如何使用Hibernate和Jersey在REST服务中进行POST

Question

我无法找到正确的格式以便在POST后将响应发送回.JSP页面。首先，如何获得Web服务对客户的响应？ 第二个问题是如何从Servlet调用客户端。

Answer 1

因为第二部分非常简单（在适当的doGet，doPost方法中在servlet中创建类实例），我将关注第一个问题。

片段在服务器端：

import java.math.BigInteger; 
import java.util.List; 
import java.util.logging.Logger; 

import javax.ws.rs.Consumes; 
import javax.ws.rs.GET; 
import javax.ws.rs.POST; 
import javax.ws.rs.Path; 
import javax.ws.rs.PathParam; 
import javax.ws.rs.Produces; 
import javax.ws.rs.core.MediaType; 
import javax.ws.rs.core.Response; 

import org.hibernate.SessionFactory; 

// internal beans and classes 
import com.deepam.util.BasicUtils; 

import entities.CustomerRest; 
import entities.DualInteger; 
import entities.Dualloc; 
import model.CustomerModel; 
import model.DualModel; 
import model.HibernateUtil; 

@Path("/customer") 
public class CustomerRestWS { 

    private final static Logger LOGGER = Logger.getLogger(CustomerRestWS.class.getName()); 

    private CustomerModel cm = new CustomerModel(); 
    private DualModel dm = new DualModel(); 
    private final String CUSTSEQ = "customer_rest_seq"; 

    SessionFactory sessionFactory; 

    /** Constructor 
    */ 
    public CustomerRestWS() { 
     super(); 
     LOGGER.info("***" + LOGGER.getName()); 
     sessionFactory = HibernateUtil.getSessionFactory(); 
    } 

...

@GET 
@Path("/findcustseq") 
@Produces(MediaType.APPLICATION_XML) 
public DualInteger selectCustSeq() { 
    return cm.selectCustSeqNative(CUSTSEQ); 
} 

// post method how to save customer into DB 
@POST 
@Path("/create") 
@Consumes(MediaType.APPLICATION_XML) 
@Produces(MediaType.APPLICATION_JSON) // JSON is used for clearity between Consumes/Produces on the Client side 
public Response create(final CustomerRest cust) throws JSONException { 
    Response response; 
    LOGGER.info("***" + LOGGER.getName() + " Insert Customer, id, name, last name: " + cust.getId() + ", " + cust.getFirstName() + ", " + cust.getLastName()); 
    try { 
     cm.create(cust); 
    } 
    catch (Exception ex) { 
     // internal error 
     LOGGER.info("***" + LOGGER.getName() + " Exception: " + ex.getMessage()); 
     response = Response.status(Response.Status.INTERNAL_SERVER_ERROR).entity(Response.Status.INTERNAL_SERVER_ERROR.toString()).build(); 
     return response; 
    } 
    // created 
    response = Response.status(Response.Status.CREATED) 
     .entity(Response.Status.CREATED.toString()).build(); 
    return response; 
} 

...

在客户端：

import java.text.MessageFormat; 
import java.util.logging.Logger; 

import javax.ws.rs.core.MediaType; 

import com.sun.jersey.api.client.Client; 
import com.sun.jersey.api.client.ClientResponse; 
import com.sun.jersey.api.client.UniformInterfaceException; 
import com.sun.jersey.api.client.WebResource; 
import com.sun.jersey.api.client.config.DefaultClientConfig; 

// internal beans 
import entities.Customer; 
import entities.DualInteger; 
import entities.ListCustomers; 

    public class CustomerRestfulClient { 
    private final static Logger LOGGER = Logger.getLogger(CustomerRestfulClient.class.getName()); 

    private WebResource webresource; 
    private Client client; 
    private static final String BASE_URI = "http://localhost:8080/RestfulOracleServer/rest/"; 

    public CustomerRestfulClient() { 
     // init client 
     client = Client.create(new DefaultClientConfig()); 
     // init webresource 
     webresource = client.resource(BASE_URI).path("customer"); 
    } 

...

/** method getCustIdXML for obtaining unique ID (from sequence) */ 
public DualInteger getCustIdXML() throws UniformInterfaceException { 
    WebResource resource = webresource.path(MessageFormat.format("findcustseq", new Object[] {})); 
    return resource.accept(MediaType.APPLICATION_XML).get(DualInteger.class); 
} 


/** method saveCustXML call other method to obtain unique ID, than save Bean to DB */ 
public ClientResponse saveCustXML(String firstName, String lastName) throws UniformInterfaceException { 
    DualInteger custId = getCustIdXML(); 
    LOGGER.info("Seqence number: " + (custId.getSeq())); 
    Customer cust = new Customer(custId.getSeq(), firstName, lastName); 
    ClientResponse response = webresource.path("create"). 
      accept(MediaType.APPLICATION_JSON).type(MediaType.APPLICATION_XML).post(ClientResponse.class, cust); 
    LOGGER.info("Entity: " + response.getStatus()); 
    return response; 
} 

注意服务器端的类Response和客户端的ClientResponse。看看如何在服务器端处理@Consumes,@Produces注释以及如何在客户端处理accept,type方法。有我的错误来源。 在用于.jsp的servlet控制器中，只需为WS创建Client即可。 custClient = new CustomerRestfulClient();在构造函数中使用明显的方法doGet,doPost。该Servlet有自己的Request,Response不同于WS的Request,Response。在MVC模型中谨慎，Controller被服务器视为Singleton。在并发环境中，您必须保持会话连续性。 （最简单的方法是在方法中使用局部变量，当它被指示时。）相似主题的链接： Is it ok by REST to return content after POST? RESTful Java Client with POST method