Thread: Object help

I'm making a program and I can't get it to display the results properly in the displayInterest method in the InterestCalculatorTest class.

InterestCalculator7 Class

public class InterestCalculator7
{
		// Class Level Variables (Data Fields / Properties)
	public double principalAmount;
	public double interestRate;
	public int term1;
 
 
		  // ** Constructors **
		  // No-Argument constructor
	  public InterestCalculator7()
	  {
		  this.principalAmount = 0.0;
		  this.interestRate = -1.0;
		  this.term1 = 0;
	  }
 
 
	  public InterestCalculator7(double principalAmount, double interestRate, int term1)
	  {
	    this.principalAmount = principalAmount;
	    this.interestRate = interestRate;
	    this.term1 = term1;
	  }
 
		  // ** Methods **
		   public double calculateSimpleInterest()
		  {
			  double calculateSimpleInterest = ((principalAmount)*(interestRate/100.0)*(term1/12.0));
				return calculateSimpleInterest;
		  }
 
		   public  double calculateCompoundInterest(double term1)
		   {
			     double calculateCompoundInterest = (principalAmount*Math.pow((1.0+((interestRate/100.0)/term1)),(term1*(term1/12.0))))-principalAmount;
				return calculateCompoundInterest;
			 }
 
 
}

InterestCalculatorTest class

public class InterestCalculatorTester
{
	public static void main(String[] args)
	{
		double principal;
	    double interest;
	    int term;
 
	   do{
		   principal = getPrincipalAmount();
			interest = getInterestRate();
			term = getTerm();
			double calculationType = getCalculationType(principal,interest,term);
 
			InterestCalculator7 interestCalculator = new InterestCalculator7(principal, interest, term);
 
			if (calculationType == 1)
			{
				calculationType = interestCalculator.calculateSimpleInterest();
				displayInterest(interestCalculator, "Simple", calculationType);
			}
			else if (calculationType == 2)
			{
				calculationType = interestCalculator.calculateCompoundInterest(12.0);
				displayInterest(interestCalculator, "Monthly", calculationType);
			}
			else if (calculationType == 3)
			{
				calculationType = interestCalculator.calculateCompoundInterest(365.0);
				displayInterest(interestCalculator, "Daily", calculationType);
			}
			else 
			{
				calculationType = interestCalculator.calculateCompoundInterest(52.0);
				displayInterest(interestCalculator, "Weekly", calculationType);
			}
 
 
			} while (askYesNo("Calculate another loan interest (Yes/No)"));
 
			System.out.print("Thanks for using Interest Calculator!");
	  }
 
 
 
	/** Round **/
	  public  double round(double numb1, double numb2) {
	    double round = ((double) Math.round(numb1*(Math.pow(10, numb2)))/(Math.pow(10, numb2)));;
		return round;
	  }
 
 
	    /** display interest **/
	  public static void displayInterest(InterestCalculator7 object, String type, double calculationType) {
 
 
		System.out.println("Principal Amount    Interest Rate    Term    Calculation Type    Calculated Interest    Total Repayment");
		System.out.println("----------------    -------------    ----    ----------------    -------------------    ---------------");
		System.out.print(getPrincipalAmount()+"                ");
		System.out.print(+getInterestRate()+"           ");
		System.out.print(+getTerm()+"           ");
		System.out.print(+type+"            ");
		System.out.print(+calculationType+"              ");
		System.out.println(+(getPrincipalAmount() + calculationType));
	  }
 
	  /** Get principal amount **/
	  public static double getPrincipalAmount() {
		  Scanner input = new Scanner(System.in);
		  double numb2 = 1;
		 do{System.out.print("Enter Loan Amount: ");
		   numb2 = input.nextDouble();
		   if(numb2 > 0);
 
		   		else{	
			    		System.out.println("Data Error: Loan amount must be greater than zero. You entered " +numb2);
		   		}		
			   }while (numb2 < 0);
		return numb2;
	  }
 
	  /** Get interest rate **/
	  public static double getInterestRate() {
		  Scanner input = new Scanner(System.in);
		  double numb2=1;
		  do{System.out.print("Enter Yearly Interest Rate (1 to 100 percent): ");
		    numb2 = input.nextDouble(); 
		  double getInterestRate = 0;
		 if (numb2 >= 0 && numb2 <= 100)
		  getInterestRate = numb2;
		   		else{	
			    		System.out.println("Data Error: Interest rate must be greater than or equal to zero and less than or equal to 100. You entered " +numb2);
		   		}		
			   }while (numb2 <= 0 || numb2 >= 100);
		return numb2;
	  }
 
	  /** Get term **/
	  public static int getTerm() {
		  Scanner input = new Scanner(System.in);
		  int numb2=1;
		  do{System.out.print("Enter the Term (in months): ");
		    numb2 = input.nextInt();
		  double getTerm = 0;
		  if (numb2 > 0)
		  getTerm = numb2;
		   		else{	
			    		System.out.println("Data Error: Loan amount must be greater than zero. You entered " +numb2);
		   		}		
			   }while (numb2 <= 0);
		return numb2;
	  }
 
	  /** Get calculation type **/
	  public static double getCalculationType(double numb1, double numb2, double numb3) {
		  Scanner input = new Scanner(System.in);
		  int type;
		 do{
			  System.out.print("Enter Interest Calculation Type (1 – Simple, 2 – Monthly Compounded, 3 – Daily Compounded, 4 - Weekly Compounded):");
		      type = input.nextInt();
		      double principle =  numb1;
			  double interest= numb2;
			  double term= numb3;
 
 
		 } while (type !=1 && type !=2 && type !=3 && type !=4);
 
	return type;
	  }
 
	  /**ask yes or no **/
	  public static boolean askYesNo(String question) {
		  Scanner input = new Scanner(System.in);
		  String enteredText;
		  boolean isAnswerValid;
 
		  do{
			  isAnswerValid = false;
			  System.out.println(question);
			  enteredText = input.nextLine();
 
			  if (enteredText.length() > 0)
			  {
				  enteredText = enteredText.toUpperCase();
 
				  if(enteredText.equals("YES") || enteredText.equals("Y") || enteredText.equals("NO") || enteredText.equals("N"))
				  {
					  isAnswerValid = true;
				  }
			  }
 
			  if(isAnswerValid == false)
			  {
				  System.out.println("Please enter 'Yes' or 'No'?");
			  }
 
		  } while(isAnswerValid == false);
 
		  if(enteredText.equals("YES") || enteredText.equals("Y"))
		  {
			  return true;
		  }
 
		  return false;
	  }
}

This is the correct output is supposed to be

Enter loan amount: 1375
Enter yearly interest rate (0 to 100 percent): 1.175
Enter the term in number of months: 7
Enter Interest Calculation Type (1 – Simple, 2 – Monthly Compounded, 3 – Daily Compounded, 4 – Weekly Compounded): 1
Principal Amount Interest Rate Term Calculation Type Calculated Interest Total Repayment Amount
---------------- ------------- ---- ---------------- ------------------- ----------------------
$1375.0 1.175 7 Simple $9.42448 $1384.42
Calculate another loan interest (Yes/No)? n
Thank you for using the Interest Calculator!

I need to take the principal amount, Interest rate, and term from the interestCalculator7. I'm just confused on how to call the values of the principal amount, interest rate, and term and use them in the displayInterest method

public static void displayInterest(InterestCalculator7 object, String type, int calculationType) {
 
 
		System.out.println("Principal Amount    Interest Rate    Term    Calculation Type    Calculated Interest    Total Repayment");
		System.out.println("----------------    -------------    ----    ----------------    -------------------    ---------------");
		System.out.print(getPrincipalAmount()+"                ");
		System.out.print(+getInterestRate()+"           ");
		System.out.print(+getTerm()+"           ");
		System.out.print(word1+"            ");
		System.out.print(+calculationType+"              ");
		System.out.println(+(getPrincipalAmount() + calculationType));

The current output looks like this

Enter Loan Amount: 10
Enter Yearly Interest Rate (1 to 100 percent): 10
Enter the Term (in months): 10
Enter Interest Calculation Type (1 – Simple, 2 – Monthly Compounded, 3 – Daily Compounded, 4 - Weekly Compounded):1
Principal Amount Interest Rate Term Calculation Type Calculated Interest Total Repayment
---------------- ------------- ---- ---------------- ------------------- ---------------
Enter Loan Amount:

It doesn't input any of the values that the user inputs when asked and doesn't do the calculations and the Do while loop doesn't prompt the user to "enter another loan? (yes/no)

Here's what I have, hopefully this works.

InterestCalculator class

public class InterestCalculator7
{
		// Class Level Variables (Data Fields / Properties)
	public double principalAmount;
	public double interestRate;
	public int term1;
 
 
		  // ** Constructors **
		  // No-Argument constructor
	  public InterestCalculator7()
	  {
		  this.principalAmount = 0.0;
		  this.interestRate = -1.0;
		  this.term1 = 0;
	  }
 
 
	  public InterestCalculator7(double principalAmount, double interestRate, int term1)
	  {
	    this.principalAmount = principalAmount;
	    this.interestRate = interestRate;
	    this.term1 = term1;
	  }
 
		  // ** Methods **
		   public double calculateSimpleInterest()
		  {
			  double calculateSimpleInterest = ((principalAmount)*(interestRate/100.0)*(term1/12.0));
				return calculateSimpleInterest;
		  }
 
		   public  double calculateCompoundInterest(double term1)
		   {
			     double calculateCompoundInterest = (principalAmount*Math.pow((1.0+((interestRate/100.0)/term1)),(term1*(term1/12.0))))-principalAmount;
				return calculateCompoundInterest;
			 }
 
 
}

InterestCalculatortester class

import java.util.Scanner;
public class InterestCalculatorTester
{
	public static void main(String[] args)
	{
		double principal;
	    double interest;
	    int term;
 
	   do{
 
		   principal = getPrincipalAmount();
		   interest = getInterestRate();
		   term = getTerm();
		   int type = getCalculationType();
		   InterestCalculator7 interestCalculator = new InterestCalculator7(principal, interest, term);
 
 
			double totalInterest;
			if (type == 1)
			{
				totalInterest = interestCalculator.calculateSimpleInterest();
				displayInterest(interestCalculator, "Simple", type);
			}
			else if (type == 2)
			{
				totalInterest = interestCalculator.calculateCompoundInterest(12.0);
				displayInterest(interestCalculator, "Monthly", type);
			}
			else if (type == 3)
			{
				totalInterest = interestCalculator.calculateCompoundInterest(365.0);
				displayInterest(interestCalculator, "Daily", type);
			}
			else 
			{
				totalInterest = interestCalculator.calculateCompoundInterest(52.0);
				displayInterest(interestCalculator, "Weekly", type);
			}
 
 
			} while (askYesNo("Calculate another loan interest (Yes/No)"));
 
			System.out.print("Thanks for using Interest Calculator!");
	  }
 
 
 
	/** Round **/
	  public  double round(double numb1, double numb2) {
	    double round = ((double) Math.round(numb1*(Math.pow(10, numb2)))/(Math.pow(10, numb2)));;
		return round;
	  }
 
 
	    /** display interest **/
	  public static void displayInterest(InterestCalculator7 object, String word1, int calculationType) {
 
 
		System.out.println("Principal Amount    Interest Rate    Term    Calculation Type    Calculated Interest    Total Repayment");
		System.out.println("----------------    -------------    ----    ----------------    -------------------    ---------------");
		System.out.print(+getPrincipalAmount()+"                ");
		System.out.print(+getInterestRate()+"           ");
		System.out.print(+getTerm()+"           ");
		System.out.print(word1+"            ");
		System.out.print(+calculationType+"              ");
		System.out.println(+(getPrincipalAmount() + calculationType));
	  }
 
	  /** Get principal amount **/
	  public static double getPrincipalAmount() {
		  Scanner input = new Scanner(System.in);
		  double numb2 = 1;
		 do{System.out.print("Enter Loan Amount: ");
		   numb2 = input.nextDouble();
		   if(numb2 > 0);
 
		   		else{	
			    		System.out.println("Data Error: Loan amount must be greater than zero. You entered " +numb2);
		   		}		
			   }while (numb2 < 0);
		return numb2;
	  }
 
	  /** Get interest rate **/
	  public static double getInterestRate() {
		  Scanner input = new Scanner(System.in);
		  double numb2=1;
		  do{System.out.print("Enter Yearly Interest Rate (1 to 100 percent): ");
		    numb2 = input.nextDouble(); 
		  double getInterestRate = 0;
		 if (numb2 >= 0 && numb2 <= 100)
		  getInterestRate = numb2;
		   		else{	
			    		System.out.println("Data Error: Interest rate must be greater than or equal to zero and less than or equal to 100. You entered " +numb2);
		   		}		
			   }while (numb2 <= 0 || numb2 >= 100);
		return numb2;
	  }
 
	  /** Get term **/
	  public static int getTerm() {
		  Scanner input = new Scanner(System.in);
		  int numb2=1;
		  do{System.out.print("Enter the Term (in months): ");
		    numb2 = input.nextInt();
		  double getTerm = 0;
		  if (numb2 > 0)
		  getTerm = numb2;
		   		else{	
			    		System.out.println("Data Error: Loan amount must be greater than zero. You entered " +numb2);
		   		}		
			   }while (numb2 <= 0);
		return numb2;
	  }
 
	  /** Get calculation type **/
	  public static int getCalculationType() {
		  Scanner input = new Scanner(System.in);
		  int type;
		 do{
			  System.out.print("Enter Interest Calculation Type (1 – Simple, 2 – Monthly Compounded, 3 – Daily Compounded, 4 - Weekly Compounded):");
		      type = input.nextInt();
		 } while (type !=1 && type !=2 && type !=3 && type !=4);
 
	return type;
	  }
 
	  /**ask yes or no **/
	  public static boolean askYesNo(String question) {
		  Scanner input = new Scanner(System.in);
		  String enteredText;
		  boolean isAnswerValid;
 
		  do{
			  isAnswerValid = false;
			  System.out.println(question);
			  enteredText = input.nextLine();
 
			  if (enteredText.length() > 0)
			  {
				  enteredText = enteredText.toUpperCase();
 
				  if(enteredText.equals("YES") || enteredText.equals("Y") || enteredText.equals("NO") || enteredText.equals("N"))
				  {
					  isAnswerValid = true;
				  }
			  }
 
			  if(isAnswerValid == false)
			  {
				  System.out.println("Please enter 'Yes' or 'No'?");
			  }
 
		  } while(isAnswerValid == false);
 
		  if(enteredText.equals("YES") || enteredText.equals("Y"))
		  {
			  return true;
		  }
 
		  return false;
	  }
}

By studying your program I see that there are lots of things you didn't do quite well.
When you display you information, you are not displaying any data there, rather you are asking the user to enter the data again.
What you need to do is. After collecting all the necessary information from the user, pass the information to the InterestCalculator7 class through its constructor.
write severall getmethod in interestcalculator7 class to call these saved information.
And in your displaying code, call the getter methods of the class.

I think I have it, except when the program compiles I am just getting 0.0 for the output. The current output is doing

Enter Loan Amount: 12
Enter Yearly Interest Rate (1 to 100 percent): 23
Enter the Term (in months): 24
Enter Interest Calculation Type (1 – Simple, 2 – Monthly Compounded, 3 – Daily Compounded, 4 - Weekly Compounded):1
Principal Amount Interest Rate Term Calculation Type Calculated Interest Total Repayment
---------------- ------------- ---- ---------------- ------------------- ---------------
0.0 0.0 0.0 Simple 1 1.0
Calculate another loan interest (Yes/No)
no
Thanks for using Interest Calculator!

My new InterestCalculatorTester class is

import java.util.Scanner;
public class InterestCalculatorTester
{
	public static void main(String[] args)
	{
		double principal;
	    double interest;
	    int term;
 
	   do{
 
		   principal = getPrincipalAmount();
		   interest = getInterestRate();
		   term = getTerm();
		   int type = getCalculationType();
		   InterestCalculator7 interestCalculator = new InterestCalculator7(principal, interest, term);
 
 
			double totalInterest;
			if (type == 1)
			{
				totalInterest = interestCalculator.calculateSimpleInterest();
				displayInterest(interestCalculator, "Simple", type);
			}
			else if (type == 2)
			{
				totalInterest = interestCalculator.calculateCompoundInterest(12.0);
				displayInterest(interestCalculator, "Monthly", type);
			}
			else if (type == 3)
			{
				totalInterest = interestCalculator.calculateCompoundInterest(365.0);
				displayInterest(interestCalculator, "Daily", type);
			}
			else 
			{
				totalInterest = interestCalculator.calculateCompoundInterest(52.0);
				displayInterest(interestCalculator, "Weekly", type);
			}
 
 
			} while (askYesNo("Calculate another loan interest (Yes/No)"));
 
			System.out.print("Thanks for using Interest Calculator!");
	  }
 
 
 
	/** Round **/
	  public  double round(double numb1, double numb2) {
	    double round = ((double) Math.round(numb1*(Math.pow(10, numb2)))/(Math.pow(10, numb2)));;
		return round;
	  }
 
 
	    /** display interest **/
	  public static void displayInterest(InterestCalculator7 object, String word1, int calculationType) {
 
 
		System.out.println("Principal Amount    Interest Rate    Term    Calculation Type    Calculated Interest    Total Repayment");
		System.out.println("----------------    -------------    ----    ----------------    -------------------    ---------------");
		System.out.print(+InterestCalculator7.getPrincipal()+"                ");
		System.out.print(+InterestCalculator7.getInterest()+"           ");
		System.out.print(+InterestCalculator7.getTerm()+"           ");
		System.out.print(word1+"            ");
		System.out.print(+calculationType+"              ");
		System.out.println(+(InterestCalculator7.getPrincipal() + calculationType));
	  }
 
	  /** Get principal amount **/
	  public static double getPrincipalAmount() {
		  Scanner input = new Scanner(System.in);
		  double numb2 = 1;
		 do{System.out.print("Enter Loan Amount: ");
		   numb2 = input.nextDouble();
		   if(numb2 > 0);
 
		   		else{	
			    		System.out.println("Data Error: Loan amount must be greater than zero. You entered " +numb2);
		   		}		
			   }while (numb2 < 0);
		return numb2;
	  }
 
	  /** Get interest rate **/
	  public static double getInterestRate() {
		  Scanner input = new Scanner(System.in);
		  double numb2=1;
		  do{System.out.print("Enter Yearly Interest Rate (1 to 100 percent): ");
		    numb2 = input.nextDouble(); 
		  double getInterestRate = 0;
		 if (numb2 >= 0 && numb2 <= 100)
		  getInterestRate = numb2;
		   		else{	
			    		System.out.println("Data Error: Interest rate must be greater than or equal to zero and less than or equal to 100. You entered " +numb2);
		   		}		
			   }while (numb2 <= 0 || numb2 >= 100);
		return numb2;
	  }
 
	  /** Get term **/
	  public static int getTerm() {
		  Scanner input = new Scanner(System.in);
		  int numb2=1;
		  do{System.out.print("Enter the Term (in months): ");
		    numb2 = input.nextInt();
		  double getTerm = 0;
		  if (numb2 > 0)
		  getTerm = numb2;
		   		else{	
			    		System.out.println("Data Error: Loan amount must be greater than zero. You entered " +numb2);
		   		}		
			   }while (numb2 <= 0);
		return numb2;
	  }
 
	  /** Get calculation type **/
	  public static int getCalculationType() {
		  Scanner input = new Scanner(System.in);
		  int type;
		 do{
			  System.out.print("Enter Interest Calculation Type (1 – Simple, 2 – Monthly Compounded, 3 – Daily Compounded, 4 - Weekly Compounded):");
		      type = input.nextInt();
		 } while (type !=1 && type !=2 && type !=3 && type !=4);
 
	return type;
	  }
 
	  /**ask yes or no **/
	  public static boolean askYesNo(String question) {
		  Scanner input = new Scanner(System.in);
		  String enteredText;
		  boolean isAnswerValid;
 
		  do{
			  isAnswerValid = false;
			  System.out.println(question);
			  enteredText = input.nextLine();
 
			  if (enteredText.length() > 0)
			  {
				  enteredText = enteredText.toUpperCase();
 
				  if(enteredText.equals("YES") || enteredText.equals("Y") || enteredText.equals("NO") || enteredText.equals("N"))
				  {
					  isAnswerValid = true;
				  }
			  }
 
			  if(isAnswerValid == false)
			  {
				  System.out.println("Please enter 'Yes' or 'No'?");
			  }
 
		  } while(isAnswerValid == false);
 
		  if(enteredText.equals("YES") || enteredText.equals("Y"))
		  {
			  return true;
		  }
 
		  return false;
	  }
}

My new InterestCalculator7 class is

 
public class InterestCalculator7
{
		// Class Level Variables (Data Fields / Properties)
	public double principalAmount;
	public double interestRate;
	public int term1;
 
 
		  // ** Constructors **
		  // No-Argument constructor
	  public InterestCalculator7()
	  {
		  double principal = 0.0;
		  double interest = -1.0;
		  double term1 = 0;
	  }
 
 
	  public InterestCalculator7(double principalAmount, double interestRate, int term1)
	  {
	    double principal = principalAmount;
	    double interest= interestRate;
	    int term = term1;
	  }
 
	    public static double getPrincipal(){
	    	double principal = 0;
			return principal;
	    }
 
	    public static double getInterest(){
	    	double interest = 0;
			return interest;
	    }
 
	    public static double getTerm(){
	    	double term = 0;
			return term;
	    }
 
 
 
		  // ** Methods **
		   public double calculateSimpleInterest()
		  {
			  double calculateSimpleInterest = ((principalAmount)*(interestRate/100.0)*(term1/12.0));
				return calculateSimpleInterest;
		  }
 
		   public  double calculateCompoundInterest(double term1)
		   {
			     double calculateCompoundInterest = (principalAmount*Math.pow((1.0+((interestRate/100.0)/term1)),(term1*(term1/12.0))))-principalAmount;
				return calculateCompoundInterest;
			 }
 
 
}

I feel like I did something wrong when I was setting them?

I see you have already passed the information to the InterestCalculator7 class. Simply write a getter method in the InterestCalculator7 class. user object to call those data.

--- Update ---

you are using InterestCalculator7, write object not InterestCalculator in the displayinterest method

I'm just confused on how to write the getter method..

Also I think there is something wrong with you interest calculator. When you enter 25000 in principal amount and 15% APR, the interest paid is way too much. That doesnt happen in real world.

--- Update ---

To write getter method, in your InterestCalculator7 class, write a new method just like calculatesimpleinterest with a return statement for principal. It just a 2 line code. The moderator doesn't allow me to write code here.

--- Update ---

public double getprincipal()
{return principalAmount;}

I tried that and it's still not pulling the user input

{
		// Class Level Variables (Data Fields / Properties)
	public static double principalAmount;
	public static double interestRate;
	public static int term1;
 
 
		  // ** Constructors **
		  // No-Argument constructor
	  public InterestCalculator7()
	  {
		  this.principalAmount = 0.0;
		  this.interestRate = -1.0;
		  this.term1 = 0;
	  }
 
 
	  public InterestCalculator7(double principalAmount, double interestRate, int term1)
	  {
		  double principal = principalAmount;
		double interest= interestRate;
	    int term = term1;
	  }
 
	  public static double getPrincipal()
	  {return principalAmount;}
 
	  public static double getInterestRate()
	  {return interestRate;}
 
	  public static double getTerm()
	  {return term1;}
 
 
 
		  // ** Methods **
		   public double calculateSimpleInterest()
		  {
			  double calculateSimpleInterest = ((principalAmount)*(interestRate/100.0)*(term1/12.0));
				return calculateSimpleInterest;
		  }
 
		   public  double calculateCompoundInterest(double term1)
		   {
			     double calculateCompoundInterest = (principalAmount*Math.pow((1.0+((interestRate/100.0)/term1)),(term1*(term1/12.0))))-principalAmount;
				return calculateCompoundInterest;
			 }
 
 
}

did you change your displayInterest methods?
Replace that InterestCalculator7 with just "object".
like object.getPincipal()
Replace all in this methods and it should work.