1 files changed, 619 insertions, 0 deletions
diff --git a/third_party/protobuf/3.6.0/java/core/src/test/java/com/google/protobuf/NioByteStringTest.java b/third_party/protobuf/3.6.0/java/core/src/test/java/com/google/protobuf/NioByteStringTest.java
new file mode 100644
index 0000000000..c388bd0561
--- /dev/null
+++ b/third_party/protobuf/3.6.0/java/core/src/test/java/com/google/protobuf/NioByteStringTest.java
@@ -0,0 +1,619 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// 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 Google Inc. 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
+// OWNER 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.google.protobuf;
+
+import static com.google.protobuf.Internal.UTF_8;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.EOFException;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.OutputStream;
+import java.io.UnsupportedEncodingException;
+import java.nio.BufferOverflowException;
+import java.nio.ByteBuffer;
+import java.util.Arrays;
+import java.util.List;
+import java.util.NoSuchElementException;
+import junit.framework.TestCase;
+
+/**
+ * Tests for {@link NioByteString}.
+ */
+public class NioByteStringTest extends TestCase {
+  private static final ByteString EMPTY = new NioByteString(ByteBuffer.wrap(new byte[0]));
+  private static final String CLASSNAME = NioByteString.class.getSimpleName();
+  private static final byte[] BYTES = ByteStringTest.getTestBytes(1234, 11337766L);
+  private static final int EXPECTED_HASH = ByteString.wrap(BYTES).hashCode();
+
+  private final ByteBuffer backingBuffer = ByteBuffer.wrap(BYTES.clone());
+  private final ByteString testString = new NioByteString(backingBuffer);
+
+  public void testExpectedType() {
+    String actualClassName = getActualClassName(testString);
+    assertEquals(CLASSNAME + " should match type exactly", CLASSNAME, actualClassName);
+  }
+
+  protected String getActualClassName(Object object) {
+    String actualClassName = object.getClass().getName();
+    actualClassName = actualClassName.substring(actualClassName.lastIndexOf('.') + 1);
+    return actualClassName;
+  }
+
+  public void testByteAt() {
+    boolean stillEqual = true;
+    for (int i = 0; stillEqual && i < BYTES.length; ++i) {
+      stillEqual = (BYTES[i] == testString.byteAt(i));
+    }
+    assertTrue(CLASSNAME + " must capture the right bytes", stillEqual);
+  }
+
+  public void testByteIterator() {
+    boolean stillEqual = true;
+    ByteString.ByteIterator iter = testString.iterator();
+    for (int i = 0; stillEqual && i < BYTES.length; ++i) {
+      stillEqual = (iter.hasNext() && BYTES[i] == iter.nextByte());
+    }
+    assertTrue(CLASSNAME + " must capture the right bytes", stillEqual);
+    assertFalse(CLASSNAME + " must have exhausted the itertor", iter.hasNext());
+
+    try {
+      iter.nextByte();
+      fail("Should have thrown an exception.");
+    } catch (NoSuchElementException e) {
+      // This is success
+    }
+  }
+
+  public void testByteIterable() {
+    boolean stillEqual = true;
+    int j = 0;
+    for (byte quantum : testString) {
+      stillEqual = (BYTES[j] == quantum);
+      ++j;
+    }
+    assertTrue(CLASSNAME + " must capture the right bytes as Bytes", stillEqual);
+    assertEquals(CLASSNAME + " iterable character count", BYTES.length, j);
+  }
+
+  public void testSize() {
+    assertEquals(CLASSNAME + " must have the expected size", BYTES.length,
+        testString.size());
+  }
+
+  public void testGetTreeDepth() {
+    assertEquals(CLASSNAME + " must have depth 0", 0, testString.getTreeDepth());
+  }
+
+  public void testIsBalanced() {
+    assertTrue(CLASSNAME + " is technically balanced", testString.isBalanced());
+  }
+
+  public void testCopyTo_ByteArrayOffsetLength() {
+    int destinationOffset = 50;
+    int length = 100;
+    byte[] destination = new byte[destinationOffset + length];
+    int sourceOffset = 213;
+    testString.copyTo(destination, sourceOffset, destinationOffset, length);
+    boolean stillEqual = true;
+    for (int i = 0; stillEqual && i < length; ++i) {
+      stillEqual = BYTES[i + sourceOffset] == destination[i + destinationOffset];
+    }
+    assertTrue(CLASSNAME + ".copyTo(4 arg) must give the expected bytes", stillEqual);
+  }
+
+  public void testCopyTo_ByteArrayOffsetLengthErrors() {
+    int destinationOffset = 50;
+    int length = 100;
+    byte[] destination = new byte[destinationOffset + length];
+
+    try {
+      // Copy one too many bytes
+      testString.copyTo(destination, testString.size() + 1 - length,
+          destinationOffset, length);
+      fail("Should have thrown an exception when copying too many bytes of a "
+          + CLASSNAME);
+    } catch (IndexOutOfBoundsException expected) {
+      // This is success
+    }
+
+    try {
+      // Copy with illegal negative sourceOffset
+      testString.copyTo(destination, -1, destinationOffset, length);
+      fail("Should have thrown an exception when given a negative sourceOffset in "
+          + CLASSNAME);
+    } catch (IndexOutOfBoundsException expected) {
+      // This is success
+    }
+
+    try {
+      // Copy with illegal negative destinationOffset
+      testString.copyTo(destination, 0, -1, length);
+      fail("Should have thrown an exception when given a negative destinationOffset in "
+          + CLASSNAME);
+    } catch (IndexOutOfBoundsException expected) {
+      // This is success
+    }
+
+    try {
+      // Copy with illegal negative size
+      testString.copyTo(destination, 0, 0, -1);
+      fail("Should have thrown an exception when given a negative size in "
+          + CLASSNAME);
+    } catch (IndexOutOfBoundsException expected) {
+      // This is success
+    }
+
+    try {
+      // Copy with illegal too-large sourceOffset
+      testString.copyTo(destination, 2 * testString.size(), 0, length);
+      fail("Should have thrown an exception when the destinationOffset is too large in "
+          + CLASSNAME);
+    } catch (IndexOutOfBoundsException expected) {
+      // This is success
+    }
+
+    try {
+      // Copy with illegal too-large destinationOffset
+      testString.copyTo(destination, 0, 2 * destination.length, length);
+      fail("Should have thrown an exception when the destinationOffset is too large in "
+          + CLASSNAME);
+    } catch (IndexOutOfBoundsException expected) {
+      // This is success
+    }
+  }
+
+  public void testCopyTo_ByteBuffer() {
+    // Same length.
+    ByteBuffer myBuffer = ByteBuffer.allocate(BYTES.length);
+    testString.copyTo(myBuffer);
+    myBuffer.flip();
+    assertEquals(CLASSNAME + ".copyTo(ByteBuffer) must give back the same bytes",
+        backingBuffer, myBuffer);
+
+    // Target buffer bigger than required.
+    myBuffer = ByteBuffer.allocate(testString.size() + 1);
+    testString.copyTo(myBuffer);
+    myBuffer.flip();
+    assertEquals(backingBuffer, myBuffer);
+
+    // Target buffer has no space.
+    myBuffer = ByteBuffer.allocate(0);
+    try {
+      testString.copyTo(myBuffer);
+      fail("Should have thrown an exception when target ByteBuffer has insufficient capacity");
+    } catch (BufferOverflowException e) {
+      // Expected.
+    }
+
+    // Target buffer too small.
+    myBuffer = ByteBuffer.allocate(1);
+    try {
+      testString.copyTo(myBuffer);
+      fail("Should have thrown an exception when target ByteBuffer has insufficient capacity");
+    } catch (BufferOverflowException e) {
+      // Expected.
+    }
+  }
+
+  public void testMarkSupported() {
+    InputStream stream = testString.newInput();
+    assertTrue(CLASSNAME + ".newInput() must support marking", stream.markSupported());
+  }
+
+  public void testMarkAndReset() throws IOException {
+    int fraction = testString.size() / 3;
+
+    InputStream stream = testString.newInput();
+    stream.mark(testString.size()); // First, mark() the end.
+
+    skipFully(stream, fraction); // Skip a large fraction, but not all.
+    assertEquals(
+        CLASSNAME + ": after skipping to the 'middle', half the bytes are available",
+        (testString.size() - fraction), stream.available());
+    stream.reset();
+    assertEquals(
+        CLASSNAME + ": after resetting, all bytes are available",
+        testString.size(), stream.available());
+
+    skipFully(stream, testString.size()); // Skip to the end.
+    assertEquals(
+        CLASSNAME + ": after skipping to the end, no more bytes are available",
+        0, stream.available());
+  }
+
+  /**
+   * Discards {@code n} bytes of data from the input stream. This method
+   * will block until the full amount has been skipped. Does not close the
+   * stream.
+   * <p>Copied from com.google.common.io.ByteStreams to avoid adding dependency.
+   *
+   * @param in the input stream to read from
+   * @param n the number of bytes to skip
+   * @throws EOFException if this stream reaches the end before skipping all
+   *     the bytes
+   * @throws IOException if an I/O error occurs, or the stream does not
+   *     support skipping
+   */
+  static void skipFully(InputStream in, long n) throws IOException {
+    long toSkip = n;
+    while (n > 0) {
+      long amt = in.skip(n);
+      if (amt == 0) {
+        // Force a blocking read to avoid infinite loop
+        if (in.read() == -1) {
+          long skipped = toSkip - n;
+          throw new EOFException("reached end of stream after skipping "
+              + skipped + " bytes; " + toSkip + " bytes expected");
+        }
+        n--;
+      } else {
+        n -= amt;
+      }
+    }
+  }
+
+  public void testAsReadOnlyByteBuffer() {
+    ByteBuffer byteBuffer = testString.asReadOnlyByteBuffer();
+    byte[] roundTripBytes = new byte[BYTES.length];
+    assertTrue(byteBuffer.remaining() == BYTES.length);
+    assertTrue(byteBuffer.isReadOnly());
+    byteBuffer.get(roundTripBytes);
+    assertTrue(CLASSNAME + ".asReadOnlyByteBuffer() must give back the same bytes",
+        Arrays.equals(BYTES, roundTripBytes));
+  }
+
+  public void testAsReadOnlyByteBufferList() {
+    List<ByteBuffer> byteBuffers = testString.asReadOnlyByteBufferList();
+    int bytesSeen = 0;
+    byte[] roundTripBytes = new byte[BYTES.length];
+    for (ByteBuffer byteBuffer : byteBuffers) {
+      int thisLength = byteBuffer.remaining();
+      assertTrue(byteBuffer.isReadOnly());
+      assertTrue(bytesSeen + thisLength <= BYTES.length);
+      byteBuffer.get(roundTripBytes, bytesSeen, thisLength);
+      bytesSeen += thisLength;
+    }
+    assertTrue(bytesSeen == BYTES.length);
+    assertTrue(CLASSNAME + ".asReadOnlyByteBufferTest() must give back the same bytes",
+        Arrays.equals(BYTES, roundTripBytes));
+  }
+
+  public void testToByteArray() {
+    byte[] roundTripBytes = testString.toByteArray();
+    assertTrue(CLASSNAME + ".toByteArray() must give back the same bytes",
+        Arrays.equals(BYTES, roundTripBytes));
+  }
+
+  public void testWriteTo() throws IOException {
+    ByteArrayOutputStream bos = new ByteArrayOutputStream();
+    testString.writeTo(bos);
+    byte[] roundTripBytes = bos.toByteArray();
+    assertTrue(CLASSNAME + ".writeTo() must give back the same bytes",
+        Arrays.equals(BYTES, roundTripBytes));
+  }
+
+  public void testWriteToShouldNotExposeInternalBufferToOutputStream() throws IOException {
+    OutputStream os = new OutputStream() {
+      @Override
+      public void write(byte[] b, int off, int len) {
+        Arrays.fill(b, off, off + len, (byte) 0);
+      }
+
+      @Override
+      public void write(int b) {
+        throw new UnsupportedOperationException();
+      }
+    };
+
+    byte[] original = Arrays.copyOf(BYTES, BYTES.length);
+    testString.writeTo(os);
+    assertTrue(CLASSNAME + ".writeTo() must NOT grant access to underlying buffer",
+        Arrays.equals(original, BYTES));
+  }
+
+  public void testWriteToInternalShouldExposeInternalBufferToOutputStream() throws IOException {
+    OutputStream os = new OutputStream() {
+      @Override
+      public void write(byte[] b, int off, int len) {
+        Arrays.fill(b, off, off + len, (byte) 0);
+      }
+
+      @Override
+      public void write(int b) {
+        throw new UnsupportedOperationException();
+      }
+    };
+
+    testString.writeToInternal(os, 0, testString.size());
+    byte[] allZeros = new byte[testString.size()];
+    assertTrue(CLASSNAME + ".writeToInternal() must grant access to underlying buffer",
+        Arrays.equals(allZeros, backingBuffer.array()));
+  }
+
+  public void testWriteToShouldExposeInternalBufferToByteOutput() throws IOException {
+    ByteOutput out = new ByteOutput() {
+      @Override
+      public void write(byte value) throws IOException {
+        throw new UnsupportedOperationException();
+      }
+
+      @Override
+      public void write(byte[] value, int offset, int length) throws IOException {
+        throw new UnsupportedOperationException();
+      }
+
+      @Override
+      public void writeLazy(byte[] value, int offset, int length) throws IOException {
+        throw new UnsupportedOperationException();
+      }
+
+      @Override
+      public void write(ByteBuffer value) throws IOException {
+        throw new UnsupportedOperationException();
+      }
+
+      @Override
+      public void writeLazy(ByteBuffer value) throws IOException {
+        Arrays.fill(value.array(), value.arrayOffset(), value.arrayOffset() + value.limit(),
+            (byte) 0);
+      }
+    };
+
+    testString.writeTo(out);
+    byte[] allZeros = new byte[testString.size()];
+    assertTrue(CLASSNAME + ".writeTo() must grant access to underlying buffer",
+        Arrays.equals(allZeros, backingBuffer.array()));
+  }
+
+  public void testNewOutput() throws IOException {
+    ByteArrayOutputStream bos = new ByteArrayOutputStream();
+    ByteString.Output output = ByteString.newOutput();
+    testString.writeTo(output);
+    assertEquals("Output Size returns correct result",
+        output.size(), testString.size());
+    output.writeTo(bos);
+    assertTrue("Output.writeTo() must give back the same bytes",
+        Arrays.equals(BYTES, bos.toByteArray()));
+
+    // write the output stream to itself! This should cause it to double
+    output.writeTo(output);
+    assertEquals("Writing an output stream to itself is successful",
+        testString.concat(testString), output.toByteString());
+
+    output.reset();
+    assertEquals("Output.reset() resets the output", 0, output.size());
+    assertEquals("Output.reset() resets the output",
+        EMPTY, output.toByteString());
+  }
+
+  public void testToString() {
+    String testString = "I love unicode \u1234\u5678 characters";
+    ByteString unicode = forString(testString);
+    String roundTripString = unicode.toString(UTF_8);
+    assertEquals(CLASSNAME + " unicode must match", testString, roundTripString);
+  }
+
+  public void testCharsetToString() {
+    String testString = "I love unicode \u1234\u5678 characters";
+    ByteString unicode = forString(testString);
+    String roundTripString = unicode.toString(UTF_8);
+    assertEquals(CLASSNAME + " unicode must match", testString, roundTripString);
+  }
+
+  public void testToString_returnsCanonicalEmptyString() {
+    assertSame(CLASSNAME + " must be the same string references",
+        EMPTY.toString(UTF_8),
+        new NioByteString(ByteBuffer.wrap(new byte[0])).toString(UTF_8));
+  }
+
+  public void testToString_raisesException() {
+    try {
+      EMPTY.toString("invalid");
+      fail("Should have thrown an exception.");
+    } catch (UnsupportedEncodingException expected) {
+      // This is success
+    }
+
+    try {
+      testString.toString("invalid");
+      fail("Should have thrown an exception.");
+    } catch (UnsupportedEncodingException expected) {
+      // This is success
+    }
+  }
+
+  public void testEquals() {
+    assertEquals(CLASSNAME + " must not equal null", false, testString.equals(null));
+    assertEquals(CLASSNAME + " must equal self", testString, testString);
+    assertFalse(CLASSNAME + " must not equal the empty string",
+        testString.equals(EMPTY));
+    assertEquals(CLASSNAME + " empty strings must be equal",
+        EMPTY, testString.substring(55, 55));
+    assertEquals(CLASSNAME + " must equal another string with the same value",
+        testString, new NioByteString(backingBuffer));
+
+    byte[] mungedBytes = mungedBytes();
+    assertFalse(CLASSNAME + " must not equal every string with the same length",
+        testString.equals(new NioByteString(ByteBuffer.wrap(mungedBytes))));
+  }
+
+  public void testEqualsLiteralByteString() {
+    ByteString literal = ByteString.copyFrom(BYTES);
+    assertEquals(CLASSNAME + " must equal LiteralByteString with same value", literal,
+        testString);
+    assertEquals(CLASSNAME + " must equal LiteralByteString with same value", testString,
+        literal);
+    assertFalse(CLASSNAME + " must not equal the empty string",
+        testString.equals(ByteString.EMPTY));
+    assertEquals(CLASSNAME + " empty strings must be equal",
+        ByteString.EMPTY, testString.substring(55, 55));
+
+    literal = ByteString.copyFrom(mungedBytes());
+    assertFalse(CLASSNAME + " must not equal every LiteralByteString with the same length",
+        testString.equals(literal));
+    assertFalse(CLASSNAME + " must not equal every LiteralByteString with the same length",
+        literal.equals(testString));
+  }
+
+  public void testEqualsRopeByteString() {
+    ByteString p1 = ByteString.copyFrom(BYTES, 0, 5);
+    ByteString p2 = ByteString.copyFrom(BYTES, 5, BYTES.length - 5);
+    ByteString rope = p1.concat(p2);
+
+    assertEquals(CLASSNAME + " must equal RopeByteString with same value", rope,
+        testString);
+    assertEquals(CLASSNAME + " must equal RopeByteString with same value", testString,
+        rope);
+    assertFalse(CLASSNAME + " must not equal the empty string",
+        testString.equals(ByteString.EMPTY.concat(ByteString.EMPTY)));
+    assertEquals(CLASSNAME + " empty strings must be equal",
+        ByteString.EMPTY.concat(ByteString.EMPTY), testString.substring(55, 55));
+
+    byte[] mungedBytes = mungedBytes();
+    p1 = ByteString.copyFrom(mungedBytes, 0, 5);
+    p2 = ByteString.copyFrom(mungedBytes, 5, mungedBytes.length - 5);
+    rope = p1.concat(p2);
+    assertFalse(CLASSNAME + " must not equal every RopeByteString with the same length",
+        testString.equals(rope));
+    assertFalse(CLASSNAME + " must not equal every RopeByteString with the same length",
+        rope.equals(testString));
+  }
+
+  private byte[] mungedBytes() {
+    byte[] mungedBytes = new byte[BYTES.length];
+    System.arraycopy(BYTES, 0, mungedBytes, 0, BYTES.length);
+    mungedBytes[mungedBytes.length - 5] = (byte) (mungedBytes[mungedBytes.length - 5] ^ 0xFF);
+    return mungedBytes;
+  }
+
+  public void testHashCode() {
+    int hash = testString.hashCode();
+    assertEquals(CLASSNAME + " must have expected hashCode", EXPECTED_HASH, hash);
+  }
+
+  public void testPeekCachedHashCode() {
+    ByteString newString = new NioByteString(backingBuffer);
+    assertEquals(CLASSNAME + ".peekCachedHashCode() should return zero at first", 0,
+        newString.peekCachedHashCode());
+    newString.hashCode();
+    assertEquals(CLASSNAME + ".peekCachedHashCode should return zero at first",
+        EXPECTED_HASH, newString.peekCachedHashCode());
+  }
+
+  public void testPartialHash() {
+    // partialHash() is more strenuously tested elsewhere by testing hashes of substrings.
+    // This test would fail if the expected hash were 1.  It's not.
+    int hash = testString.partialHash(testString.size(), 0, testString.size());
+    assertEquals(CLASSNAME + ".partialHash() must yield expected hashCode",
+        EXPECTED_HASH, hash);
+  }
+
+  public void testNewInput() throws IOException {
+    InputStream input = testString.newInput();
+    assertEquals("InputStream.available() returns correct value",
+        testString.size(), input.available());
+    boolean stillEqual = true;
+    for (byte referenceByte : BYTES) {
+      int expectedInt = (referenceByte & 0xFF);
+      stillEqual = (expectedInt == input.read());
+    }
+    assertEquals("InputStream.available() returns correct value",
+        0, input.available());
+    assertTrue(CLASSNAME + " must give the same bytes from the InputStream", stillEqual);
+    assertEquals(CLASSNAME + " InputStream must now be exhausted", -1, input.read());
+  }
+
+  public void testNewInput_skip() throws IOException {
+    InputStream input = testString.newInput();
+    int stringSize = testString.size();
+    int nearEndIndex = stringSize * 2 / 3;
+    long skipped1 = input.skip(nearEndIndex);
+    assertEquals("InputStream.skip()", skipped1, nearEndIndex);
+    assertEquals("InputStream.available()",
+        stringSize - skipped1, input.available());
+    assertTrue("InputStream.mark() is available", input.markSupported());
+    input.mark(0);
+    assertEquals("InputStream.skip(), read()",
+        testString.byteAt(nearEndIndex) & 0xFF, input.read());
+    assertEquals("InputStream.available()",
+        stringSize - skipped1 - 1, input.available());
+    long skipped2 = input.skip(stringSize);
+    assertEquals("InputStream.skip() incomplete",
+        skipped2, stringSize - skipped1 - 1);
+    assertEquals("InputStream.skip(), no more input", 0, input.available());
+    assertEquals("InputStream.skip(), no more input", -1, input.read());
+    input.reset();
+    assertEquals("InputStream.reset() succeded",
+        stringSize - skipped1, input.available());
+    assertEquals("InputStream.reset(), read()",
+        testString.byteAt(nearEndIndex) & 0xFF, input.read());
+  }
+
+  public void testNewCodedInput() throws IOException {
+    CodedInputStream cis = testString.newCodedInput();
+    byte[] roundTripBytes = cis.readRawBytes(BYTES.length);
+    assertTrue(CLASSNAME + " must give the same bytes back from the CodedInputStream",
+        Arrays.equals(BYTES, roundTripBytes));
+    assertTrue(CLASSNAME + " CodedInputStream must now be exhausted", cis.isAtEnd());
+  }
+
+  /**
+   * Make sure we keep things simple when concatenating with empty. See also
+   * {@link ByteStringTest#testConcat_empty()}.
+   */
+  public void testConcat_empty() {
+    assertSame(CLASSNAME + " concatenated with empty must give " + CLASSNAME,
+        testString.concat(EMPTY), testString);
+    assertSame("empty concatenated with " + CLASSNAME + " must give " + CLASSNAME,
+        EMPTY.concat(testString), testString);
+  }
+
+  public void testJavaSerialization() throws Exception {
+    ByteArrayOutputStream out = new ByteArrayOutputStream();
+    ObjectOutputStream oos = new ObjectOutputStream(out);
+    oos.writeObject(testString);
+    oos.close();
+    byte[] pickled = out.toByteArray();
+    InputStream in = new ByteArrayInputStream(pickled);
+    ObjectInputStream ois = new ObjectInputStream(in);
+    Object o = ois.readObject();
+    assertTrue("Didn't get a ByteString back", o instanceof ByteString);
+    assertEquals("Should get an equal ByteString back", testString, o);
+  }
+
+  private static ByteString forString(String str) {
+    return new NioByteString(ByteBuffer.wrap(str.getBytes(UTF_8)));
+  }
+}