package com.imooc.collection;import java.util.ArrayList;import java.util.List;/*?*??* ?備選課程類?*/public class ListTest { public List coursesToSelect; /* *? * 用于存放備選課程的List */ public ListTest(){ this.coursesToSelect = new ArrayList(); } /* *? * 用于往 coursesToSelect 中添加備選課程 */ public void testAdd(){ //創(chuàng)建一個課程對象,并通過調(diào)用add方法,添加到備選課程中 Course cr1 = new Course("1","數(shù)據(jù)結(jié)構(gòu)"); 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); // 以下方法會拋出數(shù)組下標越界異常// Course cr3 = new Course("3","test");// coursesToSelect.add(4,cr3); // 以下為出現(xiàn)錯誤,自己不會調(diào)試過來,"沒有Arrays類" Course[] course = {new Course("3","離散數(shù)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); // 同上問題,百度說是引入包不正常,但是已經(jīng)引入了ArrayList包。 Course[] course2 = {new Course("5","高等數(shù)學"),new Course("6","匯編語言")}; coursesToSelect.addAll(2,Arrays.asLst(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); } public void testGet(){ int size = coursesToSelect.size(); for(int i=0; i<size;i++){ Course cr = (Course) coursesToSelect.get(i); System.out.println("課程"+cr.id+":"+cr.name); } } public static void main( String[] args){ ListTest lt =new ListTest(); lt.testAdd(); lt.testGet(); }}
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TA貢獻3條經(jīng)驗 獲得超4個贊
哎,還是我自己解決了問題,解決辦法是更換jdk版本,jdk1.8版本是最新版,不太穩(wěn)定所以出現(xiàn)這種狀況。有遇到同一問題的童鞋來找我。
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