CXF发布restful WebService的入门例子(服务器端)

研究了两天CXF对restful的支持。 
  现在，想实现一个以 
http://localhost:9999/roomservice 为入口， 
http://localhost:9999/roomservice/room为房间列表, 
http://localhost:9999/roomservice/room/001/ 为001号房间的信息， 
http://localhost:9999/roomservice/room/001/person 为在001号房间主的人的列表 

实现用HTTP请求对以上资源的CRUD。 

首先建立room,person的POJO，这里只有一点需要注意：

package com.DAO;  
  
import javax.xml.bind.annotation.XmlRootElement;  
  
@XmlRootElement(name="Person")  
public class Person {  
    private String name;  
    private String sex;  
    public String getName() {  
        return name;  
    }  
    public void setName(String name) {  
        this.name = name;  
    }  
    public String getSex() {  
        return sex;  
    }  
    public void setSex(String sex) {  
        this.sex = sex;  
    }  
      
}  

一定要在类的前边加上annotation ，这样才能让这个person的信息在POJO和XML之间转换。Room同理: 

import java.util.Map;  
  
import javax.xml.bind.annotation.XmlRootElement;  
  
@XmlRootElement(name="Room")  
public class Room {  
    public Room()  
    {  
        persons=new HashMap<String,Person>();  
    }  
    String id;  
    Map<String,Person> persons;  
      
    public String getId() {  
        return id;  
    }  
    public void setId(String id) {  
        this.id = id;  
    }  
    public Map<String, Person> getPersons() {  
        return persons;  
    }  
    public void setPersons(Map<String, Person> persons) {  
        this.persons = persons;  
    }  
}  

POJO有了，接下来要写DAO，由于主要是为了学习restful，为了方便，不必要将数据持久化到数据库，而是存在一个静态的HashMap中： 

package com.DAO;  
  
import java.util.HashMap;  
import java.util.Map;  
  
public class RoomDAO {  
    private static Map<String, Room> rooms;  
    static {  
        rooms = new HashMap<String, Room>();  
          
        Person p1=new Person();  
        p1.setName("Boris");  
        p1.setSex("male");  
          
          
          
        Room r=new Room();  
        r.setId("001");  
        r.getPersons().put(p1.getName(), p1);  
        rooms.put("001", r);  
    }  
  
    public static void addRoom(Room room) {  
        rooms.put(room.getId(), room);  
    }  
  
    public static void deleteRoom(String id) {  
        if (rooms.containsKey(id)) {  
            rooms.remove(id);  
        }  
  
    }  
  
    public static void updateRoom(String id,Room room) {  
        rooms.remove(id);  
        rooms.put(room.getId(), room);  
    }  
  
    public static Room getRoom(String id) {  
        if (rooms.containsKey(id)) {  
            return rooms.get(id);  
        } else {  
            return null;  
        }  
    }  
    /*operations to persons*/  
    public static void addPerson(String id_room,Person person) {  
        if(rooms.containsKey(id_room))  
        {  
            Room room=rooms.get(id_room);  
            room.getPersons().put(person.getName(), person);  
        }  
    }  
      
    public static Rooms getRooms()  
    {  
        return new Rooms();  
    }  
      
    public static void deletePerson(String id_room,String name)  
    {  
        if(rooms.containsKey(id_room))  
        {  
            Room room=rooms.get(id_room);  
            room.getPersons().remove(name);  
        }  
    }  
      
    public static Map<String, Room> getMapOfRooms()  
    {  
        return rooms;  
    }  
}  

接下来是重点，如果想发布restful webservice，要通过一个叫JAXRSServerFactoryBean的类来发布。这个类有几个方法是要了解的： 

public void setResourceClasses(Class... classes); 
那一系列的Class类型的参数，是告诉这个类，发布服务时，会用到的POJO（就像上边写的Room,Person）。 

public void setAddress(String address)； 
这个方法是告诉这个类，服务的地址，比如"http://localhost:9999" 

public void setServiceBeans(Object... beans) 
这里是重点，这个方法，要给这个用来发布服务的类一个Service bean.这个Bean是我们要手动编写的，作用是告诉服务，收到什么样的请求，应该怎么样处理。 

现在，先来编写这个Service bean： 

package com.server;  
  
import javax.ws.rs.Consumes;  
import javax.ws.rs.DELETE;  
import javax.ws.rs.GET;  
import javax.ws.rs.POST;  
import javax.ws.rs.PUT;  
import javax.ws.rs.Path;  
import javax.ws.rs.PathParam;  
import javax.ws.rs.Produces;  
  
import com.DAO.Person;  
import com.DAO.Room;  
import com.DAO.RoomDAO;  
import com.DAO.Rooms;  
  
@Path("/roomservice")  
@Produces("application/xml")  
public class RoomService {  
      
    @GET  
    @Path("/room/{id}")  
    @Consumes("application/xml")  
    public Room getRoom(@PathParam("id")String id )  
    {  
        System.out.println("get room by id= "+id);  
        Room room=RoomDAO.getRoom(id);  
        return room;  
    }  
    @GET  
    @Path("/room")  
    @Consumes("application/xml")  
    public Rooms getAllRoom()  
    {  
        System.out.println("get all room");  
        Rooms rooms=RoomDAO.getRooms();  
        return rooms;  
    }  
      
    @POST  
    @Path("/room")  
    @Consumes("application/xml")  
    public void addRoom(Room room)  
    {  
        System.out.println("add room which id is:"+room.getId());  
        RoomDAO.addRoom(room);  
    }  
    @PUT  
    @Path("/room/{id}")  
    @Consumes("application/xml")  
    public void updateRoom(@PathParam("id")String id,Room room)  
    {  
        System.out.println("update room which original id is:"+room.getId());  
        RoomDAO.updateRoom(id,room);  
    }  
    @DELETE  
    @Path("/room/{id}")  
    @Consumes("application/xml")  
    public void deleteRoom(@PathParam("id")String id)  
    {  
        System.out.println("remove room by id= "+id);  
        RoomDAO.deleteRoom(id);  
    }  
    @POST  
    @Path("/room/{id}")  
    @Consumes("application/xml")  
    public void addPerson(@PathParam("id") String id,Person person)  
    {  
        System.out.println("add person who's name is:"+person.getName());  
        RoomDAO.addPerson(id, person);  
    }  
    @DELETE  
    @Path("/room/{id}/{name}")  
    @Consumes("application/xml")  
    public void deletePerson(@PathParam("id")String id,@PathParam("name")String name)  
    {  
        System.out.println("remove person who's name is: "+name);  
        RoomDAO.deletePerson(id, name);  
    }  
}  

需要注意：每个方法之前，要用annotation声明http请求的method类型，比如GET,DELETE,POST, PUT. 
@Produces("application/xml")我还没弄清楚到底是声明的接受格式还是返回格式，还是其他。 

@Path("/room/{id}")中的id是一个参数，应该在方法的参数列表中声明： 
public void deletePerson(@PathParam("id")String id,@PathParam("name")String name) 
这样就能得到URL中的id了。 

现在，这些房间被资源化了，id为001的房间被资源化为一个URL，那地址应该是 
http:{服务器地址}:{端口}/roomservice/rrom/001   

现在，创建一个Server： 

package com.server;  
  
import org.apache.cxf.jaxrs.JAXRSServerFactoryBean;  
  
import com.DAO.Person;  
import com.DAO.Room;  
import com.DAO.Rooms;  
  
public class Server {  
  
    public static void main(String[] args) {  
        RoomService service = new RoomService();  
  
        // Service instance  
        JAXRSServerFactoryBean restServer = new JAXRSServerFactoryBean();  
        restServer.setResourceClasses(Room.class,Person.class,Rooms.class);  
        restServer.setServiceBeans(service);  
        restServer.setAddress("http://localhost:9999/");  
        restServer.create();  
    }  
}  

现在，服务已经发布成功了，在浏览器输入http://localhost:9999/roomservice/room/001  得到结果： 

<room>  
<id>001</id>  
−  
<persons>  
−  
<entry>  
<key>Boris</key>  
−  
<value>  
<name>Boris</name>  
<sex>male</sex>  
</value>  
</entry>  
</persons>  
</room>  

如果用浏览器去访问，发送的http请求只能所GET,因此如果想对数据进行操作，必须写一个客户端。 
在写客户端之前，有一个问题： 
在浏览器输入http://localhost:9999/roomservice/room/ 
什么都看不到，可是，我想要得到房间列表。但是，cxf发布restful只认你给他的类的class。所以你想让服务器返回一个room的列表给客户端，是不行的。所以，必须想别的办法，我是又写了一个POJO，这个POJO里只有一个属性，就是一个存放所有room的Map： 
package com.DAO; 

import java.util.Map;  
  
import javax.xml.bind.annotation.XmlRootElement;  
@XmlRootElement(name="rooms")  
public class Rooms {  
    Map<String,Room> rooms;  
    public Rooms()  
    {  
        rooms=RoomDAO.getMapOfRooms();  
    }  
    public Map<String, Room> getRooms() {  
        return rooms;  
    }  
    public void setRooms(Map<String, Room> rooms) {  
        this.rooms = rooms;  
    }  
}  

这样，然后再把DAO的方法加上： 

@GET  
    @Path("/room")  
    @Consumes("application/xml")  
    public Rooms getAllRoom()  
    {  
        System.out.println("get all room");  
        Rooms rooms=RoomDAO.getRooms();  
        return rooms;  
    }  

这样就能以list的形式显示出所有room了。 
访问http://localhost:9999/roomservice/room/ 
结果如下： 

<rooms>  
−  
<rooms>  
−  
<entry>  
<key>006</key>  
−  
<value>  
<id>006</id>  
<persons/>  
</value>  
</entry>  
−  
<entry>  
<key>001</key>  
−  
<value>  
<id>001</id>  
−  
<persons>  
−  
<entry>  
<key>Boris</key>  
−  
<value>  
<name>Boris</name>  
<sex>male</sex>  
</value>  
</entry>  
</persons>  
</value>  
</entry>  
</rooms>  
</rooms>  

转自 http://borissun.iteye.com/blog/765869