Computer scienceProgramming languagesJavaWorking with dataMultithreadingSynchronization

Semaphores

Theory

The respiration process

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A pharmaceutical company is trying to develop a medication that can potentially lower the chance of lung cancer by 50%. They have already synthesized the first batch of this drug, but before they start testing it on living things they want to simulate its effect on a virtual model. You are one of the entrusted engineer working on the creation of this model. Your task is to model how carbon and oxygen atoms form CO2 (carbon dioxide) molecules in the process of respiration.

There are two kinds of threads: oxygen and carbon.

There is a barrier where each thread has to wait until a complete molecule can be formed. Carbon and oxygen threads will be given the releaseCarbon and releaseOxygen methods respectively, which will allow them to pass the barrier. These threads should pass the barrier in groups of three, and they must immediately bond with each other to form a CO2 molecule. You must guarantee that all the threads from one molecule bond before any other threads from the next molecule do.

In other words:

  • If a carbon thread arrives at the barrier when no oxygen threads are present, it must wait for 2 oxygen threads.
  • If an oxygen thread arrives at the barrier when no other threads are present, it must wait for a carbon thread and another oxygen thread.

Don't worry about matching the threads up explicitly; the threads don't necessarily know which other threads they are paired up with. The key is that threads pass the barriers in complete sets; so, if we examine the sequence of threads that bind and divide them into groups of three, each group should contain one carbon and two oxygen threads.

Write the synchronization code for oxygen and carbon atoms that enforces these constraints.

Note: if the input is "'OOC",

"OCO", "COO" are also valid answers.

Likewise, if the input is "OOOCOC",

"COOOCO", "COOOOC", "OCOCOO", "OCOOCO", "OCOOOC", "OOCCOO", "OOCOCO", "COOCOO"

are also valid answers.

Sample Input 1: 

OOC

Sample Output 1: 

OOC

Sample Input 2: 

OCO

Sample Output 2: 

OOC
Write a program in Java 17
import java.util.*;
import java.util.concurrent.Semaphore;

class CO2 {
// Add your fields here

// Update the method
public void carbon(StringBuffer molecules) throws InterruptedException {
molecules.append('C'); // Do not change the line
}

// Update the method
public void oxygen(StringBuffer molecules) throws InterruptedException {
molecules.append('O'); // Do not change the line
}
}
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