Question

In BlueJ, create a project called Lab6

• Create a class called LineSegment –Note: test changes as you go
• Copy the code for LineSegment given below into the class.
• Take a few minutes to understand what the class does. Besides the mutators and accessors, it has a method called print, that prints the end points of the line segment in the form: (x, y) to (x, y)
• You will have to write two methods in the LineSegment class. There is information on black board under this week to help with the following methods.
  • determineQuadrant - this method determines if the line segment is completely in a quadrant and returns a String (“Quadrant 1”, “Quadrant 2”, “Quadrant 3”, or “Quadrant 4”) representing the quadrant. If it is not completely in a quadrant it returns the string “Crosses an Axis”. There are no formal parameters.
  • computeLength– returns the length of the line segment created by the points. There are no formal parameters
• • Test the line segment class to make sure the methods you added work correctly.

Code for class LineSegment

public class LineSegment
{
    private int x1;
    private int y1;
    private int x2;
    private int y2;

    public LineSegment()
    {
    }
    public LineSegment(int x1, int y1, int x2, int y2)
    {
        this.x1 = x1;
        this.y1 = y1;
        this.x2 = x2;
        this.y2 = y2;

    }
    public void setPoint1(int x, int y)
    {
        this.x1 = x;
        this.y1 = y;
    }
    public void setPoint2(int x, int y)
    {
        this.x2 = x;
        this.y2 = y;
    } 
    public int getPoint1X()
    {
        return x1;
    }
    public int getPoint1Y()
    {
        return y1;
    }
    public int getPoint2X()
    {
        return x2;
    }
    public int getPoint2Y()
    {
        return y2;
    }        
    //Prints the point in the format (x1, y1) to (x2, y2)
    public void print()
    {
        System.out.print("(" + x1 + ", " + y1 + ") to (" + x2 + ", " + y2 + ")");
    }
}    

Once you have the class working

• Create a class called Main – copy the code below into the class
• Follow the comments to write the main method and the enterLineSegmentEndPoints in the Main class.
• The program, when finished, should create the output given
• When you have it running correctly, upload the LineSegment and Main class to zybook and submit it for grading.

Code for class Main

import java.util.Scanner;
public class Main
{
    public static Scanner kb = new Scanner(System.in);

    public static void main(String [] args)
    {
        String input; // this variable used to allow the 
                      // use to type Y or N when asked about
                      // changing point 
        // As you develop your program, add any variables
        // you may need here 



        // Declare an object of the Line Segment class
        // Use the constructor with no formal parameters 



        // You are to finish the rest of main to create the output given. 
        // This program will also have a method called enterLineSegmentEndPoints
        // that allows the user to enter the end points of a line segment. The header
        // for the method is given below main.
        // Declare any variables you may need in the section above
        // Some suggestions might be:
        // First get the loop going that will continue asking if there is
        // another line segment until the user types in anything other than Y
        // Next get the method to enter the endpoints working - see output for formatting
        // Then compute the length of the line segment using the method you wrote in the class
        // Next for the quadrant, you might want to store the string returned from the method 
        // class and then check the first character to determine what to print
        // Finally put in the code that will print the total number of line segments
        // entered after the user indicates they are done.

        // NOTE: Get little pieces to work at a time - do NOT type it all in at once











     }

     // Add the code to this method wrapper so that it allows the user to enter the 
     // end points of the line segments as shown on the output
     public static void enterLineSegmentEndPoints(LineSegment line)
     {

     }

}

A sample output is given

Enter the x and y coordinate of the first end point: 2 9
Enter the x and y coordinate of the second end point: 14 6

Line Segment: (2, 9) to (14, 6)
The length of the line segment is: 12.37
The line segment is completely in Quadrant 1

Would you like to enter another line segment (y/n): Y

Enter the x and y coordinate of the first end point: -4 8
Enter the x and y coordinate of the second end point: -7 -3

Line Segment: (-4, 8) to (-7, -3)
The length of the line segment is: 11.40
The line segment Crosses an Axis

Would you like to enter another line segment (y/n): y

Enter the x and y coordinate of the first end point: 3 -7
Enter the x and y coordinate of the second end point: 21 -14

Line Segment: (3, -7) to (21, -14)
The length of the line segment is: 19.31
The line segment is completely in Quadrant 4

Would you like to enter another line segment (y/n): n

You entered a total of 3 line segments

Information for finding Quadrants Information for finding distance ???????? ??????? ??? ?????? = √(?2 − ?1 ) 2 + (?2 − ?1 ) 2 You may also need the method in the Math class: Math.sqrt(num) and/or Math.pow(base, exponent)

Answer 1

Code: LineSegment.java

package demo;

public class LineSegment
{
private int x1;
private int y1;
private int x2;
private int y2;

// default constructor
public LineSegment()
{
  
}
  
// setter and getter to get and set the values
// sets x1 and y1 value
public void setPoint1(int x, int y)
{
this.x1 = x;
this.y1 = y;
}
// sets x2 and y2 value
public void setPoint2(int x, int y)
{
this.x2 = x;
this.y2 = y;
}
  
// return x1 value
public int getPoint1X()
{
return x1;
}
// return y1
public int getPoint1Y()
{
return y1;
}
// return x2 value
public int getPoint2X()
{
return x2;
}
// return y2 value
public int getPoint2Y()
{
return y2;
}
//Prints the point in the format (x1, y1) to (x2, y2)
public void print()
{
System.out.print("Line Segment: (" + x1 + ", " + y1 + ") to (" + x2 + ", " + y2 + ")");
}
}

Code: Main.java

package demo;

import java.util.Scanner;

public class Main
{
public static Scanner kb = new Scanner(System.in);

public static void main(String [] args)
{
String input; // this variable used to allow the
// use to type Y or N when asked about
// changing point
  
  
do {
  
   // Declare an object of the Line Segment class
// Use the constructor with no formal parameters
LineSegment p1 = new LineSegment();
// call the method to read values
enterLineSegmentEndPoints(p1);

// call the calculateDistance to calculate distance
double distace =(float)calculateDistance(p1);
System.out.printf("The length of the line segment is : %.2f ",distace);
System.out.println();

// checks if the two points lies in the same Quadrant or not
if(checkQuadrant(p1.getPoint1X(), p1.getPoint1Y()) == checkQuadrant(p1.getPoint2X(), p1.getPoint2Y())) {
   System.out.println("The line segment is completely in "+ checkQuadrant(p1.getPoint1X(), p1.getPoint1Y()));
   System.out.println();
}
// else if points do not lie on same quadrant
else {
  
   System.out.println("The line segment Crosses an Axis");
   System.out.println();
}
  
// ask user want to enter another points
System.out.println("Would you like to enter another line segment (y/n):");
// read yes or no from user
input = kb.next();
}while(input.equals("Y") || input.equals("y"));

}
// method to read values
public static void enterLineSegmentEndPoints(LineSegment p1)
{
   int x1,y1,x2,y2;
   System.out.println("Enter the x and y coordinate of the first end point: ");
// read values from user
x1 = kb.nextInt();
y1 = kb.nextInt();
// set the values
p1.setPoint1(x1, y1);
  
System.out.println("Enter the x and y coordinate of the second end point: ");
// read values from user
x2 = kb.nextInt();
y2 = kb.nextInt();
// set values
p1.setPoint2(x2, y2);
  
System.out.println();
// call the print function
p1.print();
System.out.println();

}

// this method will calculate distance and return value
public static double calculateDistance(LineSegment p1) {
//     get the values
   float x1 = p1.getPoint1X();
   float x2 = p1.getPoint2X();
   float y1 = p1.getPoint1Y();
   float y2 = p1.getPoint2Y();
     
//     distance calculation
   double distance = Math.sqrt(((x2-x1)*(x2-x1))+((y2-y1)*(y2-y1)));

   return distance;
}

// this method checks if the both points lies in same quadrant or not
public static String checkQuadrant(float x , float y) {
     
//     checks for Q1
   if(x>0 && y>0) {
       return "Quadrant 1";
   }
     
//     checks for Q2
   else if(x<0 && y>0) {
       return "Quadrant 2";
   }
     
//     checks for Q4
   else if(x>0 && y<0) {
       return "Quadrant 4";
   }
     
//     checks for Q3
   else if(x<0 && y<0) {
       return "Quadrant 3";
   }
       return null;
     
}

}