怎么不对，，，显示很多错误

import java.util.ArrayList;

import java.util.List;

public class ListTest {

public List coursesToSelect;

public ListTest(){

this.coursesToSelect=new ArrayList();

public void testAdd(){

//创建一个课程对象，并通过调用add方法，添加到备选课程List中

Course cr1=new Course("1","数据结构");

coursesToSelect.add(cr1);

Course temp=(Course)courseToSelect.get(0);

System.out.println("添加了课程"+temp.id+":"+temp.name);

}

public static void main(String[] args) {

ListTest It =new ListTest();

It.testAdd();

}

}