### Question:
ByteVector { public ByteVector putLong(final long longValue) { int currentLength = length; if (currentLength + 8 > data.length) { enlarge(8); } byte[] currentData = data; int intValue = (int) (longValue >>> 32); currentData[currentLength++] = (byte) (intValue >>> 24); currentData[currentLength++] = (byte) (intValue >>> 16); currentData[currentLength++] = (byte) (intValue >>> 8); currentData[currentLength++] = (byte) intValue; intValue = (int) longValue; currentData[currentLength++] = (byte) (intValue >>> 24); currentData[currentLength++] = (byte) (intValue >>> 16); currentData[currentLength++] = (byte) (intValue >>> 8); currentData[currentLength++] = (byte) intValue; length = currentLength; return this; } ByteVector();  ByteVector(final int initialCapacity);   ByteVector(final byte[] data); ByteVector putByte(final int byteValue); ByteVector putShort(final int shortValue); ByteVector putInt(final int intValue); ByteVector putLong(final long longValue); ByteVector putUTF8(final String stringValue); ByteVector putByteArray(
      final byte[] byteArrayValue, final int byteOffset, final int byteLength);  }### Answer:
@Test public void testPutLong() { ByteVector byteVector = new ByteVector(0); byteVector.putLong(0x0102030405060708L); assertArrayEquals(new byte[] {1, 2, 3, 4, 5, 6, 7, 8}, toArray(byteVector)); }