5

我已经在数据库中插入了一条记录，但我不知道如何检索它。我的代码是： Account.java：

package com.fetch;

import java.io.Serializable;
import javax.persistence.Column;
import javax.persistence.Id;

public class Account implements Serializable 
{   
  @Id
  private long id;

  @Column(name="NAME")  
  private String name;

  public Account()  
  {

  }

  public Account(int id, String name)   
  {     
     this.id = id;      
     this.name = name;  
  }

  public long getId() 
  {     
     return id; 
  }

  public void setId(long id) 
  {     
     this.id = id;  
  }

  public String getName() 
  {     
     return name;   
  }

  public void setName(String name)
  {     
     this.name = name;  
  }
}

我的帐户.java：

package com.fetch;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.Collection;
import javax.jws.WebMethod;
import javax.jws.WebService;
import javax.persistence.Entity;
import javax.persistence.NamedQuery;
import javax.persistence.Table;
import javax.ws.rs.FormParam;
import javax.ws.rs.GET;
import javax.ws.rs.POST;
import javax.ws.rs.Path;

@WebService()
@Entity
@Table(name = "CUSTOMER")
@Path("/user")
@NamedQuery(name="loginquery", query="select ID,NAME from CUSTOMER")
public class MyAccount 
{   
   private Account ac;  
   public MyAccount()   
   {    
     // TODO Auto-generated constructor stub      
     ac = new Account();    
   }    

   @POST    
   @Path("/fetch")  
   @WebMethod(operationName = "insert") 
   public String insert(@FormParam("name") String name) 
   {     
      try   
      {     
         Class.forName("com.mysql.jdbc.Driver");        
         Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/studentinfo", "root", "root");

         String query = "insert into CUSTOMER"+"(NAME) VALUES"+"(?)";
     PreparedStatement st = con.prepareStatement(query);    
         st.setString(1,name);  
     st.executeUpdate();
      }     
      catch (Exception e)   
      {     
         System.out.println(e.getMessage());    
      } 
      return"Record inserted successfully";
   }    
  public Account getAc() 
  {     
     return ac; 
  } 
  public void setAc(Account ac) 
  {     
     this.ac = ac;  
  }
}

插入.html：

<!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=UTF-8">
<title>Insert</title>
</head>
<body>
    <form action="rest/user/fetch" method="POST">
        <p>
            Name : <input id="name" name="name" />
        </p>
        <input type="submit" value="Add" />
            <input type="submit" value="Retrive" />
    </form>
</body>
</html>

网页.xml：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 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>FetchAndInsert</display-name>
   <servlet>
      <servlet-name>REST Servlet</servlet-name>
      <servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
      <init-param>
         <param-name>com.sun.jersey.config.property.packages</param-name>
         <param-value>com.fetch</param-value>
      </init-param>
      <load-on-startup>1</load-on-startup>
   </servlet>
   <servlet-mapping>
      <servlet-name>REST Servlet</servlet-name>
      <url-pattern>/rest/*</url-pattern>
   </servlet-mapping>
</web-app>

当用户单击检索按钮时，如何从数据库中检索数据，并在另一个 HTML 表单中显示所有记录？请就如何做到这一点提出建议。

在我的应用程序中，当用户单击检索按钮时，它正在执行插入操作。但我想要的是，当用户单击时，它应该转到另一个页面并显示数据库中表中的数据。

任何人都可以说出我所做的错误，并提出建议以找到解决方案以及当用户单击检索按钮时如何在其他页面中显示动态表？

4

2 回答 2

3

最后我已经完成了，现在我可以使用 jersey(JAX - RS) webservices 执行插入和检索数据库中的数据，并能够在 html 页面中显示它。

帐户.java：

package com.fetch;

import java.io.Serializable;
import javax.persistence.Column;
import javax.persistence.Id;

public class Account implements Serializable 
{
    @Id
    private long id;

    @Column(name = "NAME")
    private String name;

    public Account(int id, String name)
    {
        this.id = id;
        this.name = name;
    }
    public long getId() {
        return id;
    }
    public void setId(long id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
}

我的帐户.java：

package com.fetch;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import javax.jws.WebMethod;
import javax.jws.WebService;
import javax.persistence.Entity;
import javax.ws.rs.FormParam;
import javax.ws.rs.GET;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;

@WebService()
@Entity
@Path("/user")
public class MyAccount
{
    @POST
    @Path("/fetch")
    @WebMethod(operationName = "insert")
    public String insert(@FormParam("name") String name) 
    {
        try 
        {
            Class.forName("com.mysql.jdbc.Driver");
            Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/studentinfo", "root", "root");
            String query = "insert into CUSTOMER"+"(NAME) VALUES"+"(?)";

            PreparedStatement st = con.prepareStatement(query);
            st.setString(1,name);
            st.executeUpdate();     
        } 
        catch (Exception e) 
        {
            System.out.println(e.getMessage());
        }
        return"Record inserted successfully";
    }

    @GET
    @Path("/retrive")
    @Produces("text/html")
    @WebMethod(operationName = "retrive")
    public String retrive() 
    {
        ResultSet rs = null;
        String details = ""; 
        try 
        {
            Class.forName("com.mysql.jdbc.Driver");
            Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/studentinfo", "root", "root");

            String query = "select ID,NAME from CUSTOMER";

            PreparedStatement st = con.prepareStatement(query);
            rs = st.executeQuery();

            details = "<html><body>"; 
            details = details + "<table border=1>";
            details = details + "<tr><td><Strong>Id </Strong></td>" +
                                    "<td><Strong>Name </Strong></td>" + "</tr>";
            while (rs.next()) 
            {
                details = details + "<tr><td>" + rs.getInt("ID") + "</td>" +
                                        "<td>" + rs.getString("NAME") + "</td></tr>";
            }
            details += "</table></body></html>"; 
        } 
        catch (Exception e) 
        {
            System.out.println(e.getMessage());
        }   
        return details;
    }
}

插入.html：

 <!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=UTF-8">
<title>Insert</title>
</head>
<body>
    <form action="rest/user/fetch" method="POST">
        <p>
            Name : <input id="name" name="name" />
        </p>
        <input type="submit" value="Add" />
    </form>
    <form action="rest/user/retrive" method="GET">
        <input type="submit" value="Retrive" />
    </form>
</body>
</html>

我的web.xml是：

 <?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" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    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>FetchAndInsert</display-name>
    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
    <servlet>
        <servlet-name>REST Servlet</servlet-name>
        <servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
        <init-param>
            <param-name>com.sun.jersey.config.property.packages</param-name>
            <param-value>com.fetch</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>REST Servlet</servlet-name>
        <url-pattern>/rest/*</url-pattern>
    </servlet-mapping>
</web-app>
于 2012-04-11T11:46:26.900 回答
1

Jersey 不提供任何类型的 HTML 模板。您需要将响应转发到 jsp 页面或使用 Ajax 获取数据并将其放置在页面上。

于 2012-04-10T18:19:17.433 回答