package com.imooc.collection;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
/*
* 被选课程类
*/
public class ListTest {
/*
* 用于存放被选课程的List
*/
public List coursesToSelect;
public ListTest(){
this.coursesToSelect=new ArrayList();
}
/*
*用于往courseToSelect中添加被选课程
*/
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)coursesToSelect.get(0);
System.out.println("添加了课程:"+temp.id+":"+temp.name);
Course cr2=new Course("2","C语言");
coursesToSelect.add(0, cr2);
Course temp2=(Course)coursesToSelect.get(0);
System.out.println("添加了课程:"+temp2.id+":"+temp2.name);
coursesToSelect.add(cr1);
Course temp0=(Course)coursesToSelect.get(2);
System.out.println("添加了课程:"+temp0.id+":"+temp0.name);
//以下方法会抛出数组下标越界异常
//Course cr3=new Course("1","sfsa");
//coursesToSelect.add(4, cr3);
/*
* 以下是两个addAll方法
*/
Course course[]={new Course("3","离散数学"),new Course("4","汇编语言")};
coursesToSelect.addAll(Arrays.asList(course));
Course temp3=(Course)coursesToSelect.get(3);
Course temp4=(Course)coursesToSelect.get(4);
System.out.println("添加了两门课程:"+temp3.id+":"+temp3.name+";"+temp4.id+":"+temp4.name);
Course course2[]={new Course("5","高等数学"),new Course("6","大学英语")};
coursesToSelect.addAll(2, Arrays.asList(course2));
Course temp5=(Course) coursesToSelect.get(2);
Course temp6=(Course) coursesToSelect.get(3);
System.out.println("添加了两门课程:"+temp5.id+":"+temp5.name+";"+temp6.id+":"+temp6.name);
}
/*
* 取得List中的方法
*/
public void testGet(){
int size=coursesToSelect.size();
System.out.println("有如下课程待选:");
for(int i=0;i<size;i++){
Course cr=(Course) coursesToSelect.get(i);
System.out.println("课程:"+cr.id+":"+cr.name);
}
}
/*
* 通过迭代器来遍历list
*/
public void testIterator(){
//通过集合的iterator方法,取得迭代器的实例
Iterator it = coursesToSelect.iterator();
System.out.println("有如下课程待选(通过迭代器访问):");
while (it.hasNext()){
Course cr=(Course) it.next();
System.out.println("课程:"+cr.id+":"+cr.name);
}
}
/*
* 通过for each方法访问集合元素
*/
public void testForEach(){
System.out.println("有如下课程待选(通过for each器访问):");
for(Object obj:coursesToSelect){
Course cr=(Course)obj;
System.out.println("课程:"+cr.id+":"+cr.name);
}
}
/*
* 修改list中的元素
*/
public void testModify(){
coursesToSelect.set(4, new Course("7","毛概"));
}
/*
* 删除list中的元素
*/
public void testRemove(){
//Course cr=(Course) coursesToSelect.get(4);
System.out.println("即将删除4位置和5位置的课程");
Course courses[]={(Course) coursesToSelect.get(4),(Course) coursesToSelect.get(5)};
coursesToSelect.removeAll(Arrays.asList(courses));
//coursesToSelect.remove(4);
System.out.println("成功删除课程!");
testForEach();
}
/*
*
*/
public static void main(String args[]){
ListTest lt= new ListTest();
lt.testAdd();
lt.testGet();
lt.testIterator();
lt.testForEach();
lt.testModify();
lt.testForEach();
lt.testRemove();
}
}