package?test3.collection;
import?java.util.ArrayList;
import?java.util.Arrays;
import?java.util.List;
import?java.util.Scanner;
public?class?SetTest?{
?public?List<Course>coursesToSelect;
?
?public?SetTest(){
??coursesToSelect=new?ArrayList<Course>();
?}
?
?public?void?testAdd(){
?????//創建一個課程對象，并通過調用add方法，添加到備選課程List中
?????Course?cr1=new?Course("1:","數據結構");
?????coursesToSelect.add(cr1);
?????Course?temp=(Course)coursesToSelect.get(0);
//?????System.out.println("添加了課程："+temp.id+temp.name);
?????
?????Course?cr2=new?Course("2:","C語言");
?????coursesToSelect.add(0,?cr2);
?????Course?temp2=(Course)coursesToSelect.get(0);
//?????System.out.println("添加了課程："+temp2.id+temp2.name);
?????
?????Course[]?course={new?Course("3","離散數學"),new?Course("4","匯編語言")};
?????coursesToSelect.addAll(Arrays.asList(course));
?????Course?temp3=(Course)coursesToSelect.get(2);
?????Course?temp4=(Course)coursesToSelect.get(3);
//?????System.out.println("添加了兩門課程："+temp3.id+':'+temp3.name+';'
//???????+temp4.id+':'+temp4.name);
?????Course[]?course2={new?Course("5","高等數學"),new?Course("6","大學英語")};
?????coursesToSelect.addAll(2,Arrays.asList(course2));
?????Course?temp5=(Course)coursesToSelect.get(2);
?????Course?temp6=(Course)coursesToSelect.get(3);
//?????System.out.println("添加了兩門課程："+temp5.id+':'+temp5.name+';'
//???????+temp6.id+':'+temp6.name);
?????
?????/*Course?cr3=new?Course("2:","C語言");
?????coursesToSelect.add(6,?cr3);
?????Course?temp7=(Course)coursesToSelect.get(6);
?????System.out.println("添加了課程："+temp7.id+temp7.name);
?????*/
????}
?/*
?????*?通過for?each方法訪問集合元素
?????*/
????public?void?testForEach(){
?????System.out.println("有如下課程待選：(for?each訪問)");
?????for(Object?obj:coursesToSelect){
??????Course?cr=(Course)obj;
??????System.out.println("課程："+cr.id+cr.name);
?????}
????}
????
????public?static?void?main(String[]?args)?{
??
?????SetTest?st=new?SetTest();
?????st.testAdd();
?????st.testForEach();
?????//創建一個學生對象
?????Student?student=new?Student("1","小明");
?????System.out.println("歡迎學生："+student.name+"選課!");
?????//創建一個Scanner對象，用來接收從鍵盤輸入的課程ID
?????Scanner?console=new?Scanner(System.in);
?????
?????for(int?i=0;i<3;i++){
??????System.out.println("請輸入課程ID");
??????String?courseId=console.next();
??????for(Course?cr:st.coursesToSelect){
???????if(cr.id.equals(courseId)){
??????student.courses.add(cr);??
???????}
??????}
?????}
?????
??????st.testForEachForSet(student);
?}
?????public?void?testForEachForSet(Student?student){
?????//打印輸出，學生所選的課程！
??????for(Course?cr:student.courses){
??????System.out.println("選擇了課程："+cr.id+":"+cr.name);
?????}
????}
}

?已解決?。。?！謝謝