我有以下功能:
void getdata(int arr[], int n)
{
for (int i = 0; i < n; i++)
{
int a = srand(time(NULL));
arr[i] = a;
}
}
我称之为main:
getdata(arr, 1024);
我得到"空虚值不被忽视,因为它应该是"但我不明白什么是错的.为什么我会得到这个错误？
String name = request.getParameter("type");
String queryString = "SELECT * FROM Customer WHERE TYPE='Provider';";
rs = statement.executeQuery(queryString);
while(rs.next()) out.print(rs.getString(2));
没有打印,为什么？我检查了数据库连接,但我已成功连接到它.可能是什么问题？
jsp中的整个代码.我认为整个代码存在问题.这里有什么问题？
<%@page import="java.sql.Statement"%>
<%@page import="java.sql.ResultSet"%>
<%@page import="java.sql.DriverManager"%>
<%@page import="java.sql.Connection"%>
<head>
<meta charset="utf-8">
<title>GET CUSTOMER LIST</title><meta name="keywords" content="contact, direction,"><meta name="description" content="">
<meta name="HandheldFriendly" content="True">
<meta name="MobileOptimized" content="320">
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">
<meta name="format-detection" content="telephone=no">
<meta name="format-detection" content="address=no">
<link rel="canonical" href="#">
<link rel="apple-touch-icon-precomposed" sizes="114x114" href="http://www.onbile.com/nbproject/private/sushi/media/icon/apple-touch-icon.png">
<link rel="apple-touch-icon-precomposed" sizes="72x72" href="http://www.onbile.com/nbproject/private/sushi/media/icon/apple-touch-icon.png">
<link rel="apple-touch-icon-precomposed" href="http://www.onbile.com/nbproject/private/sushi/media/icon/apple-touch-icon-precomposed.png">
<link rel="shortcut icon" href="http://www.onbile.com/nbproject/private/sushi/media/icon/apple-touch-icon.png">
<!-- Mobile IE ows us …运算符重载有点问题.我有两节课.
#include <iostream>
using namespace std;
class Meter; //Forward declaration
class Inch{
private:
double inches;
public:
Inch() : inches(0) {}
Inch(double i) { inches=i; }
friend Inch operator+ (const Meter& m, const Inch& i);
void out(){ cout << "Inch:" << inches << "\n"; }
double getInches() const { return inches; }
};
和
class Meter{
private:
double meter;
public:
Meter() : meter(0) {}
Meter(double m) { meter=m; }
Meter operator+ (const Inch& i) { return Meter(meter + i.getInches() * 0.0254); …