基于CXF webService（5）REST service

利用webservice交互有SOAP和REST两种方式，SOAP是协议，REST不是协议，它是一个过程，利用HTTP协议对应的GET，POST，PUT，DELETE四种方法对应查、增、改、删中方式。REST比较松散，它用来对资源数据的传输，效率高，但是还是要根据实际情况选择SOAP还是REST方式。

对于REST，官网给出了三种方式，第一种java方式，第二种jaxws方式，第三种（已经淘汰），本例我是第一种方式，第二种方式官网的例子本人也测试过，很简洁，但是不是很好懂，资料上一般都选第一种方式基于jaxrs的。（官网太不详细：http://cxf.apache.org/docs/restful-services.html）

下面给出一个我实现了的例子来说明。

首先来看看我的项目结构：



我们把基础的类

Book.java和Category.java先展示如下：

package demo.restful;

import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement(name="Book")
public class Book {
private String bookId;
private String bookISBNnumber;
private String bookName;
private String author;
public String getBookId() {
return bookId;
}
public void setBookId(String bookId) {
this.bookId = bookId;
}
public String getBookISBNnumber() {
return bookISBNnumber;
}
public void setBookISBNnumber(String bookISBNnumber) {
this.bookISBNnumber = bookISBNnumber;
}
public String getBookName() {
return bookName;
}
public void setBookName(String bookName) {
this.bookName = bookName;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}

}

package demo.restful;

import java.util.Collection;

import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement(name="Category")
public class Category {
private String categoryId;
private String categoryName;
private Collection<Book> books;
public String getCategoryId() {
return categoryId;
}
public void setCategoryId(String categoryId) {
this.categoryId = categoryId;
}
public String getCategoryName() {
return categoryName;
}
public void setCategoryName(String categoryName) {
this.categoryName = categoryName;
}
public Collection<Book> getBooks() {
return books;
}
public void setBooks(Collection<Book> books) {
this.books = books;
}

}

数据操作的Dao类

package demo.restful;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

import org.springframework.stereotype.Repository;

@Repository
public class CategoryDAO {

private static Map<String,Category> categoryMap= new HashMap<String,Category>();
private static Map<String,Collection<Book>> bookMap = new HashMap<String, Collection<Book>>();
static{
Category category1 = new Category();
category1.setCategoryId("001");
category1.setCategoryName("Java");
categoryMap.put(category1.getCategoryId(), category1);

Book book1 = new Book();
book1.setAuthor("Tian jun");
book1.setBookName("Spring MVC");
book1.setBookId("001");
book1.setBookISBNnumber("isbn001");

Book book2 = new Book();
book2.setAuthor("t jun123");
book2.setBookName("CXF WEB SERvice");
book2.setBookId("002");
book2.setBookISBNnumber("isbn002");

Collection<Book> bookList = new ArrayList<Book>();
bookList.add(book1);
bookList.add(book2);

bookMap.put(category1.getCategoryId(), bookList);

}

public  void addCategory(Category category){
categoryMap.put(category.getCategoryId(), category);
}

public void addBook(Category category){
bookMap.put(category.getCategoryId(), category.getBooks());
}

public Collection<Book> getBooks(String categoryId) {
return bookMap.get(categoryId);
}

public Category getCategory(String id){
Category cat =null;

if(categoryMap.get(id)!=null){
cat = new Category();
cat.setCategoryId(categoryMap.get(id).getCategoryId());
cat.setCategoryName(categoryMap.get(id).getCategoryName());
}
return cat ;
}

public void deleteCategory(String id){
categoryMap.remove(id);
bookMap.remove(id);
}

public void updateCategory(Category category){
categoryMap.put(category.getCategoryId(), category);
}
}

业务逻辑类，也是进行消息处理的映射类

package demo.restful;

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 javax.ws.rs.core.Response;
import javax.ws.rs.core.Response.Status;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
@Path("/categoryservice")
@Produces("application/xml")
public class CategoryService {

@Autowired
private CategoryDAO categoryDAO;

public CategoryDAO getCategoryDao() {
return categoryDAO;
}

public void setCategoryDao(CategoryDAO categoryDao) {
this.categoryDAO = categoryDao;
}

@GET
@Path("/category/{id}")
public Category getCategory(@PathParam("id") String id){
System.out.println("getcategory called with category id:"+id);
Category cat = getCategoryDao().getCategory(id);
return cat;
}

@POST
@Path("/category")
@Consumes("application/xml")
public  void addCategory(Category category){
System.out.println("addcategory called");
Category cat = getCategoryDao().getCategory(category.getCategoryId());
if(cat != null){
//			return Response.status(Status.BAD_REQUEST).build();
getCategoryDao().addCategory(category);
}
//		else{
getCategoryDao().addCategory(category);
//			return Response.ok(category).build();
//		}

}

@DELETE
@Path("/catagory/{id}")
public void deleteCategory(@PathParam("id") String id){
System.out.println("deleteCategory with category id:"+id);
getCategoryDao().deleteCategory(id);
}

@PUT
@Path("/category")
public void updateCategory(Category category){
System.out.println("updateCategory with id:"+category.getCategoryId());
getCategoryDao().updateCategory(category);
}

@POST
@Path("/category/book")
@Consumes("application/xml")
public void addBooks(Category category){
System.out.println("addBook with category id:"+category.getCategoryId());
Category cat = getCategoryDao().getCategory(category.getCategoryId());
getCategoryDao().addBook(category);
}

@GET
@Path("/category/{id}/books")
@Consumes("application/xml")
public Category getBooks(@PathParam("id") String id){
System.out.println("getBooks called with id:"+id);
Category cat = getCategoryDao().getCategory(id);
cat.setBooks(getCategoryDao().getBooks(id));
return cat;
}
}

最后启动服务端：

</pre><pre name="code" class="java">package demo.restful;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;

import org.apache.cxf.jaxrs.JAXRSServerFactoryBean;
import org.apache.cxf.jaxrs.lifecycle.ResourceProvider;
import org.apache.cxf.jaxrs.lifecycle.SingletonResourceProvider;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class CategoryServiceStart {

public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println("==============");
ClassPathXmlApplicationContext appcontext = new ClassPathXmlApplicationContext(new String[]{"restapp.xml"});
CategoryService categoryservice = (CategoryService) appcontext.getBean("categoryService");
JAXRSServerFactoryBean restServer = new JAXRSServerFactoryBean();
restServer.setResourceClasses(Category.class);
restServer.setServiceBean(categoryservice);
restServer.setAddress("http://localhost:9000/");
restServer.create();

//		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
//		try{
//			br.readLine();
//		}catch (IOException e){
//			e.printStackTrace();
//		}
//		System.out.println("*************$$$$$$$$**********************");

//		List<Class<?>> resourceClassList = new ArrayList<Class<?>>();
//		resourceClassList.add(CategoryService.class);
//
//		List<ResourceProvider> resourceProviderList= new ArrayList<ResourceProvider>();
//		resourceProviderList.add(new SingletonResourceProvider(new CategoryService()));
//
//		List<Object> providerList = new ArrayList<Object>();
//		providerList.add(new jackson);
//
//		JAXRSServerFactoryBean factory = new JAXRSServerFactoryBean();
//		factory.setAddress("http://localhost:8080/WS/rest");
//		factory.setResourceClasses(resourceClassList);
//		factory.setResourceProviders(resourceProviderList);
//		factory.setProvider(providerList);
//		factory.create();

System.out.println("rest ws is publish....");

}

}

可以直接在浏览器中输入如下：
http://localhost:9000/categoryservice/category/001
看到如下：

<Category>

<categoryId>001</categoryId>
<categoryName>Java</categoryName>

</Category>

浏览器中输入：
http://localhost:9000/categoryservice/category/001/books
看到如下：

<Category>

<books>

<author>Tian jun</author>
<bookISBNnumber>isbn001</bookISBNnumber>
<bookId>001</bookId>
<bookName>Spring MVC</bookName>

</books>

<books>

<author>t jun123</author>
<bookISBNnumber>isbn002</bookISBNnumber>
<bookId>002</bookId>
<bookName>CXF WEB SERvice</bookName>

</books>

<categoryId>001</categoryId>
<categoryName>Java</categoryName>

</Category>

当然我们也可以编写客户端来实现：

代码如下：

package demo.restful.client;

import java.util.Iterator;

import javax.ws.rs.core.MediaType;

import org.apache.cxf.jaxrs.client.WebClient;

import demo.restful.Book;
import demo.restful.Category;

public class CategoryServiceClient {
public static void main(String[] args) {
WebClient client = WebClient.create("http://localhost:9000/");
Category category = client.path("categoryservice/category/001").accept("application/xml").get(Category.class);
System.out.println("category details from RESTful service...");
System.out.println("category Name "+category.getCategoryName());
System.out.println("category id "+category.getCategoryId());

System.out.println("Book details for categroy "+category.getCategoryId()+" from REST service");
String bookString ="categoryservice/category/"+category.getCategoryId()+"/books";

WebClient clientBook = WebClient.create("http://localhost:9000/");
try{

Category categorybooks = clientBook.path(bookString).accept("application/xml").get(Category.class);

Iterator<Book> iterator = categorybooks.getBooks().iterator();
while(iterator.hasNext()){
Book book = iterator.next();
System.out.println("book name:"+book.getBookName());
System.out.println("book isbn:"+book.getBookISBNnumber());
System.out.println("book id:"+book.getBookId());
System.out.println("book author:"+book.getAuthor());
}

}catch(Exception e){
e.printStackTrace();
}

}

}

效果如下：



如图大家看到的是编写Application发布实现的，由于我们是web，所以想利用Spring发布到服务器上。

资料和网上的都是利用jaxrs：server属性来实现的，我用的CXF是最新的3.1.1的版本，写上jaxrs：server属性，不提示错，但是编译的时候会爆没这个属性，官网信息太零散了，我还没找到最新版本的spring发布方式，有知道的可以告诉一声或交流下，不剩感激……