/**
*文件名是ComputeLoan.java
*計算貸款支付總額
*/
導入javax . swing . joptionpane;
公共類計算機{
//主方法
公共靜態void main(String [] agrs) {
//輸入年利率
string anunanalinterestratestring = joptionpane . showinputdialog(" Please input "+
"年度利率,例如7.8 ");
//將字符串轉換為雙精度
double annualInterestRate = double . parse double(anunalInterestRateString);
//將年利率轉換為月利率
double monthly interestate = annual interestate/1200;
System.out.println("年利率為"+annual interestrate);
System.out.println("月利率為"+monthly interest ");
//輸入年數
string numofyearstring = joptionpane . showinputdialog(" Please input "+
"年數,例如5 ");
//將字符串轉換為整數
int numOfYears = integer . parse int(numofyearstring);
System.out.println("年數為"+numOfYears);
//輸入貸款總額
string totalLoanInput = joptionpane . showinputdialog("請輸入貸款總額"+
“,例如9899888.2”);
//要雙精度轉換的字符串
double total loan = double . parse double(totalLoanInput);
System.out.println("貸款總額為"+貸款總額");
//計算每月付款的總額
double total monthly payment = total loan * monthly interestate/
(1-1/(math . pow(1+monthly interest,numOfYears * 12)));
double total yearly payment = total monthly payment * 12 * numOfYears;
//格式保留小數點後兩位數
totalMonthlyPayment =(int)(totalMonthlyPayment * 100)/100.0;
totalYearlyPayment =(int)(totalYearlyPayment * 100)/100.0;
//顯示結果
String output = "每月付款是\n "
+total monthly payment+" \n貸款支付總額為\ n "
+total yearly payment;
joptionpane . showmessagedialog(null,output);
}
}