This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
These two I/O classes don't go together. An ObjectInputStream expects data in a specific binary format. A PrintWriter writes text. Either use an ObjectOutputStream on the sending side, or use a Reader on the reading side and parse the data appropriately.
Java has two kinds of I/O classes. Streams are for reading and writing binary data (bytes). Readers and Writers are for reading and writing text (characters), which are converted from and to bytes using a character encoding.