checkin_list.jsp:
<%@ page language="java" contentType="text/html; charset=utf-8"%>
<%@ page language="java"
import="java.sql.*,java.util.*,javabean.CheckInList"%>
<html>
<head>
<title>入住记录</title>
</head>
<body>
<table width="100%" border="1" align="center" cellpadding="3"
cellspacing="1" bordercolor="00FFFF" style="border-collapse: collapse">
<tr>
<td width="30" align="center" bgcolor="CCFFFF">序号</td>
<td bgcolor='#CCFFFF'>编号</td>
<td bgcolor='#CCFFFF'>类型</td>
<td bgcolor='#CCFFFF'>大小</td>
<td bgcolor='#CCFFFF'>价格</td>
<td bgcolor='#CCFFFF'>姓名</td>
<td bgcolor='#CCFFFF'>身份证</td>
<td bgcolor='#CCFFFF'>预住天数</td>
<td bgcolor='#CCFFFF'>应付金额</td>
<td bgcolor='#CCFFFF'>压金</td>
<td bgcolor='#CCFFFF' width='80' align='center'>是否退房</td>
<td width="138" align="center" bgcolor="CCFFFF">添加时间</td>
</tr>
<%
String sql = "select * from checkin";
CheckInList cil = new CheckInList();
List list = cil.excuteSql(sql);
for(int i=0;i<list.size();i++){
CheckInList c=(CheckInList)list.get(i);
int checkin_id = c.getCheckin_id();
String room_number = c.getRoom_number();
String room_type = c.getRoom_type();
String room_size = c.getRoom_size();
String room_price = c.getRoom_price();
String customer_name = c.getCustomer_name();
String customer_id_card = c.getCustomer_id_card();
String days_to_stay = c.getDays_to_stay();
String amount_payable = c.getAmount_payable();
String deposit = c.getDeposit();
String ischeckout = c.getIscheckout();
String checkin_addedtime = c.getCheckin_addedtime();
%>
<tr>
<td width="30" align="center"><%=i%></td>
<td><%=room_number%></td>
<td><%=room_type%></td>
<td><%=room_size%></td>
<td><%=room_price%></td>
<td><%=customer_name%></td>
<td><%=customer_id_card%></td>
<td><%=days_to_stay%></td>
<td><%=amount_payable%></td>
<td><%=deposit%></td>
<td width='80' align='center'><%=ischeckout%></td>
<td width="138" align="center"><%=checkin_addedtime%></td>
</tr>
<%
//while的括号
}
%>
</table>
</body>
</html>
CheckInList.java:
package javabean;
import java.sql.*;
import java.util.*;
import db.DBUtil;
public class CheckInList {
private int checkin_id;
private String room_number;
private String room_type;
private String room_size;
private String room_price;
private String customer_name;
private String customer_id_card;
private String days_to_stay;
private String amount_payable;
private String deposit;
private String ischeckout;
private String checkin_addedtime;
private Connection conn;
private Statement stmt;
private ResultSet rs;
private List list;
private CheckInList cil;
public List excuteSql(String sql) {
conn = DBUtil.getConnection();
try {
stmt = conn.createStatement();
rs = stmt.executeQuery(sql);
while (rs.next()) {
cil=new CheckInList();
cil.setCheckin_id( rs.getInt("checkin_id"));
cil.setRoom_number(rs.getString("room_number"));
cil.setRoom_type(rs.getString("room_type"));
cil.setRoom_size(rs.getString("room_size"));
cil.setRoom_price(rs.getString("room_price"));
cil.setCustomer_name(rs.getString("customer_name"));
cil.setCustomer_id_card(rs.getString("customer_id_card"));
cil.setDays_to_stay(rs.getString("days_to_stay"));
cil.setAmount_payable(rs.getString("amount_payable"));
cil.setDeposit(rs.getString("deposit"));
cil.setIscheckout(rs.getString("ischeckout"));
cil.setCheckin_addedtime( rs.getString("checkin_addedtime"));
list.add(cil);
}
} catch (SQLException e) {
e.printStackTrace();
}
return list;
}
public int getCheckin_id() {
return checkin_id;
}
public void setCheckin_id(int checkin_id) {
this.checkin_id = checkin_id;
}
public String getRoom_number() {
return room_number;
}
public void setRoom_number(String room_number) {
this.room_number = room_number;
}
public String getRoom_type() {
return room_type;
}
public void setRoom_type(String room_type) {
this.room_type = room_type;
}
public String getRoom_size() {
return room_size;
}
public void setRoom_size(String room_size) {
this.room_size = room_size;
}
public String getRoom_price() {
return room_price;
}
public void setRoom_price(String room_price) {
this.room_price = room_price;
}
public String getCustomer_name() {
return customer_name;
}
public void setCustomer_name(String customer_name) {
this.customer_name = customer_name;
}
public String getCustomer_id_card() {
return customer_id_card;
}
public void setCustomer_id_card(String customer_id_card) {
this.customer_id_card = customer_id_card;
}
public String getDays_to_stay() {
return days_to_stay;
}
public void setDays_to_stay(String days_to_stay) {
this.days_to_stay = days_to_stay;
}
public String getAmount_payable() {
return amount_payable;
}
public void setAmount_payable(String amount_payable) {
this.amount_payable = amount_payable;
}
public String getDeposit() {
return deposit;
}
public void setDeposit(String deposit) {
this.deposit = deposit;
}
public String getIscheckout() {
return ischeckout;
}
public void setIscheckout(String ischeckout) {
this.ischeckout = ischeckout;
}
public String getCheckin_addedtime() {
return checkin_addedtime;
}
public void setCheckin_addedtime(String checkin_addedtime) {
this.checkin_addedtime = checkin_addedtime;
}
}
异常信息：
严重: Servlet.service() for servlet [jsp] in context with path [/test] threw exception [An exception occurred processing JSP page /checkin_list.jsp at line 29
26: <%
27: String sql = "select * from checkin";
28: CheckInList cil = new CheckInList();
29: List list = cil.excuteSql(sql);
30: for(int i=0;i<list.size();i++){
31: CheckInList c=(CheckInList)list.get(i);
32: int checkin_id = c.getCheckin_id();
Stacktrace:] with root cause
java.lang.NullPointerException
at javabean.CheckInList.excuteSql(CheckInList.java:48)
