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Homework 2: Concurrent Programming

• Modify the implementation of the SimpleQueue class, given in the lectures. Replace the rem() method with a get() method that blocks (waits) if the queue is currently emptly. You should use the standard Java wait() and notify() methods for this.
• This queue may be used as a channel for communication between threads. Rename your queue class to Channel; rename the the add() method to send(); rename the get() method to recv().
• Write a Java program with two threads, and one channel. A "producer" thread sends a series of messages to a "consumer" thread through the channel. The consumer thread should print the messages it receives.
• Write another Java program with two threads, and two channels: a "client" thread sends a series of messages to a "server" thread using the first channel. The client expects to receive a reply after each send. The server thread receives the client's messages and sends some extended (or otherwise altered) messages back to the client, using the second channel. The client should print the messages it sends, and the messages it receives back.
• All threads should run in the same virtual machine. Do not use sockets, or any other utility classes like pipes! "Messages" may be simple strings like "message 1", "message 2", etc. Send the source of your Java classes to the address below, preferably in a zip file. You should not need to write more than about 200 lines of code.
• Mail your code to Bryan Carpenter with a due date of Sunday February 8. You can contact me for clarifications, if necessary.