前言
续上篇Apache CXF 101,摘抄部分REST概念性知识,以运行实例考察CXF对REST的支持。
目录
1 REST简介
2 工具
3 运行实例
内容
本Spike记录中内容,如无特别指出,均引用[1]。
1 REST简介
有两种实现Web Service的主要方式:SOAP(Simple Object Access
Protocl)和REST架构风格(Representational State Transfer architecture style)。
用REST架构风格构建的服务(RESTful服务),用简单的XML等形式封装数据、通过HTTP传输数据。
与基于SOAP的服务开发方法相比,施加于服务开发者的技术负担更小,特别是服务只需发送和接收简单的XML消息时。
REST架构风格是关于资源的,资源是用URI(Uniform Resource
Indicator)标识的表示(representation)。
资源可以是任意信息,例如Book、Order等。客户通过交换资源的表示来查询或更新URI标识的资源。
表示中包含以具体格式记录的实际信息,常见的格式有HTML/XML/JSON。客户通常可以指定它/他/她需要的表示。所有处理特定资源上的信息均包含于请求自身,使得交互是无状态的。
用REST架构风格原则构建的Web服务称为RESTful Web服务。RESTful Web服务可视为可通过URI标识的资源。RESTful
Web服务用标准的HTTP方法(GET/POST…)暴露操作的集合。客户使用HTTP协议通过URI访问/调用这些方法。
RESTful Service URI
example
http://cxf.spike.com/department/deptname/employee
GET 返回部门中雇员列表
POST 创建部门中雇员记录
DELETE 删除部门中雇员记录
JSR
support
JAX-RS[2]
JAS-RS定义这些目标:
? POJO为中心
JAX-RS
API提供了一组注解和相关的类/接口,将POJO暴露为RESTful资源。
? HTTP为中心
RESTful资源通过HTTP协议暴露,该规范提供了清晰的HTTP协议与相关的JAX-RS
API中类、方法之间的映射。同时提供了如何匹配HTTP请求到资源类和方法的指南。
? 格式独立
该API提供了一种可插拔机制,该机制允许以标准的方式添加HTTP内容类型。
? 容器独立
用JAX-RS开发的应用应该可以运行于任意容器中。该规范定义了如何用JAX-RS
API部署应用的标准机制。
? Java企业版容器包含
该规范定义了RESTful资源如何宿于Java
EE6容器和如何利用容器提供的功能。
JAX-RS的实现[3]
Apache
CXF开源的Web服务框架。
Jersey由Sun提供的JAX-RS的参考实现。
RESTEasy JBoss的实现。
Restlet由Jerome
Louvel和Dave Pawson开发,是最早的REST框架,先于JAX-RS出现。
Apache
Wink一个Apache软件基金会孵化器中的项目,其服务模块实现JAX-RS规范
2 工具
Firefox插件:Poster(https://addons.mozilla.org/en-US/firefox/addon/poster/)
安装后工具位置
工具面板
用数据测试
结果呈现
3 运行实例
Book Shop Application
Functionality:
(1) Category CRUD
(2) Add Books
to a Category
(3) Getting Books belongs to a Category
[1]中指出了(CXF) RESTful服务开发实践步骤
(1) 创建Request/Response的Java数据对象
(2) 绑定Request/Response对象
(3) 创建RESTful实现:创建实现类并用JAX-RS注解
(4) 服务单元测试
(5) 创建客户端,调用服务方法
(6) 将服务部署于容器中
(1) 创建Request/Response的Java数据对象
(2) 绑定Request/Response对象
两个JAXB绑定的pojo,JAXB是CXF默认的绑定方式
Book
package demo.restful.pojo;import javax.xml.bind.annotation.XmlRootElement;
/**
* Description: Book<br/>
* Date: 2014-5-12 下午10:54:16
*/
@XmlRootElement(name = "Book")
public class Book {
private String bookId;
private String bookISBNnumber;
private String bookName;
private String author;//one author onlypublic 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;
}@Override
public String toString() {
return "Book [bookId=" + bookId + ", bookISBNnumber=" + bookISBNnumber + ", bookName=" + bookName + ", author=" + author + "]";
}}
Category
package demo.restful.pojo;import java.util.List;
import javax.xml.bind.annotation.XmlRootElement;
/**
* Description: Category<br/>
* Date: 2014-5-12 下午10:53:52
*/
@XmlRootElement(name = "Category")
public class Category {
private String categoryId;
private String categoryName;
private List<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 List<Book> getBooks() {
return books;
}public void setBooks(List<Book> books) {
this.books = books;
}@Override
public String toString() {
return "Category [categoryId=" + categoryId + ", categoryName=" + categoryName + ", books=" + books + "]";
}}
(3) 创建RESTful实现:创建实现类并用JAX-RS注解
CategoryService接口
package demo.restful.service;import javax.ws.rs.core.Response;
import demo.restful.pojo.Category;
/**
* Description: Category Service Interface With Exception Handling<br/>
* Date: 2014-5-12 下午11:12:02
*/
public interface CategoryService {public Category getCategory(String id);
public Response addCategory(Category category);
public Response deleteCategory(String id);
public Response updateCategory(Category category);
public Response addBooks(Category category);
public Response getBooks(String id);
}
CategoryService实现类
package demo.restful.service;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.WebApplicationException;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.Response.ResponseBuilder;
import javax.ws.rs.core.Response.Status;import demo.restful.data.CategoryDAO;
import demo.restful.pojo.Category;/**
* Description: Category Service Implementation With Exception Handling<br/>
* Date: 2014-5-12 下午11:12:02
*/
@Path("/categoryservice")
@Produces({ "application/xml", "application/json" })
public class CategoryServiceImpl implements CategoryService {
private CategoryDAO categoryDAO;//wiredpublic 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 = (Category) getCategoryDAO().getCategory(id);
if (cat == null) {
ResponseBuilder builder = Response.status(Status.BAD_REQUEST);
builder.type("application/xml");
builder.entity("<error>Category Not Found</error>");
throw new WebApplicationException(builder.build());
} else {
return cat;
}
}@POST
@Path("/category")
@Consumes({ "application/xml", "application/json" })
public Response addCategory(Category category) {
System.out.println("addCategory called");
Category cat = (Category) getCategoryDAO().getCategory(category.getCategoryId());
if (cat != null) {
return Response.status(Status.BAD_REQUEST).build();
} else {
getCategoryDAO().addCategory(category);
return Response.ok(category).build();
}
}@DELETE
@Path("/category/{id}")
public Response deleteCategory(@PathParam("id") String id) {
System.out.println("deleteCategory with category id : " + id);
Category cat = (Category) getCategoryDAO().getCategory(id);
if (cat == null) {
return Response.status(Status.BAD_REQUEST).build();
} else {
getCategoryDAO().deleteCategory(id);
return Response.ok().build();
}
}@PUT
@Path("/category")
public Response updateCategory(Category category) {
System.out.println("updateCategory with category id : " + category.getCategoryId());
Category cat = (Category) getCategoryDAO().getCategory(category.getCategoryId());
if (cat == null) {
return Response.status(Status.BAD_REQUEST).build();
} else {
getCategoryDAO().updateCategory(category);
return Response.ok(category).build();
}
}@POST
@Path("/category/book")
@Consumes({ "application/xml", "application/json" })
public Response addBooks(Category category) {
System.out.println("addBooks with category id : " + category.getCategoryId());
Category cat = (Category) getCategoryDAO().getCategory(category.getCategoryId());
if (cat == null) {
return Response.status(Status.NOT_FOUND).build();
} else {
getCategoryDAO().addBook(category);
return Response.ok(category).build();
}
}@GET
@Path("/category/{id}/books")
@Consumes({ "application/xml", "application/json" })
public Response getBooks(@PathParam("id") String id) {
System.out.println("getBooks called with category id : " + id);
Category cat = (Category) getCategoryDAO().getCategory(id);
if (cat == null) {
return Response.status(Status.NOT_FOUND).build();
} else {
cat.setBooks(getCategoryDAO().getBooks(id));
return Response.ok(cat).build();
}
}
}
View
Code
以内存中Map实现的DAO:服务支持类CategoryDAO
package demo.restful.data;import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;import demo.restful.pojo.Book;
import demo.restful.pojo.Category;/**
* Description: Category DAO Stub Implementation<br/>
* Date: 2014-5-12 下午11:22:17
*/
public class CategoryDAO {
//category-id : category
private static Map<String, Category> categoryMap = new HashMap<String, Category>();
//category-id : books
private static Map<String, List<Book>> bookMap = new HashMap<String, List<Book>>();
static {
//Populate some static data
Category category1 = new Category();
category1.setCategoryId("001");
category1.setCategoryName("Java");
categoryMap.put(category1.getCategoryId(), category1);
Book book1 = new Book();
book1.setAuthor("Naveen Balani");
book1.setBookName("Spring Series");
book1.setBookId("001");
book1.setBookISBNnumber("ISB001");
Book book2 = new Book();
book2.setAuthor("Rajeev Hathi");
book2.setBookName("CXF Series");
book2.setBookId("002");
book2.setBookISBNnumber("ISB002");
List<Book> booksList = new ArrayList<Book>();
booksList.add(book1);
booksList.add(book2);
bookMap.put(category1.getCategoryId(), booksList);
}public void addCategory(Category category) {
categoryMap.put(category.getCategoryId(), category);
}//Add Books associated with the Category
public void addBook(Category category) {
bookMap.put(category.getCategoryId(), category.getBooks());
}public List<Book> getBooks(String categoryId) {
return bookMap.get(categoryId);
}public Category getCategory(String id) {
Category cat = null;
//Dummy implementation to return a new copy of category to
//avoid getting overridden by service
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);
// Remove association of books
bookMap.remove(id);
}public void updateCategory(Category category) {
categoryMap.put(category.getCategoryId(), category);
}
}
(4) 服务单元测试
因服务有灵活的部署方式,部署在Servlet容器中上一篇记录中已经有所说明,另一种方式是以常规应用程序直接运行在JVM中。
Server实现
Spring配置文件restapp.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"><bean id="categoryService" class="demo.restful.service.CategoryServiceImpl">
<property name="categoryDAO">
<ref bean="categoryDAO" />
</property>
</bean><bean id="categoryDAO" class="demo.restful.data.CategoryDAO">
</bean>
</beans>
常量类
package demo.restful;/**
* Description: 常量类<br/>
* Date: 2014-5-12 下午11:41:09
*/
public class Constants {
public static final String SERVICE_URL = "http://localhost:9000/";
}
Server
package demo.restful.server;import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;import org.apache.cxf.jaxrs.JAXRSServerFactoryBean;
import org.springframework.context.support.ClassPathXmlApplicationContext;import demo.restful.Constants;
import demo.restful.pojo.Book;
import demo.restful.pojo.Category;
import demo.restful.service.CategoryService;
import demo.restful.service.CategoryServiceImpl;/**
* Description: Server<br/>
* Date: 2014-5-12 下午11:37:09
*/
public class Server {
public static void main(String[] args) {
ClassPathXmlApplicationContext appContext = new ClassPathXmlApplicationContext(new String[] { "/demo/restful/restapp.xml" });
CategoryService categoryService = (CategoryServiceImpl) appContext.getBean("categoryService");// Service instance
JAXRSServerFactoryBean restServer = new JAXRSServerFactoryBean();
restServer.setResourceClasses(Category.class, Book.class);
restServer.setServiceBean(categoryService);
restServer.setAddress(Constants.SERVICE_URL);
restServer.create();BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
try {
br.readLine();
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("Server Stopped");
System.exit(0);
}
}
这样自然的,单元测试就有两种方法:部署在Servlet容器中的服务以浏览器/Poster测试,以常规应用程序部署的服务则可以编写JUnit单元测试。
Poster测试
这里用到的Poster的两个主要设置:
"Content to Send"label中将"Content
Type"设置为application/xml(或application/json,视准备数据而定)
"Header"label中添加Name: Accept, Value: application/xml(或application/json)
新增Category
更新Category
JUnit单元测试
HTTPClient - 简单的服务客户端示例
package demo.restful.client;import java.util.Iterator;
import org.apache.cxf.jaxrs.client.WebClient;
import demo.restful.pojo.Book;
import demo.restful.pojo.Category;/**
* Description: HTTP Client<br/>
* Date: 2014-5-12 下午11:57:41
*/
public class HTTPClient {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 REST service.");
System.out.println("Category Name " + category.getCategoryName());
System.out.println("Category Id " + category.getCategoryId());
System.out.println("Book details for Category " + category.getCategoryId() + " from REST service");
String bookString = "categoryservice/category/" + category.getCategoryId() + "/books";
WebClient clientBook = WebClient.create("http://localhost:9000/");
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());
}
}}
RESTCategoryService,测试媒体类型application/xml,为直观显示执行结果,未使用JUnit断言。
package demo.restful.client;import java.util.ArrayList;
import java.util.List;
import java.util.UUID;import javax.ws.rs.core.Response;
import org.apache.cxf.jaxrs.client.WebClient;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;
import demo.restful.pojo.Book;
import demo.restful.pojo.Category;/**
* Description: RESTCategoryService in Servlet Container Unit test<br/>
* Date: 2014-5-13 下午9:41:27
*/
public class RESTCategoryServiceTest {
private WebClient client = null;
private static final String FORMAT = "application/xml";
private static String id = null;@BeforeClass
public static void setUpBeforClass() {
id = newId();
}@Before
public void setUp() {
client = WebClient.create("http://localhost:8082/CXF/");
}@Test
public void getCategory() {
System.out.println("======================getCategory");
Category category = client.path("categoryservice/category/001").accept(FORMAT).get(Category.class);
System.out.println(category);
System.out.println("======================getCategory");}
@Test
public void addCategory() {
System.out.println("======================addCategory");
Category category = new Category();
category.setCategoryId(id);
category.setCategoryName(".NET");
System.out.println("Add " + category + "...");
Category response = client.path("categoryservice/category").accept(FORMAT).type(FORMAT).post(category, Category.class);
System.out.println(response);
//test using query
System.out.println("Get category " + id + "...");
client = WebClient.create("http://localhost:8082/CXF/");//new WebClient!!!
System.out.println(client.path("categoryservice/category/" + id).accept(FORMAT).get(Category.class));
System.out.println("======================addCategory");
}@Test
public void updateCategory() {
System.out.println("======================updateCategory");
Category category = new Category();
category.setCategoryId(id);
category.setCategoryName("Microsoft .NET");
Response response = client.path("categoryservice/category").put(category);
System.out.println(response.getStatus());
System.out.println(response.getEntity());
System.out.println("======================updateCategory");}
@Test
public void addBooks() {
System.out.println("======================addBooks");
client.path("/categoryservice/category/book").type(FORMAT).accept(FORMAT);
Category cat = new Category();
cat.setCategoryId(id);
cat.setCategoryName("Fiction Series");
Book book1 = new Book();
book1.setAuthor("Naveen Balani");
book1.setBookId("NB001");
book1.setBookISBNnumber("ISBNB001");
book1.setBookName("Fiction Book1");
List<Book> booksList = new ArrayList<Book>();
booksList.add(book1);
cat.setBooks(booksList);
Category response = client.post(cat, Category.class);
System.out.println(response);
System.out.println("======================addBooks");
}@Test
public void getBooks() {
System.out.println("======================getBooks");
Category category = client.path("/categoryservice/category/" + id + "/books").accept(FORMAT).get(Category.class);
System.out.println("Book details retreived from service with format " + FORMAT);
List<Book> books = category.getBooks();
for (Book book : books) {
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());
}
System.out.println("======================getBooks");
}@Test
public void deleteCategory() {
System.out.println("======================deleteCategory");
Response response = client.path("categoryservice/category/" + id).delete();
System.out.println(response.getStatus());
System.out.println("======================deleteCategory");
}private static String newId() {
return UUID.randomUUID().toString().replaceAll("\\-", "").toUpperCase();
}
}
JSONRESTCategoryServiceTest,与RESTCategoryService基本相同,唯一的区别在于媒体类型为application/json
package demo.restful.client;import java.util.ArrayList;
import java.util.List;
import java.util.UUID;import javax.ws.rs.core.Response;
import org.apache.cxf.jaxrs.client.WebClient;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;
import demo.restful.pojo.Book;
import demo.restful.pojo.Category;/**
* Description: JSONRESTCategoryService in Servlet Container Unit test<br/>
* Date: 2014-5-13 下午9:41:27
*/
public class JSONRESTCategoryServiceTest {
private WebClient client = null;
private static final String FORMAT = "application/json";
private static String id = null;@BeforeClass
public static void setUpBeforClass() {
id = newId();
}@Before
public void setUp() {
client = WebClient.create("http://localhost:8082/CXF/");
}@Test
public void getCategory() {
System.out.println("======================getCategory");
Category category = client.path("categoryservice/category/001").accept(FORMAT).get(Category.class);
System.out.println(category);
System.out.println("======================getCategory");}
@Test
public void addCategory() {
System.out.println("======================addCategory");
Category category = new Category();
category.setCategoryId(id);
category.setCategoryName(".NET");
System.out.println("Add " + category + "...");
Category response = client.path("categoryservice/category").accept(FORMAT).type(FORMAT).post(category, Category.class);
System.out.println(response);
//test using query
System.out.println("Get category " + id + "...");
client = WebClient.create("http://localhost:8082/CXF/");//new WebClient!!!
System.out.println(client.path("categoryservice/category/" + id).accept(FORMAT).get(Category.class));
System.out.println("======================addCategory");
}@Test
public void updateCategory() {
System.out.println("======================updateCategory");
Category category = new Category();
category.setCategoryId(id);
category.setCategoryName("Microsoft .NET");
Response response = client.path("categoryservice/category").put(category);
System.out.println(response.getStatus());
System.out.println(response.getEntity());
System.out.println("======================updateCategory");
}@Test
public void addBooks() {
System.out.println("======================addBooks");
client.path("/categoryservice/category/book").type(FORMAT).accept(FORMAT);
Category cat = new Category();
cat.setCategoryId(id);
cat.setCategoryName("Fiction Series");
Book book1 = new Book();
book1.setAuthor("Naveen Balani");
book1.setBookId("NB001");
book1.setBookISBNnumber("ISBNB001");
book1.setBookName("Fiction Book1");
List<Book> booksList = new ArrayList<Book>();
booksList.add(book1);
cat.setBooks(booksList);
Category response = client.post(cat, Category.class);
System.out.println(response);
System.out.println("======================addBooks");
}@Test
public void getBooks() {
System.out.println("======================getBooks");
Category category = client.path("/categoryservice/category/" + id + "/books").accept(FORMAT).get(Category.class);
System.out.println("Book details retreived from service with format " + FORMAT);
List<Book> books = category.getBooks();
for (Book book : books) {
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());
}
System.out.println("======================getBooks");
}@Test
public void deleteCategory() {
System.out.println("======================deleteCategory");
Response response = client.path("categoryservice/category/" + id).delete();
System.out.println(response.getStatus());
System.out.println("======================deleteCategory");
}private static String newId() {
return UUID.randomUUID().toString().replaceAll("\\-", "").toUpperCase();
}
}
(5) 创建客户端,调用服务方法
见HTTPClient示例。
(6) 将服务部署于容器中
上一篇记录中已经有所说明。
参考资料
[1]Balani N., Hathi R..Apache CXF web service development Develop and
deploy SOAP and RESTful web service[M]. Birmingham: Packet Publishing.
2009.
[2]JSR311: JAX-RS: The JavaTM API for RESTful Web
Services[EB/OL]. https://jcp.org/en/jsr/detail?id=311.
2014-05-12.
[3]JAX-RS. Wiki.
http://zh.wikipedia.org/wiki/JAX-RS. 2014-05-12.