student.courses.size() 怎么理解,這里student應(yīng)該不是對(duì)象吧,靜態(tài)方法下才要用對(duì)象引用
public void testForEachiForSet(Student student){
//打印輸出,學(xué)生所選的課程
System.out.println("共選擇了"+student.courses.size()+"門課程");
for (Course ?cr : student.courses) {
System.out.println("選擇了課程:"+cr.id+":"+cr.name);
2017-01-24
表示學(xué)生中課程集合的長度
2017-01-13
這是testForEachiForSet()的參數(shù)~,這個(gè)方法的參數(shù)就是一個(gè)Student類型的引用,輸出的就是其參數(shù)即student的id和name呀
2017-01-13
public?static?void?main(String[]?args)?{ SetTest?st?=new?SetTest(); st.testAdd(); st.testForEach(); //創(chuàng)建一個(gè)新的學(xué)生對(duì)象 Student?student=?new?Student("1","小明"); System.out.println("歡迎學(xué)生:"+studnet.name+"選課"); //創(chuàng)建一個(gè)Scanner?對(duì)象,來接受鍵盤輸入的課程 id; Scanner?console?=?new?Scanner(System.in); for(int?i=0;i<3;i++){ System.out.println("請(qǐng)輸入ID"); String?courseId?=?console.next(); for?(Course?cr?:st.coursesToSelect){ if(cr.id.equals(courseId)){ student.courses.add(cr); //student.courses.add(cr); } } } st.testForEachiForSet(student); } public?void?testForEachiForSet(Student?student){ //打印輸出,學(xué)生所選的課程 System.out.println("共選擇了"+student.courses.size()+"門課程"); for?(Course??cr?:?student.courses)?{ System.out.println("選擇了課程:"+cr.id+":"+cr.name); } } }2017-01-13
public static void main(String[] args) {
SetTest st =new SetTest();
st.testAdd();
st.testForEach();
//創(chuàng)建一個(gè)新的學(xué)生對(duì)象
Student aa = new Student("1","小明");
System.out.println("歡迎學(xué)生:"+aa.name+"選課");
//創(chuàng)建一個(gè)Scanner 對(duì)象,來接受鍵盤輸入的課程 id;
Scanner console = new Scanner(System.in);
for(int i=0;i<3;i++){
System.out.println("請(qǐng)輸入ID");
String courseId = console.next();
for (Course cr :st.coursesToSelect){
if(cr.id.equals(courseId)){
aa.courses.add(cr);
//student.courses.add(cr);
}
}
}
st.testForEachiForSet(aa);
}
public void testForEachiForSet(Student student){
//打印輸出,學(xué)生所選的課程
System.out.println("共選擇了"+student.courses.size()+"門課程");
for (Course ?cr : student.courses) {
System.out.println("選擇了課程:"+cr.id+":"+cr.name);
}
}
}
2017-01-13
testForEachiForSet(Student student) ??student.courses.size()中 ?student是一個(gè)Student