public class Course { public String id; public String name; public Course(String id,String name){ this.id=id; this.name=name; }}import java.util.HashSet;import java.util.Set;public class Student { public String id; public String name; public Set courses; public Student(String id,String name){ this.id=id; this.name=name; this.courses=new HashSet(); }}import java.util.ArrayList;import java.util.List;public class TestAdd { public List courseAll; public TestAdd(){ this.courseAll=new ArrayList(); } public void Add(){ Course cr1=new Course("1","数据结构"); courseAll.add(cr1); Course cr2=new Course("2","C语言"); courseAll.add(1, cr2); courseAll.add(new Course("3","数学")); courseAll.add(new Course("4","语文")); } public void use(){ TestAdd it=new TestAdd(); it.Add(); for(Course cr:it.courseAll){ System.out.println("id: "+cr.id+" name: "+cr.name); } }}public class Main { public static void main(String[] args) { TestAdd add=new TestAdd(); add.Add(); add.use(); }} |