42 lines
1.2 KiB
Java
42 lines
1.2 KiB
Java
package nachos.threads;
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import nachos.machine.*;
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/**
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* A <i>communicator</i> allows threads to synchronously exchange 32-bit
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* messages. Multiple threads can be waiting to <i>speak</i>,
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* and multiple threads can be waiting to <i>listen</i>. But there should never
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* be a time when both a speaker and a listener are waiting, because the two
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* threads can be paired off at this point.
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*/
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public class Communicator {
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/**
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* Allocate a new communicator.
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*/
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public Communicator() {
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}
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/**
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* Wait for a thread to listen through this communicator, and then transfer
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* <i>word</i> to the listener.
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*
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* <p>
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* Does not return until this thread is paired up with a listening thread.
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* Exactly one listener should receive <i>word</i>.
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*
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* @param word the integer to transfer.
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*/
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public void speak(int word) {
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}
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/**
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* Wait for a thread to speak through this communicator, and then return
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* the <i>word</i> that thread passed to <tt>speak()</tt>.
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*
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* @return the integer transferred.
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*/
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public int listen() {
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return 0;
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}
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}
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