DeadlockSim

DeadlockSim.java

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;

//-----------------------------------------------------------------
// Program by: Sam Fader and Annabella Lopez
//
// This program was created to simulate deadlock prevention using the
// Banker's Algorithm. Processes must declare the maximum number of
// instances of each resource type and may not exceed the total number
// or resources in the system.
//
// Before allocating resources the following must be known:
// (1) How much of each resource each process may request.
// (2) How much of each resource each process is currently holding.
// (3) How much of each resource the system has available.
//
// *Notes*
// -Due to the difficulty of working with 2d arrays we used
//  InputStreamReader along with BufferReader for efficiency.
//-------------------------------------------------------------------

public class DeadlockSim {
	public static void main(String[] args)throws IOException{
		
		InputStreamReader scan = new InputStreamReader(System.in);
		BufferedReader obj = new BufferedReader(scan);
		
		int numOfProcess, numOfResources;
		
		System.out.println("Enter number of processes: ");
		numOfProcess = Integer.parseInt(obj.readLine());
		
		System.out.println("Enter number or resources: ");
		numOfResources = Integer.parseInt(obj.readLine());
		
		//----------------------------------------
		// Reads in number of resource instances
		// for storage into an array
		//-----------------------------------------
		int availableResources[] = new int[numOfResources];
		
		for(int resourceNum = 0; resourceNum < numOfResources; resourceNum++){
			System.out.println("Enter number of instances for Resource " + resourceNum + ": ");
			availableResources[resourceNum] = Integer.parseInt(obj.readLine());
		}//end for
		
		
		System.out.println("Allocation Requirements: ");
		
		//----------------------------------------
		// Asks user in advance for resources that
		// their processes will require.
		//----------------------------------------
		int allocation[][] = new int[numOfProcess][numOfResources];
		
		for(int x = 0; x < numOfProcess; x++)
			for(int y = 0; y < numOfResources; y++){
			System.out.println("How many instances of Resource " + y + " does Process " + x + " want to allocate? ");
			allocation[x][y] = Integer.parseInt(obj.readLine());
			
		}//end for
		
		System.out.println("Max Requirements: ");
		
		//----------------------------------------
		// Asks user in advance for max # of 
		// resource instances for each process.
		//----------------------------------------
		int maxResources[][] = new int[numOfProcess][numOfResources];
		
		for(int x = 0; x < numOfProcess; x++)
			for(int y = 0; y < numOfResources; y++){
				System.out.println("Max instances for Resource "+ y +"for Process "+ x + " ?");	
				maxResources[x][y]=Integer.parseInt(obj.readLine());
				
			}//end for
		
		//--------------------------------------------
		// Created a 2d array for future check method 
		// to see if the process meets all the
		// requirements for resource allocation.
		//--------------------------------------------
		int resourcesNeeded[][] = new int[numOfProcess][numOfResources];
		
		for(int x = 0; x < numOfProcess; x++)
			for(int y = 0; y < numOfResources; y++){
				resourcesNeeded[x][y] = (maxResources[x][y] - allocation[x][y]);
			}//end for
	}//end main
}//end DeadlockSim