学号 姓名 籍贯
1 a Z
2 b X
3 c D
4 d X
我就是想找到一个符合的记录,找学号也行,找名字也行,找籍贯也行昨天我是把这些写成一个类,用
hashmap.put(stu.学号,stu);
Student stu2 = (Student)hashmap.get(stu.学号)
System.out.println(stu2.姓名); System.out.println(stu2.学号);
System.out.println(stu2.籍贯);
方法来查找的
现在我想写到arraylist中,结果不对,是我的arraylist用的又问题,import java.util.*;
public class UseHashMap{
public static void main(String[] args) {
/* Use of HashMap
* Begin
*/
ArrayList pArrayList=new ArrayList();
String aa= "2";
HashMap hashmap = new HashMap();
String [] p=new String[]{"1","2","3","4"};
String [] q=new String[]{"a","b","c","d"};
String [] r=new String[]{"Z","X","D","X"}; for(int i=0; i<=3;i++)
{
pArrayList.add(i,p[i],q[i],r[i]);//这里怎么添加呢
hash.put(pArrayList.indexof(0),pArrayList );//这里也不对
};
System.out.println(hashmap.get(aa));
}
}
1 a Z
2 b X
3 c D
4 d X
我就是想找到一个符合的记录,找学号也行,找名字也行,找籍贯也行昨天我是把这些写成一个类,用
hashmap.put(stu.学号,stu);
Student stu2 = (Student)hashmap.get(stu.学号)
System.out.println(stu2.姓名); System.out.println(stu2.学号);
System.out.println(stu2.籍贯);
方法来查找的
现在我想写到arraylist中,结果不对,是我的arraylist用的又问题,import java.util.*;
public class UseHashMap{
public static void main(String[] args) {
/* Use of HashMap
* Begin
*/
ArrayList pArrayList=new ArrayList();
String aa= "2";
HashMap hashmap = new HashMap();
String [] p=new String[]{"1","2","3","4"};
String [] q=new String[]{"a","b","c","d"};
String [] r=new String[]{"Z","X","D","X"}; for(int i=0; i<=3;i++)
{
pArrayList.add(i,p[i],q[i],r[i]);//这里怎么添加呢
hash.put(pArrayList.indexof(0),pArrayList );//这里也不对
};
System.out.println(hashmap.get(aa));
}
}
pArrayList.add(2, Student2)
pArrayList.add(3, Student3)