ObjectInputStream.java (read): AND byte with 0xff to make result unsigned.
* java/io/ObjectInputStream.java (read): AND byte with 0xff to make
result unsigned.
(read (byte[], int, int)): Only call readNextBlock() if the block
buffer would actually be overrun. Increment blockDataPosition.
(callReadMethod): Propagate exceptions from invocation target.
* java/io/ObjectOutputStream.java (callWriteMethod): Propagate
exceptions from invocation target.