我一直在：
非法开始表达，';“预期System.exit（0），并达到 解析时的文件结尾
这是对它的假设和代码的描述。
要解决的问题：
我应该在课外学习多少？
问题：
你的同学需要帮助。这是他们上大学的第一年，他们需要确定他们需要多少小时才能获得好成绩。
Study Hrs Per Week Per Credit Grade
5: A,
4: B,
3: C,
2: D,
0: F,
项目规格：
以下是我的代码：
import javax.swing.JOptionPane; //Needed for the dialogue box
/**
This program shows the student the grade they will receive
or how much to study for a certain grade.
*/
public class MoultonAlainaProject1
{
public static void main(String[] args)
{
string wantedGrade, desiredGrade, name, input;
char finalGrade;
int gradeA = 5;
int gradeB = 4;
int gradeC = 3;
int gradeD = 2;
int gradeF = 0;
float studyHrs;
int creditHrs, userChoice;
//Scanner for keyboard input
Scanner keyboard = new Scanner(System.in);
name = JOptionPane.showInputDialog("Please enter your name.");
input = JOptionPane.showInputDialog("How many credit hours do you plan on taking this semester?");
creditHrs = integer.parseInt(input);
input = JOption.showInputDialog("If you would like to know the amount of hours you should study for the amount of" +
"credit hours press 1. If you would like to know the grade you would receive by" +
"entering the amount of hours you plan to study press 2.");
userChoice = integer.parseInt(input);
if (userChoice == 1)
{
desiredGrade = JOptionPane.showInputDialog("Enter the grade you would like to receive.");
if (desiredGrade == 'A' || 'a')
{
wantedGrade = gradeA;
}
else
{
if (desiredGrade == 'B' ||'b')
{
wantedGrade = gradeB;
}
else
{
if (desiredGrade == 'C' || 'c')
{
wantedGrade = gradeC;
}
else
{
if (desiredGrade == 'D' || 'd')
{
wantedGrade = gradeD;
}
else
{
if (desiredGrade == 'F' || 'f')
{
wantedGrade = gradeF;
}
else
{
System.out.printIn("Error: you have not entered a valid input.");
}
}
}
}
}
studyHrs = wantedGrade * creditHrs;
}
else
{
if (userChoice == 2)
{
input = JOptionPane.showInputDialog("Enter the amount of hours you plan to study a week.");
studyHrs = integer.parseInt(input);
wantedGrade = studyHrs/creditHrs;
if (wantedGrade >= 5)
{
finalGrade = "A";
}
else
{
if (wantedGrade >= 4)
{
finalGrade = "B";
}
else
{
if (wantedGrade >= 3)
{
finalGrade = "C";
}
else
{
if (wantedGrade >= 2)
{
finalGrade = "D";
}
else
{
if (wantedGrade < 2)
{
finalGrade = "F";
}
}
}
}
}
JOptionPane.showMessageDialog(null, name+ ", you are taking " +creditHrs+ "credit hours, you should study " +studyHrs+ " hours a week to receive " +finalGrade+ " in your classes."
System.exit(0);
}
}
我已经检查了很多次，但我可能在某处遗漏了某些东西
答案 0 :(得分：1)
您有大约20个编译时错误
我看到缺少导入，用小写字母写的字符串，未闭合的括号，
未闭合的花括号，将字符串值赋给char变量等。
见下文并修复它们。
Description Resource Path Location Type
Type mismatch: cannot convert from String to char MoultonAlainaProject1.java /TEST/src line 107 Java Problem
Type mismatch: cannot convert from String to char MoultonAlainaProject1.java /TEST/src line 101 Java Problem
Type mismatch: cannot convert from String to char MoultonAlainaProject1.java /TEST/src line 95 Java Problem
Type mismatch: cannot convert from String to char MoultonAlainaProject1.java /TEST/src line 89 Java Problem
integer cannot be resolved MoultonAlainaProject1.java /TEST/src line 83 Java Problem
The method printIn(String) is undefined for the type PrintStream MoultonAlainaProject1.java /TEST/src line 69 Java Problem
integer cannot be resolved MoultonAlainaProject1.java /TEST/src line 33 Java Problem
JOption cannot be resolved MoultonAlainaProject1.java /TEST/src line 30 Java Problem
Syntax error, insert "}" to complete MethodBody MoultonAlainaProject1.java /TEST/src line 124 Java Problem
Syntax error on token(s), misplaced construct(s) MoultonAlainaProject1.java /TEST/src line 122 Java Problem
exit cannot be resolved or is not a field MoultonAlainaProject1.java /TEST/src line 122 Java Problem
Syntax error on token(s), misplaced construct(s) MoultonAlainaProject1.java /TEST/src line 120 Java Problem
Type mismatch: cannot convert from String to char MoultonAlainaProject1.java /TEST/src line 113 Java Problem
Syntax error, insert "}" to complete ClassBody MoultonAlainaProject1.java /TEST/src line 9 Java Problem
Scanner cannot be resolved to a type MoultonAlainaProject1.java /TEST/src line 23 Java Problem
string cannot be resolved to a type MoultonAlainaProject1.java /TEST/src line 12 Java Problem
integer cannot be resolved MoultonAlainaProject1.java /TEST/src line 28 Java Problem
Scanner cannot be resolved to a type MoultonAlainaProject1.java /TEST/src line 23 Java Problem
答案 1 :(得分：0)
JOptionPane.showMessageDialog(null, name+ ", you are taking " +creditHrs+ "credit hours, you should study " +studyHrs+ " hours a week to receive " +finalGrade+ " in your classes."
showMessageDialog（） - 方法未完成。你缺少一个右括号和分号。