Question

更新：我从未解决过以所需的特定格式输出日期的问题，但程序的其余部分仍然有效。在搞乱了time.format类后，我确实找到了几种不同格式输出日期的方法，并且我能够使用除列表中最后一个应该属于time.format类但不幸的是我从来没有弄清楚如何实现它。但是，这是一个很好的（在我看来）计算兴趣的简单程序的例子。我已经阅读了很多关于getter和setter的批评，但他们似乎对这个程序工作得很好。请注意，我仍在学习Java和编程。

package accountproject;

// two imports needed for date and time
import java.time.format.*;
import java.time.*;
// import standard exception error text
import java.text.ParseException;
// import EVERYTHING!
import java.util.*;

public class Account {

private static int id = 0;
private static double balance = 0;
private static double annualInterestRate = 0;
private static ZonedDateTime dateCreated;
private static double MonthlyInterestRate = annualInterestRate/12;

public Account()
{
    // empty constructor
}

public Account(int id, double balance, double annualInterestRate, ZonedDateTime dateCreated) {
    super();
    Account.id = 0;
    Account.balance = 0;
    Account.annualInterestRate = 4.5;
}

public int getId() {
    return id;
}

public void setId(int id) {
    Account.id = id;
}

public static double getBalance(double d) {
    return balance;
}

public void setBalance(double balance) {
    Account.balance = balance;
}

public double getAnnualInterestRate() {
    return annualInterestRate;
}

public void setAnnualInterestRate(double annualInterestRate) {
    Account.annualInterestRate = annualInterestRate;
}

public static ZonedDateTime ConvertStringToDate(String dateNow) {
    try
{
    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("E MMM dd HH:mm:ss z yyyy", Locale.ENGLISH);
    ZonedDateTime date = ZonedDateTime.parse(dateNow, formatter);

    return date;
}
 catch (DateTimeParseException e)
{
    System.out.println(e);
}
    ZonedDateTime date = null;
    return date;
}

public static double getMonthlyInterestRate(double annualInterestRate2) {

    double temp = annualInterestRate2/12;

    MonthlyInterestRate = temp;

    return MonthlyInterestRate;
}

public static double getMonthlyInterest(double newBalance2) {

    double temp = 100/MonthlyInterestRate;

    double temp2 = newBalance2/temp;

    double temp3 = newBalance2 + temp2;

    newBalance2 = temp3;

    return temp2;
}

public static double deposit(double balance, double deposit) {

    double temp = balance + deposit;

    balance = temp;

    return balance;
}

public static double withdrawal(double balance, double withdrawal) {

    double temp = balance - withdrawal;

    balance = temp;

    return balance;
}

    public static void main(String[] args) throws ParseException {

        // establish a scanner and set example values
        Scanner stdin = new Scanner(System.in);
        id = 1122;
        balance = 20000;
        MonthlyInterestRate = .375;
        double withdrawal = 2500;
        double deposit = 3000;

        double balanceExp = deposit(balance,deposit);
        balanceExp = withdrawal(balanceExp,withdrawal);
        double balanceExp2 = getMonthlyInterest(balanceExp);
        double monthlyInterest = balanceExp2;

        String dateExp = "Fri Oct 06 16:10:59 GMT 2017";
        dateCreated = ConvertStringToDate(dateExp);

        System.out.println("SAMPLE: Account ID " + id + " with a balance of $" + balanceExp
                 + ",\nhas accrued $" + monthlyInterest + " in interest and was opened on " 
                + dateCreated + ".");

        System.out.println("Please enter the ID number:");

        // get the id number input
        id = stdin.nextInt();
        stdin.nextLine();

        System.out.println("Typically, the original balance will be $20,000.00.\nPlease enter the balance:");

        // get the starting balance input
        balance = stdin.nextInt();
        stdin.nextLine();

        double newBalance = balance;

        Account.getBalance(20000.00);

        System.out.println("Please enter the deposit amount:");

        // ensure deposit is set to 0 before getting input
        deposit = 0.00;

        // get the deposit amount from input
        deposit = stdin.nextDouble();
        stdin.nextLine();

        newBalance = deposit(balance, deposit);

        System.out.println("Please enter the withdrawal amount:");

        // ensure withdrawal is set to 0 before getting input
        withdrawal = 0.00;

        // get the deposit amount from input
        withdrawal = stdin.nextDouble();
        stdin.nextLine();

        double newBalance2 = withdrawal(newBalance, withdrawal);
        double newBalance3 = getMonthlyInterest(newBalance2);
        double MonthlyInterest = newBalance3;

        print(id, newBalance2, MonthlyInterest, dateCreated);

        stdin.close();
    }

    public static void print(int id, double newBalance2, double MonthlyInterest, ZonedDateTime dateCreated2)
    {
            System.out.println("To verify: the Account ID is " + id + " with a balance of $" + newBalance2
                    + ",\nhas accrued $" + MonthlyInterest + " in interest, and was opened on " + dateCreated2 + ".");
    }
}

Answer 1

我认为问题出在主线上。

withdrawl(balance, withdrawl);

您必须将方法的返回值分配给变量。

double currentBalance = withdrawl(balance, withdrawl);
print(id, currentBalance, MonthlyInterestRate, dateCreated);

Answer 2

我花了很多时间来重新学习这个。我没有意识到java 8有新的java.time

这里有很多变化。希望这有助于在代码中注释所有更改

import java.time.format.*;
import java.time.*;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;

public class Account {

private static int id = 0;
private static double balance = 0;
private static double annualInterestRate = 0;
private static Date dateCreated;
private static double MonthlyInterestRate = annualInterestRate/12;


public Account()
{
    // empty constructor
}

/**
 * @param id
 * @param balance
 * @param annualInterestRate
 * @param dateCreated
 * regular constructors
 */

public Account(int id, double balance, double annualInterestRate, Date dateCreated) {
    super();
    Account.id = 0;
    Account.balance = 0;
    Account.annualInterestRate = 4.5;
    Account.dateCreated = dateCreated;
}

public int getId() {
    return id;
}

public void setId(int id) {
    Account.id = id;
}

public static double getBalance(double d) {
    return balance;
}

public void setBalance(double balance) {
    Account.balance = balance;
}

public double getAnnualInterestRate() {
    return annualInterestRate;
}

public void setAnnualInterestRate(double annualInterestRate) {
    Account.annualInterestRate = annualInterestRate;
}

public static LocalDate ConvertStringToDate(String dateNow) {
    try
{
    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("MM d yyyy", Locale.ENGLISH);
    LocalDate date = LocalDate.parse(dateNow, formatter);
    System.out.println(date);
    return date;
}
 catch (DateTimeParseException e)
{
    System.out.println(e);
}
LocalDate date = null;
return date;



}



public static double getMonthlyInterestRate(double annualInterestRate2) {

    double temp = annualInterestRate2/12;

    MonthlyInterestRate = temp;

    return MonthlyInterestRate;

}

public double getMonthlyInterest() {

    double temp = 100/annualInterestRate;

    double temp2 = getBalance(0)/temp;

    double temp3 = balance + temp2;

    System.out.println(temp3);

    return temp3;

}

public static double deposit(double balance, double deposit) {

    double temp = balance + deposit;

    balance = temp;

    return balance;
}

public static double withdrawl(double balance, double withdrawl) {

    double temp = balance - withdrawl;

    balance = temp;

    return balance;
}

    public static void main(String[] args) throws ParseException {
        //create Scanner 1 time. no need to create over and over
        Scanner stdin = new Scanner(System.in);
        id = 1122;
        balance = 20000;
        MonthlyInterestRate = .375;

        System.out.println("SAMPLE: Account ID " + id + " with a balance of " + balance + " "
                + "and a monthly interest rate of " + MonthlyInterestRate + " opened on " +
                dateCreated + ".");

        System.out.println("Please enter the ID number:");

        id = stdin.nextInt();
        // consume the /n
        stdin.nextLine();

        System.out.println("Typically, the original balance will be $20,000.00.\nPlease enter the balance:");



        balance = stdin.nextInt();
        // consume the /n
        stdin.nextLine();

        double newBalance = balance;

        Account.getBalance(20000.00);

        System.out.println("Please enter the date created like: MM d yyyy");


        // assign your string to your scanned object
        String dateNow = stdin.nextLine();
        //catch your returned date
        LocalDate dateCreated = ConvertStringToDate(dateNow);

        System.out.println("Please enter the deposit amount:");



        double deposit = 0.00;

        deposit = stdin.nextDouble();
        // consume the /n
        stdin.nextLine();

        newBalance = deposit(balance, deposit);

        System.out.println("Please enter the withdrawl amount:");



        double withdrawl = 0.00;

        withdrawl = stdin.nextDouble();
        // consume the /n
        stdin.nextLine();

        double newBalance2 = withdrawl(newBalance, withdrawl);

        double annualInterestRate2 = 4.5;

        double MonthlyInterestRate2 = getMonthlyInterestRate(annualInterestRate2);

        // pass your local date
        print(id, newBalance2, MonthlyInterestRate2, dateCreated);
    }

    public static void print(int id, double balance, double MonthlyInterestRate2, LocalDate dateCreated)
    {
            System.out.println("To verify: the Account ID is " + id + " with a balance of $" + balance + " "
                    + "and a monthly interest rate of " + MonthlyInterestRate2 + "% opened on " +
                    dateCreated + ".");
    }
 }

Answer 3

我从来没有弄清楚如何设置格式以获得我教授想要的日期，但我得到了100％，所以我猜到最后它并没有那么重要。感谢Jeremiah Stillings，我感谢所有的帮助。这就是我最终的结果：

 package accountproject;

 // two imports needed for date and time
 import java.time.format.*;
 import java.time.*;
 // import standard exception error text
 import java.text.ParseException;
 // import EVERYTHING!
 import java.util.*;

 public class Account {

private static int id = 0;
private static double balance = 0;
private static double annualInterestRate = 0;
private static ZonedDateTime dateCreated;
private static double MonthlyInterestRate = annualInterestRate/12;

public Account()
{
    // empty constructor
}

/**
 * @param id
 * @param balance
 * @param annualInterestRate
 * @param dateCreated
 * regular constructors
 */

public Account(int id, double balance, double annualInterestRate, ZonedDateTime dateCreated) {
    super();
    Account.id = 0;
    Account.balance = 0;
    Account.annualInterestRate = 4.5;
}

public int getId() {
    return id;
}

public void setId(int id) {
    Account.id = id;
}

public static double getBalance(double d) {
    return balance;
}

public void setBalance(double balance) {
    Account.balance = balance;
}

public double getAnnualInterestRate() {
    return annualInterestRate;
}

public void setAnnualInterestRate(double annualInterestRate) {
    Account.annualInterestRate = annualInterestRate;
}

public static ZonedDateTime ConvertStringToDate(String dateNow) {
    try
{
    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("E MMM dd HH:mm:ss z yyyy", Locale.ENGLISH);
    ZonedDateTime date = ZonedDateTime.parse(dateNow, formatter);

    return date;
}
 catch (DateTimeParseException e)
{
    System.out.println(e);
}
    ZonedDateTime date = null;
    return date;
}

public static double getMonthlyInterestRate(double annualInterestRate2) {

    double temp = annualInterestRate2/12;

    MonthlyInterestRate = temp;

    return MonthlyInterestRate;
}

public static double getMonthlyInterest(double newBalance2) {

    double temp = 100/MonthlyInterestRate;

    double temp2 = newBalance2/temp;

    double temp3 = newBalance2 + temp2;

    newBalance2 = temp3;

    return temp2;
}

public static double deposit(double balance, double deposit) {

    double temp = balance + deposit;

    balance = temp;

    return balance;
}

public static double withdrawal(double balance, double withdrawal) {

    double temp = balance - withdrawal;

    balance = temp;

    return balance;
}

    public static void main(String[] args) throws ParseException {

        // establish a scanner and set example values
        Scanner stdin = new Scanner(System.in);
        id = 1122;
        balance = 20000;
        MonthlyInterestRate = .375;
        double withdrawal = 2500;
        double deposit = 3000;

        double balanceExp = deposit(balance,deposit);
        balanceExp = withdrawal(balanceExp,withdrawal);
        double balanceExp2 = getMonthlyInterest(balanceExp);
        double monthlyInterest = balanceExp2;

        String dateExp = "Fri Oct 06 16:10:59 GMT 2017";
        dateCreated = ConvertStringToDate(dateExp);

        System.out.println("SAMPLE: Account ID " + id + " with a balance of $" + balanceExp
                 + ",\nhas accrued $" + monthlyInterest + " in interest and was opened on " 
                + dateCreated + ".");

        System.out.println("Please enter the ID number:");

        // get the id number input
        id = stdin.nextInt();
        stdin.nextLine();

        System.out.println("Typically, the original balance will be $20,000.00.\nPlease enter the balance:");

        // get the starting balance input
        balance = stdin.nextInt();
        stdin.nextLine();

        double newBalance = balance;

        Account.getBalance(20000.00);

        System.out.println("Please enter the deposit amount:");

        // ensure deposit is set to 0 before getting input
        deposit = 0.00;

        // get the deposit amount from input
        deposit = stdin.nextDouble();
        stdin.nextLine();

        newBalance = deposit(balance, deposit);

        System.out.println("Please enter the withdrawal amount:");

        // ensure withdrawal is set to 0 before getting input
        withdrawal = 0.00;

        // get the deposit amount from input
        withdrawal = stdin.nextDouble();
        stdin.nextLine();

        double newBalance2 = withdrawal(newBalance, withdrawal);
        double newBalance3 = getMonthlyInterest(newBalance2);
        double MonthlyInterest = newBalance3;

        print(id, newBalance2, MonthlyInterest, dateCreated);

        stdin.close();
    }

    public static void print(int id, double newBalance2, double MonthlyInterest, ZonedDateTime dateCreated2)
    {
            System.out.println("To verify: the Account ID is " + id + " with a balance of $" + newBalance2
                    + ",\nhas accrued $" + MonthlyInterest + " in interest, and was opened on " + dateCreated2 + ".");
    }
 }

如何使用getter和setter打印特定的日期和时间

3 个答案: