Java使用枚举来消除if else（转载）

public enum Grade {

A_10_90(90, 100, "A"), B_90_80(80, 90, "B"), C_80_60(60, 80, "C"), D_60_0(0, 60, "D"), OTHER(-1, -1, "E");



private int start;

private int end;

private String grade;



Grade(int start, int end, String grade) {

    this.setStart(start);

    this.setEnd(end);

    this.setGrade(grade);

}



public int getStart() {

    return start;

}



public void setStart(int start) {

    this.start = start;

}



public int getEnd() {

    return end;

}



public void setEnd(int end) {

    this.end = end;

}



public String getGrade() {

    return grade;

}



public void setGrade(String grade) {

    this.grade = grade;

}



public static String getGrade(int score) {

    for (Grade grade : values()) {

        if (grade.getStart() <= score && score < grade.getEnd()) {

            return grade.getGrade();

        }

    }

    return OTHER.getGrade();

}

public class GradeTest {

@Test

public void test() {

    System.out.println(Grade.getGrade(78));

}

}