java - 在restful web服务中访问mysql jdbc驱动程序

Question

我有一个非常简单的 Restful 网络服务，我想在其中访问数据库中的数据。不幸的是我总是遇到这个异常:

SCHWERWIEGEND: Servlet.service() for servlet [Jersey REST Service] in context with path [/test_projects] threw exception [org.glassfish.jersey.server.ContainerException: java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost/test_projects] with root cause java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost/test_projects

我的 Web 服务中的资源类如下所示。

package ws;

import java.sql.SQLException;

import javax.ws.rs.Path;
import javax.ws.rs.GET;
import javax.ws.rs.Produces;

import model.Person;

import com.google.gson.Gson;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

@Path("/persons")
public class PersonsResource {

    static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
    static final String DB_URL = "jdbc:mysql://localhost/zhaw_projects";

    static final String USER = "root";
    static final String PASS = "";

    @GET
    // produce json
    @Produces("application/json")
    public String getPersonJSON() throws SQLException {

        // build connection
        Connection connection = DriverManager.getConnection(DB_URL, USER, PASS);

        // create statement
        Statement statement = connection.createStatement();

        // select query
        String personsQuery = "SELECT * FROM persons";

        // execute query
        ResultSet rs = statement.executeQuery(personsQuery);

        // a list of persons
        List<Person> persons = new ArrayList<Person>();

        // add persons
        while (rs.next()) {

            persons.add(new Person(rs.getInt("personID"), rs
                    .getString("firstName"), rs.getString("lastName"), rs
                    .getString("token"), rs.getString("email")));
        }

        // new json string with the persons list
        Gson gson = new Gson();
        String jsonString = gson.toJson(persons);

        return jsonString;
    }
}

我的 web.xml 看起来像这样:

<?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">
  <servlet>
    <servlet-name>Jersey REST Service</servlet-name>
    <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
    <init-param>
      <param-name>jersey.config.server.provider.packages</param-name>
      <param-value>ws</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>Jersey REST Service</servlet-name>
    <url-pattern>/rest/*</url-pattern>
  </servlet-mapping>
</web-app>

我使用 apache tomcat 作为 Web 服务器。我的 JDBC 驱动程序当前位于 WebContent/WEB_INF/lib 目录中。我需要将 jdbc 驱动程序放在哪里才能使其工作？

Answer 1

我明白了。我不得不把

Class.forName(JDBC_DRIVER);

到我的代码。