请问第五行为什么时候出错

public class Test1 {

public static void main(String[]args){
int medalall=800; //member variable
public void china(){
int medalchina=100; //local variable for the method
if(true){ //code block
int gold=50; //local variable for the code block
medalchina+=50; //to be allowed access
medalall-=150; //to be allowed access

      }
      gold=100;   //compile errors
      medal_china+=100;//to be allowed access
      medal_All-=200;  //to be allowed access
      public void(){   
          medal_All=800;//to be allowed access
          medal_china=100;//compile errors,it can't allow to local variable of other method
          gold=10;        //compile errors
      }
  }

}
}

main方法里面怎么还包含一个方法？

方法里面包方法这是什么规则