Java程序错误:找不到符号
我迷路了!我正在学习一门在线Java课程,需要so协助完成这项作业。 一旦程序被编译,就会产生找不到符号错误Java程序错误:找不到符号,java,swing,Java,Swing,我迷路了!我正在学习一门在线Java课程,需要so协助完成这项作业。 一旦程序被编译,就会产生找不到符号错误 Loan loan = new Loan(annualInterestRate, numberOfYears, loanAmount); symbol: class Loan location: class ChangeRequest5 我已经尝试在类ChangeRequest5中创建类Loan,还尝试了getMonthlyPaymen的方法。该程序运行一个干净且成功的构建,并为利
Loan loan = new Loan(annualInterestRate, numberOfYears, loanAmount);
symbol: class Loan
location: class ChangeRequest5
我已经尝试在类ChangeRequest5中创建类Loan,还尝试了getMonthlyPaymen的方法。该程序运行一个干净且成功的构建,并为利率、贷款期限和贷款金额创建用户输入,但不会显示该表
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
public class ChangeRequest5 {
public static void main(String[] args) {
Object[] rateList = new Object[9];
int i = 0;
for (double rate = 5; rate <=6; rate += 1.0 /4)
rateList[i++] = new Double (rate);
Object annualInterestRateObject = JOptionPane.showInputDialog(
null, "Select annual interest rate:" , "Mortgage Calculator" ,
JOptionPane.QUESTION_MESSAGE, null, rateList, null);
double annualInterestRate =
((Double)annualInterestRateObject).doubleValue();
Object[]yearList = {new Integer(7), new Integer(15), new Integer(30)};
Object numberOfYearsObject = JOptionPane.showInputDialog(
null, "Select number of years:" , "Mortgage Calculator" ,
JOptionPane.QUESTION_MESSAGE, null, yearList, null);
int numberOfYears = ((Integer)numberOfYearsObject).intValue();
String loanAmountString = JOptionPane.showInputDialog(null,
"Enter loan amount, for example 200000 for $200000.00" , "Mortgage Calculator" ,
JOptionPane.QUESTION_MESSAGE);
double loanAmount = Double.parseDouble(loanAmountString);
Loan loan = new Loan(annualInterestRate, numberOfYears, loanAmount);
double monthlyPayment = loan.getMonthlyPayment();
String output = "Interest Rate:" + annualInterestRate +
"%" + "Number of Years:" + numberOfYears + " Loan Amount: $"
+ loanAmount;
output += " Monthly Payment: " + "$" + (int)(monthlyPayment * 100) /100.0;
output += " Totaly Payment $" + (int) (monthlyPayment * 12 * numberOfYears
* 100) / 100.0;
double monthlyInterestRate = annualInterestRate / 1200;
double balance = loanAmount;
double interest;
double principal;
output += " Payment#\tInterest\rPrincipal\tBalance";
for (i = 1; i <= numberOfYears * 12; i++){
interest = (int)(monthlyInterestRate * balance * 100) / 100.0;
principal = (int)((monthlyPayment - interest) * 100) / 100.0;
balance = (int)((balance - principal) * 100) / 100.0;
output += i + "\t" + interest + "\t" + principal + "\t" + balance;
}
JScrollPane jsp = new JScrollPane(new JTextArea(output));
jsp.setPreferredSize(new java.awt.Dimension(400, 200));
JOptionPane.showMessageDialog(null, jsp,
"Mortgage Calculator" , JOptionPane.INFORMATION_MESSAGE, null);
}
}
import javax.swing.JOptionPane;
导入javax.swing.JScrollPane;
导入javax.swing.JTextArea;
公共类变更请求5{
公共静态void main(字符串[]args){
对象[]比率列表=新对象[9];
int i=0;
对于(double rate=5;rate除非“Loan”在同一个包中,否则您还需要有一个“Loan”的导入语句除非它在同一个包中,否则您还需要有一个“Loan”的导入语句您是否有一个文件Loan.java
在同一个包中定义类Loan
工作
如果它位于不同的包中,则需要将其导入到其他.java文件中:
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import package2.Loan;
public class ChangeRequest5 {
您是否有一个文件Loan.java
在同一个包中定义一个类Loan
如果它位于不同的包中,则需要将其导入到其他.java文件中:
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import package2.Loan;
public class ChangeRequest5 {
我看不到你的代码中有任何地方定义了一个名为Loan
的类。我看不到你的代码中有任何地方定义了一个名为Loan
的类。我试过了,也收到了错误:线程“main”java.lang中的异常。UnsupportedOperationException:尚未在Loan中实现。(Loan.java:13)在ChangeRequest5.main(ChangeRequest5.java:38)上,java结果:1构建成功(总时间:13秒),因此我返回到原始代码查看它。任何人都可以告诉我哪里出错了。谢谢我尝试了,并收到了错误:线程“main”java.lang中的异常。UnsupportedOperationException:尚未在借出时实现。(Loan.java:13)在ChangeRequest5.main(ChangeRequest5.java:38)上的java结果:1构建成功(总时间:13秒)所以我返回到原始代码,查看它。任何人都可以告诉我哪里出了问题。谢谢。但是如果贷款也在默认包中声明,你就不会。也许吧。但是如果贷款也在默认包中声明,你就不会。