编写一个子程序计算矩形的面积，在主程序中由键盘输入两个数为矩形的两个边厂，调用子程序计算矩形的面积

package t;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class test {

public Long cal1( Integer x,Integer y) {

return new Long(x*y);
}
public static void main(java.lang.String[] args) throws NumberFormatException, IOException {

System.out.println("请输入第一个数字：");
BufferedReader reader = new BufferedReader(new InputStreamReader(
System.in));
Integer i = Integer.parseInt(reader.readLine());
System.out.println("请输入第二个数字：");
Integer j = Integer.parseInt(reader.readLine());
test t = new test();
Long l = t.cal1(i,j);

System.out.println("面积是：" + l);
}
}