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java.lang.ClassNotFoundException:com.mysql.jdbc.Driver(jar文件已经链接并放置在WEB-INF / lib中)

[英]java.lang.ClassNotFoundException: com.mysql.jdbc.Driver (jar file already linked and placed in WEB-INF/lib)

我针对该错误找到的解决方案是“通过构建路径添加jar文件”和“将包含驱动程序的jar文件放入WEB-INF / lib中”(以及类似的提法),但是我已经尝试了这两个方法。

回到我的问题。 这是我的代码:

jsp文件

<?xml version="1.0" encoding="ISO-8859-1" ?>
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
    <%@ page import="db.DBAccess" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1" />
<title>Insert title here</title>
</head>
<body>

<jsp:useBean id="dba" class="db.DBAccess"></jsp:useBean>

<jsp:setProperty name="dba" property="selection" value="s" /> 

</body>
</html>

Javabean

package db;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class DBAccess {

    public DBAccess() {
    }

    private String selection = "";

    public void setSelection(String s) {

        final String driver = "com.mysql.jdbc.Driver";

        String url = "jdbc:mysql://localhost:3306/test";
        String user = "user1";
        String pswd = "user1pswd";

        Connection con = null;
        Statement stmt = null;

        try {
            // initialize connection
            Class.forName(driver);
            con = DriverManager.getConnection(url, user, pswd);
            stmt = con.createStatement();
            // execute select
            ResultSet results = stmt.executeQuery("SELECT * FROM t");
            results.next();
            selection =  results.getString(1);
            // close connection
            stmt.close();
            con.close();
        } catch (ClassNotFoundException cnfe) {
            System.out.println(cnfe.toString());
        } catch (SQLException e) {
            System.out.println(e.toString());
            }

    }
}

t的内容是带有标签“字符串”和内容“ hello world”的一列

即使我正确链接了jar文件,为什么仍会收到此异常?

您是否将jar文件插入到Webinf的lib文件夹中?

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