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我正在JSP和Java（servlet）中創建一個簡單的Maven Web應用程序。我的webapp的功能是通過數據庫搜索註冊的人。它搜索ID或名稱。所以我有一個帶有表單的JSP，將數據發送到我的servlet，而在servlet中，我調用了一個Java類中的函數，它可以建立數據庫連接並獲取數據。從servlet調用Java函數，函數將不會執行
但我提到該函數從來沒有調用或別的東西，我不知道如何。任何人都可以幫忙嗎？
web.xml：
<!DOCTYPE web-app PUBLIC
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd" >
<web-app>
<display-name>Archetype Created Web Application</display-name>
<servlet>
<servlet-name>TestServlet</servlet-name>
<display-name>TestServlet</display-name>
<description></description>
<servlet-class>mvnproject.servlet.TestServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>TestServlet</servlet-name>
<url-pattern>/TestServlet</url-pattern>
</servlet-mapping>
</web-app>
JSP：
<?xml version="1.0" encoding="ISO-8859-1" ?>
<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="2.0">
<jsp:directive.page contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1" session="false"/>
<jsp:output doctype-root-element="html"
doctype-public="-//W3C//DTD XHTML 1.0 Transitional//EN"
doctype-system="http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"
omit-xml-declaration="true" />
<jsp:directive.page import="mvnproject.*" />
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Serch</title>
</head>
<body>
<h1>Zoek Persoon</h1>
<form action="TestServlet" method="POST">
<select name="serchOn">
<option value="ID" name="ID">ID</option>
<option value="name" name="name">name</option>
</select>
<input type="text" name="input"></input>
<input type="submit" placeholder="Serch"></input>
</form>
</body>
</html>
</jsp:root>
的Servlet：
package mvnproject.servlet;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.catalina.connector.Request;
/**
* Servlet implementation class TestServlet
*/
public class TestServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public TestServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
response.getWriter().append("Served at: ").append(request.getContextPath());
Functions f = new Functions();
String name = request.getParameter("serchOn");
String input = request.getParameter("input");
System.out.println(" " + name + " " + input);
System.out.println("calling db conn function");
f.dbConn(name, input);
System.out.println("Script completed");
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
}
}
Java函數：
import java.sql.*;
public class Functions {
public void dbConn(String nVal, String inpVal){
System.out.println("Running function...");
if(nVal != null || inpVal != null){
String sqlSerch;
if(nVal.equals("name")){
sqlSerch = "ID, aNaam FROM profiles WHERE naam = " + nVal;
}else{
sqlSerch = "naam, aNaam FROM profiles WHERE ID = " + nVal;
}
//driver/db path
final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
final String DB_URL = "jdbc:mysql://localhost/profile";
//DB user&password
final String USER = "root";
final String PASS = "Ciber2015!";
//declare con & sql var
Connection conn = null;
Statement stmt = null;
//register jdbc driver
try{
Class.forName(JDBC_DRIVER);
//make a connection
conn = DriverManager.getConnection(DB_URL,USER,PASS);
//SQL Statement
stmt = conn.createStatement();
String sql = "SELECT"+ sqlSerch;
ResultSet rs = stmt.executeQuery(sql);
//Declareer variablen met data uit db
int id = rs.getInt("id");
String naam = rs.getString("naam");
System.out.println(id + naam);
}catch(Exception e){
System.out.println("Eception");
}
System.out.println(" - " + nVal + " - " + inpVal);
}
}
請告訴我，如果我做錯了什麼。
完整的servlet代碼包括web.xml代碼片段？ –
請檢查這個！您的表單操作必須映射到servlet在den web.xml中註冊的url-pattern http://stackoverflow.com/questions/23751965/how-to-map-a-servlet-call-from-a-jsp -page-using-form-action – swinkler
我是否理解你在控制檯中看到「調用db conn函數」和「腳本完成」消息，但沒有「正在運行的函數...」？ –