java如何从restful web服务中获取一些数据，并将其保存到数据库中？

Question

我已经编写了一些代码，利用SOAPUI作为用户界面，通过RESTfulWeb服务将一些数据保存到数据库中。我用@put来做这个。以下是运行的步骤：

1-在Tomcat 9.0服务器上运行代码。 2-使用SOAPUI中的URL放置一些数据

但当我在SOAPUI中使用PUT时，给出first和last的字符串值并运行它，这些值不会添加到我的数据库中。Hoewer，json文件得到了正确的值

{
   "first": "Jon",
   "last": "Snow"
}

以下是我的代码的重要部分：

package tomcat.rest.eclipse.database;

public class Score {

    public static String first, last;
}

public class ScoreService {
@PUT
    @Path("/score")
    @Produces("application/json")
    public String update(@QueryParam("first") String first, 
                             @QueryParam("last") String last) {
                    Score.first = first;
                    Score.last = last;

                    final String var1 = Score.first;
                    final String var2 = Score.last;
                    database.insert(var1, var2);

                    String pattern = "{ \"first\":\"%s\", \"last\":\"%s\"}";
                    return String.format(pattern, Score.first, Score.last);
    }
}

这是我的连接：

public class database {

public static Connection getConnection() {

            try {
                String driver = "com.mysql.jdbc.Driver";
                String url = "jdbc:mysql://localhost:3306/testdb";
                String username = "root";
                String password = "00000";
                Class.forName(driver);
                Connection conn = DriverManager.getConnection(url, username, password);
                System.out.println("Connected");
                return conn;
            } catch(Exception e) {System.out.println(e);}

            return null;    
            }

public static void insert(final String var1, final String var2) {

        try {
            Connection con = getConnection();
            PreparedStatement posted = con.prepareStatement("INSERT INTO student (first, last) VALUES ('"+var1+"', '"+var2+"')");
            posted.executeUpdate();
        } catch(Exception e) {System.out.println(e);}
        finally {
            System.out.println("Insert completed");
        }
    }
}

控制台上的输出为：

java.lang.ClassNotFoundException: com.mysql.jdbc.Driver java.lang.ClassNotFoundException: com.mysql.jdbc.Driver java.lang.NullPointerException Insert completed

如何将web服务正确连接到数据库以在数据库中保存一些记录？非常感谢你帮助我

Answer 1

只需下载mysql connectorjar并将其添加到项目构建路径中

或

Add the jar file to your WEB-INF/lib folder. Right-click your project in Eclipse, and go to "Build Path > Configure Build Path" Add the "Web App Libraries" library This will ensure all WEB-INF/lib jars are included on the classpath.

或者使用maven时使用jdbc mysql maven依赖项：

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.6</version>
</dependency>

Edit: right click on your project => Build Path => Configure Build Path => tab "Libraries" and you click on "Add External JARs" and you point to your file "mysql-connector-java-5.1.17-bin.jar"

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.EmptyStackException;

public class SingletonConnection   {


    private static Connection connection = null ;
    static 
    {
        try{
            Class.forName("com.mysql.jdbc.Driver");
            connection = DriverManager.getConnection
                    ("jdbc:mysql://localhost:3306/dbnameX","root","");
        }catch(Exception ex)
        {

        }

    }
    public static Connection getConnection() throws Exception {
        return connection;
    }


}