Java 在eclipse中使用servlet和jsp将数据插入数据库
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insert data into database using servlet and jsp in eclipse
提问by Atiq
I am trying to add or insert values into table of database using servlet and jsp and MySQL Workbench as database. These are the following details:
我正在尝试使用 servlet 和 jsp 以及 MySQL Workbench 作为数据库向数据库表中添加或插入值。这些是以下详细信息：
1.> Register.java
1.>注册.java
package register.com;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.sql.*;
import javax.servlet.*;
/**
* Servlet implementation class Register
*/
@WebServlet("/register")
public class Register extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public Register() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see Servlet#init(ServletConfig)
*/
public void init(ServletConfig config) throws ServletException {
// TODO Auto-generated method stub
}
/**
* @see HttpServlet#service(HttpServletRequest request, HttpServletResponse response)
*/
protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
response.setContentType("text/html");
PrintWriter pw = response.getWriter();
//String connectionURL = "jdbc:mysql://127.0.0.1:3306/newData";// newData is the database
//Connection connection;
Connection conn=null;
String url="jdbc:mysql://localhost:3306/";
String dbName="userlogindb";
String driver="com.mysql.jdbc.Driver";
//String dbUserName="root";
//String dbPassword="root";
try{
String Fname = request.getParameter("fname");
String Mname = request.getParameter("mname");
String Lname = request.getParameter("lname");
String Uname = request.getParameter("username");
String Emailid = request.getParameter("emailid");
String Mobno = request.getParameter("mobno");
String Address = request.getParameter("address");
String Password1 = request.getParameter("password1");
String Password2 = request.getParameter("password2");
Class.forName(driver).newInstance();
conn = DriverManager.getConnection(url+dbName,"root", "root");
PreparedStatement pst =(PreparedStatement) conn.prepareStatement("insert into 'userlogindb'.'registerutable'(fname,mname,lname,username,emailid,mobno,address,password1,password2) values(?,?,?,?,?,?,?,?,?)");//try2 is the name of the table
pst.setString(1,Fname);
pst.setString(2,Mname);
pst.setString(3,Lname);
pst.setString(4,Uname);
pst.setString(5,Emailid);
pst.setString(6,Mobno);
pst.setString(7,Address);
pst.setString(8,Password1);
pst.setString(9,Password2);
int i = pst.executeUpdate();
conn.commit();
String msg=" ";
if(i!=0){
msg="Record has been inserted";
pw.println("<font size='6' color=blue>" + msg + "</font>");
}
else{
msg="failed to insert the data";
pw.println("<font size='6' color=blue>" + msg + "</font>");
}
pst.close();
}
catch (Exception e){
pw.println(e);
}
}
}
2.> index.jsp
2.> index.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<form name="registrationform" action="register" method="post">
<p>
Enter your first name: <input type="text" name="fname"><br>
Enter your middle name: <input type="text" name="mname"><br>
Enter your last name: <input type="text" name="lname"><br>
</p><br>
<p>
Enter username: <input type="text" name="username"><br>
</p><br>
<p>
Enter email id: <input type="text" name="emailid"><br>
Enter mobile number: <input type="text" name="mobno"><br>
Enter address: <textarea rows="5" cols="5" name="address"></textarea><br>
</p><br>
<p>
Enter the password: <input type="password" name="password1"><br>
Reenter the password: <input type="password" name="password2"><br>
</p><br>
<p>
<input type="submit">
</p><br>
</form>
</body>
</html>
3.> web.xml
3.> web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>RegisterExample</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<description>Register Servlet</description>
<display-name>Register</display-name>
<servlet-name>Register</servlet-name>
<servlet-class>register.com.Register</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Register</servlet-name>
<url-pattern>/register</url-pattern>
</servlet-mapping>
</web-app>
4.> I have added mysql-connector-java-5.0.8-bin.jar and servlet-api-3.0.jaris anything else needed to add it. I have created a connection to database in Data Source Explorer.
4.>我已经添加了 mysql-connector-java-5.0.8-bin.jar 和 servlet-api-3.0.jar是添加它所需的任何其他内容。我在数据源资源管理器中创建了到数据库的连接。
When I m compiling or debuging it shows no error. During runtime also there is no error. When I fill in the form and submit it shows only blank screen :( No output is displayed. :( Also in the database values are not updated.
当我编译或调试时，它没有显示错误。在运行时也没有错误。当我填写表单并提交时，它只显示空白屏幕 :( 不显示任何输出。 :( 数据库中的值也未更新。
Please help me. I m getting hangover with this snippet.
请帮我。我对这个片段感到宿醉。
采纳答案by Kick
Check that doPost()method of servlet is called from the jsp form and remove conn.commit.
检查doPost()servlet 的方法是否从 jsp 表单中调用并删除conn.commit。
回答by Gautam Savaliya
Can you check value of iby putting logger or println(). and check with closing db conn at the end. Rest your code looks fine and it should work.
您可以i通过放置 logger 或 println() 来检查值。并在最后关闭 db conn 进行检查。休息你的代码看起来不错，它应该可以工作。
回答by ranjit
Same problem fetch main problem in PreparedStatementuse simple statement then you successfully insert record same use below.
同样的问题在PreparedStatement使用简单语句中获取主要问题 然后您成功插入下面相同使用的记录。
String st2="insert into
user(gender,name,address,telephone,fax,email,
destination,sdate,edate,Participant,hcategory,
Culture,Nature,People,Cities,Beaches,Festivals,username,password)
values('"+gender+"','"+name+"','"+address+"','"+phone+"','"+fax+"',
'"+email+"','"+desti+"','"+sdate+"','"+edate+"','"+parti+"',
'"+hotel+"','"+chk1+"','"+chk2+"','"+chk3+"','"+chk4+"',
'"+chk5+"','"+chk6+"','"+user+"','"+password+"')";
int i=stm.executeUpdate(st2);
回答by Bharat
In your JSP at line <form>tag,
try this code
在行<form>标记处的 JSP 中，试试这个代码
<form name="registrationform" action="Register" method="post">
回答by mohan
String user = request.getParameter("uname");
out.println(user);
String pass = request.getParameter("pass");
out.println(pass);
Class.forName( "com.mysql.jdbc.Driver" );
Connection conn = DriverManager.getConnection( "jdbc:mysql://localhost:3306/rental","root","root" ) ;
out.println("hello");
Statement st = conn.createStatement();
String sql = "insert into login (user,pass) values('" + user + "','" + pass + "')";
st.executeUpdate(sql);
回答by user22277
Remove conn.commit from Register.java
从 Register.java 中删除 conn.commit
In your jsp change action to :<form name="registrationform" action="Register" method="post">
在您的 jsp 更改操作中：<form name="registrationform" action="Register" method="post">
回答by Fernando
I had a similar issue and was able to resolve it by identifying which JDBC driver I intended to use. In my case, I was connecting to an Oracle database. I placed the following statement, prior to creating the connection variable.
我有一个类似的问题，并且能够通过确定我打算使用哪个 JDBC 驱动程序来解决它。就我而言，我正在连接到 Oracle 数据库。我在创建连接变量之前放置了以下语句。
DriverManager.registerDriver( new oracle.jdbc.driver.OracleDriver());
DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
