類型 變量名稱 = 類型.valueOf(新的變量名稱);//注意這里調用對應方法的是包裝類型而不是基本類型
2017-03-31
http://www.xianlaiwan.cn/article/17317
使用隨機數做字符串
使用隨機數做字符串
2017-03-31
求解?。?!為什么我每次輸出都是有序的
請輸入要選擇課程的ID:
2
請輸入要選擇課程的ID:
3
請輸入要選擇課程的ID:
1
選擇了課程:1:數據結構
選擇了課程:3:離散數學
選擇了課程:2:C語言
請輸入要選擇課程的ID:
2
請輸入要選擇課程的ID:
3
請輸入要選擇課程的ID:
1
選擇了課程:1:數據結構
選擇了課程:3:離散數學
選擇了課程:2:C語言
2017-03-31
public void testForEach(){
System.out.println("有如下課程待選:(通過foreach訪問)");
for(Object obj:coursesToSelect){
Course cr = (Course) obj;
System.out.println("課程:"+cr.id+":"+cr.name);
}
}
System.out.println("有如下課程待選:(通過foreach訪問)");
for(Object obj:coursesToSelect){
Course cr = (Course) obj;
System.out.println("課程:"+cr.id+":"+cr.name);
}
}
2017-03-31
public void testIterator(){
Iterator it = coursesToSelect.iterator();
System.out.println("有如下課程待選:(通過迭代器訪問)");
while(it.hasNext()){
Course cr = (Course)it.next();
System.out.println("課程:"+cr.id+":"+cr.name);
}
}
Iterator it = coursesToSelect.iterator();
System.out.println("有如下課程待選:(通過迭代器訪問)");
while(it.hasNext()){
Course cr = (Course)it.next();
System.out.println("課程:"+cr.id+":"+cr.name);
}
}
2017-03-31
public void testGet(){
int size = coursesToSelect.size();
System.out.println("有如下課程待選:");
for(int i=0;i<size;i++){
Course cr=(Course)coursesToSelect.get(i);
System.out.println("課程:"+cr.id+":"+cr.name);
}
}
int size = coursesToSelect.size();
System.out.println("有如下課程待選:");
for(int i=0;i<size;i++){
Course cr=(Course)coursesToSelect.get(i);
System.out.println("課程:"+cr.id+":"+cr.name);
}
}
2017-03-31
public static void main(String[] args) {
ListTest lt=new ListTest();
lt.testAdd();
}
}
ListTest lt=new ListTest();
lt.testAdd();
}
}
2017-03-31
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:"+Temp5.id+":"+Temp5.name+Temp6.id+":"+Temp6.name);
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:"+Temp5.id+":"+Temp5.name+Temp6.id+":"+Temp6.name);
2017-03-31
Course[] course = {new Course("3","離散數學"),new Course("4","語言匯編")};
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);
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);
2017-03-31
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);
coursesToSelect.add(0, cr2);
Course Temp2 =(Course) coursesToSelect.get(0);
System.out.println("添加了課程:"+Temp2.id+":"+Temp2.name);
2017-03-31
public void testAdd(){
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 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);
2017-03-31
package immoc.com.collection;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class ListTest {
public List coursesToSelect;
public ListTest(){
this.coursesToSelect = new ArrayList();
}
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class ListTest {
public List coursesToSelect;
public ListTest(){
this.coursesToSelect = new ArrayList();
}
2017-03-31