如何将numberGrade的值四舍五入,使得89.5变为90。numberGrade是以double类型输入的,但转换成int类型无法进行四舍五入。
public class GradeReporter
{
// The limit is the inclusive lower limit for each letter
// grade -- this means that 89.5 is an 'A' not a 'B'
public static final double A_LIMIT = 90;
public static final double B_LIMIT = 80;
public static final double C_LIMIT = 70;
public static final double D_LIMIT = 60;
public static final double F_LIMIT = 60;
/** Converts a numeric grade into a letter grade. Grades should be rounded to
* nearest whole number
*
* @param a numeric grade in the range of 0 to 100
* @returns a letter grade based on the numeric grade, possible grades are A, B, C, D and F.
*/
public char letterGrade(double numberGrade)
{
int grade = int(numberGrade);
if (grade >= A_LIMIT)
letterGrade = 'A';
else if (grade >= B_LIMIT)
letterGrade = 'B';
else if (grade >= C_LIMIT)
letterGrade = 'C';
else if (grade >= D_LIMIT)
letterGrade = 'D';
else if (grade < F_LIMIT)//4
letterGrade = 'F';
return letterGrade;
}