Trouble finding out where I went wrong in my beginner java project concerning methods, class and equations

if it helps, here is my full code on one of my classes

public class BankAccount { private String name; private String account; private double checkingAccount; private double savingsInterestRate; private double savingsAccount; private int savingsDays; private double totalEarnedInterest;

 public BankAccount()
 {

 }//end BankAccount()

 public BankAccount(String name, String account)
 {
    setName(name);
    setAccount(account);
 }//end BankAccount(String, String)

 public BankAccount(String name, String account, double amount)
 {
    setName(name);
    setAccount(account);
    setChecking(amount);
 }//end BankAccount(String, String, double)

 public void setName(String Name)
 {
    this.name = Name;
 }//end setName(String)

 public void setAccount(String acc)
 {
    this.account = acc;
 }//end setAccount

 public void setChecking(double amount)
 {
    if(amount >=0.00)
    {
        this.checkingAccount = amount;
    }
 }//end setChecking(double)

 public void setSavings(double amount)
 {
    if(amount >=0.0)
    {
        this.savingsAccount = amount;
    }
 }//end setSavings(double)

 public void setDays(int num)
 {
    if(num >= 0)
    {
        savingsDays= num;
    }
 }//end setDays

public void setSavingsInterestRate(double rate)
{
    if(rate >= 0.0)
    {
        savingsInterestRate= rate;
    }
}//end setSavingsInterestRate(double)

public String getName()
{
    String strFullName;
    strFullName = this.name;

    return strFullName;
}
//end getName()

public String getAccount()
{
    String strAccountNum;
    strAccountNum= this.account;

    return strAccountNum;
}//end getAccount()

public double getChecking()
{
    double dAmount;
    dAmount = this.checkingAccount;

    return dAmount;
}//end getChecking

public double getSavings()
{
    double dSavAm;
    dSavAm = this.savingsAccount;

    return dSavAm;
}//end getSavings

public double getSavingsIntrest()
{
    double dSavIn;
    dSavIn = this.savingsInterestRate;

    return dSavIn;
}//end getSavingsIntrest

public double getTotalEarnedInterest()
{
    double dTotal;
        dTotal= this.savingsInterestRate * this.savingsAccount;
    return dTotal;
}//end getTotalEarnedInterest

public int getDays()
{
    int iResult;

    iResult = this.savingsDays;
    return iResult;

}//end getDays

public int addDays(int iNumDays)
{

    int iDays = 0;

    if(iNumDays > 0)
    {
        this.savingsDays =iNumDays + this.savingsDays;
        iDays = this.savingsDays;
    }

    return iDays;
}//end addDays

public double addInterest()
{
    int i;
    double dNewInterest = 0.0;
    int iNewDays = 0;
    for(i=30; i<iNewDays; i++)
    {


        dNewInterest =(this.savingsInterestRate * this.savingsAccount)*this.savingsDays/360.0;



    }
    return dNewInterest;
}//end addInterest

public double depositAmount(double amount, char type)
{
double dNewAmount = 0.0;
int iWrong;
    if(amount>=0.0)
    {
        if(type == 'C')
        {
            dNewAmount = (amount) + this.getChecking();
        }
        else
        {
            if(type == 'S' )
            {
                dNewAmount = (amount) + this.getSavings();
            }
            else
            {
                dNewAmount = -1.0;
            }
        }
    }

        return dNewAmount;

}//end depositAmount

public double withdrawAmount(double amount, char type)
{
    double dMoney = 0.0;

    if(amount>=0.0)
    {
        if(type == 'C')
        {
            if(amount> getChecking())
            {
                dMoney= this.getChecking() - amount;
            }
            else{
                dMoney = 0.0;
            }

        }
        else{
            if(type =='S')
            {
                if(amount> getChecking())
                {
                    dMoney = this.getChecking() - amount;
                }
                else{
                    dMoney=0.0;
                }
            }
        }
    }
    else{
        dMoney = -1.0;
    }

    return dMoney;
}//end withdrawAmount

public static void clearScreen()
{
    System.out.print("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n");
    System.out.print("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n");   
}//end clearScreen()


public String toString()
{

String  strInfo = "";   //
    strInfo+="\n\n\tAccount Information";
    strInfo+="\n\t                     Name: " + this.name;
    strInfo+="\n\t                  Account: " + this.account;
    strInfo+="\n\t                 Checking: " + checkingAccount;
    strInfo+="\n\t                   Saving: " + savingsAccount;
    strInfo+="\n\t     Saving Interest Rate: " + savingsInterestRate;
    strInfo+="\n\t         Days Accumulated: " + savingsDays;


    return strInfo;

}//end toString()

}//end BankAccount

/r/learnprogramming Thread