Answers to CSC207H1Y Quiz 1 V1

LocalAreaNetwork.java

package network;

public class LocalAreaNetwork extends Network
{

    public static String whatAmI = "I am a LAN";
    public static int numCreated;

    public int numNodes;
    public char firstLetter = 'L';
    public String location;

    public LocalAreaNetwork(int numNodes, String location)
    {
        super( numNodes );
        this.location = location;
        numCreated++;
    }

    @Override
    public String toString()
    {
        return firstLetter + " is for LAN";
    }

    public boolean equals(Network x)
    {
        return x instanceof LocalAreaNetwork && x.numNodes == this.numNodes;
    }
}

Network.java

package network;

public class Network
{

    public static String whatAmI = "I am a Network";
    public static int numCreated;

    public int numNodes;
    public char firstLetter = 'N';

    public Network(int numNodes)
    {
        this.numNodes = numNodes;
        numCreated++; 
    }

    public String printNumNodes()
    {
        return "The number of nodes in this network is " + numNodes;
    }

    @Override
    public String toString()
    {
        return firstLetter + " is for Network";
    }

    public boolean equals(Network x)
    {
        return x instanceof Network;
    }
}

Quiz1Demo.java

package network;

public class Quiz1Demo
{

    private static int numQuestion;

    public static void main(String[] args)
    {
        Network n1 = new Network( 200 );
        Network n2 = new LocalAreaNetwork( 300, "UTM" );
        LocalAreaNetwork n3 = new LocalAreaNetwork( 400, "UTSC" );
        
        // Q1 
        println( Network.numCreated );

        // Q2
        println( LocalAreaNetwork.numCreated );

        // Q3
        println( n3.location );

        // Q4
        // println( n2.location );
        println( "error: cannot find symbol" );

        // Q5
        println( n1.numNodes );

        // Q6
        println( n2.numNodes );

        // Q7
        println( n3.numNodes );

        // Q8
        println( n1 );

        // Q9
        println( n2 );

        // Q10
        println( n3 );

        // Q11
        println( n1.printNumNodes() );

        // Q12
        println( n3.printNumNodes() );

        // Q13
        println( n1.equals( n2 ) );

        // Q14
        println( n2.equals( n3 ) );

        // Q15
        println( n3.equals( n2 ) );

        // Q16
        // Proof by example. Since, the question asks: If at least one instance where they are the "same" while their locations differ exists.
        println( n3.equals( new LocalAreaNetwork( 0, "some location" ) ) );

        // Q17
        println( "no" ); // By logic

        Integer x = new Integer( 3 );
        int y = 4;
        Integer z = x + y;
        int q = x + y;

        // Q18
        println( z == q );

        // Q19
        println( z.equals( q ) );

        // Q20
        // println( q.equals( z ) );
        println( "error: int cannot be dereferenced" );
    }
    
    private static<T> void println(T arg)
    {
        numQuestion++;
        System.out.println( "Question #" + numQuestion );
        System.out.println( arg );
    }
}