为什么错误提示是：需要<标示符>？

Question

SphereSystem.java中：
class SphereSystem
{  double lightHeight;       //光线失高h
   double matterHeight;      //物高y
   double ridius;           //半径r
   double matterLen;       //物距l
   double imagingLen;       //像距l′
   double matterRefIndex;      //物方折射率n
   double imagingRefIndex;     //像方折射率n′
   double matterApertureAngle;     //孔径角u
   double imagingApertureAngle;      //孔径角u′
   double incidenceAngle;     //入射角I
   double reflectionAngle;    //反射角I′
   
   //实际光线的光路计算
   SphereSystem()
   {  double temp1,temp2;
      if(ridius!=0&&imagingRefIndex!=0)
      {  temp1=(matterLen-ridius)*Math.sin(matterApertureAngle)/ridius;
         incidenceAngle=Math.asin(temp1);
         temp2=matterRefIndex*temp1/imagingRefIndex;
         reflectionAngle=Math.asin(temp2);
         imagingApertureAngle=matterApertureAngle+incidenceAngle-reflectionAngle;
         imagingLen=ridius*(1+temp2/Math.sin(imagingApertureAngle));
      }
   }
}FirstAdaxial.java中：
import java.tio.*;
import java.util.*;class FirstAdaxial extends SphereSystem
{  FirstAdaxial()
   {  double temp1,temp2;
      if(ridius!=0&&imagingRefIndex!=0)
      {  incidenceAngle=(matterLen-ridius)*matterApertureAngle/ridius;
         reflectionAngle=matterRefIndex*incidenceAngle/imagingRefIndex;
         imagingApertureAngle=matterApertureAngle+incidenceAngle-reflectionAngle;
         imagingLen=ridius*(1+reflectionAngle/imagingApertureAngle);
      }
   }   System.out.println("Please input the l:");
   matterLen=Console.in.readDouble();
   System.out.println("please input the n:");
   matterRefIndex=Console.in.readDouble();
   System.out.println("Please input the n′:");
   imagingRefIndex=Console.in.readDouble();
   Sysem.out.println("Please input the r:");
   ridius=Console.in.readDouble();
   System.out.println("Please input the u:");
   matterApertureAngle=Console.in.readDouble();}编译SphereSyste.java没有错，但在编译FirstAdaxial.java中有错
错误提示：
c:\1111\guangxue>javac FirstAdaxial.java
FirstAdaxial.java:15:需要<标示符>
   System.out.println("Please input the l:");
                     ^
FirstAdaxial.java:16:需要<标示符>
   matterLen=Console.in.readDouble();
            ^
……
后面还有类似的错误提示
这是为什么？我改了好几次都还是这样，
万分感谢！！

Answer 1

System.out.println("Please input the l:");
   matterLen=Console.in.readDouble();
   System.out.println("please input the n:");
   matterRefIndex=Console.in.readDouble();
   System.out.println("Please input the n′:");
   imagingRefIndex=Console.in.readDouble();
   Sysem.out.println("Please input the r:");
   ridius=Console.in.readDouble();
   System.out.println("Please input the u:");
   matterApertureAngle=Console.in.readDouble();
这一段代码没有放在一个方法里