java通过出生年月获得年龄

java怎么通过出生年月获得五个学生的年龄并计算他们的平均年龄？

public class LX_1 {
static Scanner input = new Scanner(System.in);
public static void main(String[] args) {
double average,sum=0;
int x,y,z,a,b,c;
double[] ages = new double[5];
for(int i=0;i<5;i++) {
System.out.print("依次输入第"+(i+1)+"个同学的出生年月日：");
x=input.nextInt();
y=input.nextInt();
z=input.nextInt();

        System.out.print("依次输入第"+(i+1)+"个同学现在的年月日：");
        a=input.nextInt();
        b=input.nextInt();
        c=input.nextInt();
        
        ages[i] = age(x,y,z,a,b,c);
    }
    for(int i=0;i<5;i++) {
        System.out.println("第"+i+"位同学的年龄为："+ages[i]);
        sum += ages[i];
    }
    System.out.println("这五位同学的平均年龄为：" + (sum/5.0));
    
    
}

public static double age(int x,int y,int z,int a,int b,int c) {
    int year=0,month=0,day = 0;
    double age;
    
    if(a>=x){
        if(b>=y){
            if(c>=z){
                year=a-x;month=b-y;day=c-z;
            }
            else{
                year=a-x;month=b-y-1;
                if(b==4 || b==6 || b==9 || b==10){
                    day=30-z+c;
                }
                else if(b==2){
                    day=28-z+c;
                }
                else
                    day=31-z+c;
            }
        }
        else{
            if(c>=z){
                year=a-x;month=12-y+b;day=c-z;
            }
            else{
                year=a-x;month=12-y+b-1;
                if(b==4 || b==6 || b==9 || b==10){
                    day=30-z+c;
                }
                else if(b==2){
                    day=28-z+c;
                }
                else
                    day=31-z+c;
            }
        }        
    }
    
    age = year + month/12.0 + day/30.0;
    
    return age;
}

}