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;@Repositorypublic 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 {@Autowiredprivate 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 stubSystem.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……