLength));
+            encoder.encode(out, ByteBuffer.wrap(values, offset, length));
         }
     }
 
-    public void write(final int pByte) throws IOException {
+    public void write(final int value) throws IOException {
         if (!buffer.hasRemaining()) {
             encodeBuffer(); // Resets bufferPos to 0
         }
 
-        buffer.put((byte) pByte);
+        buffer.put((byte) value);
     }
 }

common/common-io/src/test/java/com/twelvemonkeys/io/enc/DecoderStreamTest.java

@@ -0,0 +1,130 @@
+/*
+ * Copyright (c) 2022, Harald Kuhr
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ * * 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.
+ *
+ * * Neither the name of the copyright holder nor the names of its
+ *   contributors may be used to endorse or promote products derived from
+ *   this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.
+ */
+
+package com.twelvemonkeys.io.enc;
+
+import org.junit.Test;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.util.Arrays;
+import java.util.Random;
+
+import static org.junit.Assert.*;
+
+public class DecoderStreamTest {
+
+    private final Random rng = new Random(5467809876546L);
+
+    private byte[] createData(final int length) {
+        byte[] data = new byte[length];
+        rng.nextBytes(data);
+        return data;
+    }
+
+    @Test
+    public void testDecodeSingleBytes() throws IOException {
+        byte[] data = createData(1327);
+
+        InputStream source = new ByteArrayInputStream(data);
+        try (InputStream stream = new DecoderStream(source, new NullDecoder())) {
+            for (byte datum : data) {
+                int read = stream.read();
+                assertNotEquals(-1, read);
+                assertEquals(datum, (byte) read);
+            }
+
+            assertEquals(-1, stream.read());
+        }
+    }
+
+    @Test
+    public void testDecodeArray() throws IOException {
+        int length = 793;
+        byte[] data = createData(length * 10);
+
+        InputStream source = new ByteArrayInputStream(data);
+        byte[] result = new byte[477];
+
+        try (InputStream stream = new DecoderStream(source, new NullDecoder())) {
+            int dataOffset = 0;
+            while (dataOffset < data.length) {
+                int count = stream.read(result);
+
+                assertFalse(count <= 0);
+                assertArrayEquals(Arrays.copyOfRange(data, dataOffset, dataOffset + count), Arrays.copyOfRange(result, 0, count));
+
+                dataOffset += count;
+            }
+
+            assertEquals(-1, stream.read());
+        }
+    }
+
+    @Test
+    public void testDecodeArrayOffset() throws IOException {
+        int length = 793;
+        byte[] data = createData(length * 10);
+
+        InputStream source = new ByteArrayInputStream(data);
+        byte[] result = new byte[477];
+
+        try (InputStream stream = new DecoderStream(source, new NullDecoder())) {
+            int dataOffset = 0;
+            while (dataOffset < data.length) {
+                int resultOffset = dataOffset % result.length;
+                int count = stream.read(result, resultOffset, result.length - resultOffset);
+
+                assertFalse(count <= 0);
+                assertArrayEquals(Arrays.copyOfRange(data, dataOffset + resultOffset, dataOffset + count), Arrays.copyOfRange(result, resultOffset, count));
+
+                dataOffset += count;
+            }
+
+            assertEquals(-1, stream.read());
+        }
+    }
+
+    private static final class NullDecoder implements Decoder {
+        @Override
+        public int decode(InputStream stream, ByteBuffer buffer) throws IOException {
+            int read = stream.read(buffer.array(), buffer.arrayOffset(), buffer.remaining());
+
+            if (read > 0) {
+                // Set position, should be equivalent to using buffer.put(stream.read()) until EOF or buffer full
+                buffer.position(read);
+            }
+
+            return read;
+        }
+    }
+}

common/common-io/src/test/java/com/twelvemonkeys/io/enc/EncoderStreamTest.java

@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2022, Harald Kuhr
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ * * 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.
+ *
+ * * Neither the name of the copyright holder nor the names of its
+ *   contributors may be used to endorse or promote products derived from
+ *   this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.
+ */
+
+package com.twelvemonkeys.io.enc;
+
+import org.junit.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.nio.ByteBuffer;
+import java.util.Arrays;
+import java.util.Random;
+
+import static org.junit.Assert.assertArrayEquals;
+
+public class EncoderStreamTest {
+
+    private final Random rng = new Random(5467809876546L);
+
+    private byte[] createData(final int length) {
+        byte[] data = new byte[length];
+        rng.nextBytes(data);
+        return data;
+    }
+
+    @Test
+    public void testEncodeSingleBytes() throws IOException {
+        byte[] data = createData(1327);
+
+        ByteArrayOutputStream result = new ByteArrayOutputStream();
+        try (OutputStream stream = new EncoderStream(result, new NullEncoder())) {
+            for (byte datum : data) {
+                stream.write(datum);
+            }
+        }
+
+        assertArrayEquals(data, result.toByteArray());
+    }
+
+    @Test
+    public void testEncodeArray() throws IOException {
+        byte[] data = createData(1793);
+
+        ByteArrayOutputStream result = new ByteArrayOutputStream();
+        try (OutputStream stream = new EncoderStream(result, new NullEncoder())) {
+            for (int i = 0; i < 10; i++) {
+                stream.write(data);
+            }
+        }
+
+        byte[] encoded = result.toByteArray();
+
+        for (int i = 0; i < 10; i++) {
+            assertArrayEquals(data, Arrays.copyOfRange(encoded, i * data.length, (i + 1) * data.length));
+        }
+    }
+
+    @Test
+    public void testEncodeArrayOffset() throws IOException {
+        byte[] data = createData(87);
+
+        ByteArrayOutputStream result = new ByteArrayOutputStream();
+        try (OutputStream stream = new EncoderStream(result, new NullEncoder())) {
+            for (int i = 0; i < 10; i++) {
+                stream.write(data, 13, 59);
+            }
+        }
+
+        byte[] original = Arrays.copyOfRange(data, 13, 13 + 59);
+        byte[] encoded = result.toByteArray();
+
+        for (int i = 0; i < 10; i++) {
+            assertArrayEquals(original, Arrays.copyOfRange(encoded, i * original.length, (i + 1) * original.length));
+        }
+    }
+
+    private static final class NullEncoder implements Encoder {
+        @Override
+        public void encode(OutputStream stream, ByteBuffer buffer) throws IOException {
+            stream.write(buffer.array(), buffer.arrayOffset(), buffer.remaining());
+        }
+    }
+}