Restlet - 基于Spring的Restlet开发实例

一、相关说明

    version：文中示例使用的Spring版本为3.0.3，Restlet版本为2.1.0。

    entity：Student

二、创建Java Web工程，添加相关Jar。文中示例工程名为SpringRestlet。

    


    说明：动态代理的cglib-nodep.jar不可缺少。

三、web.xml配置

<servlet>
<servlet-name>dispatcherServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath*:/applicationContext.xml</param-value>
</init-param>
</servlet>
<!--Spring ApplicationContext load -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- Spring,avoid leaking memory -->
<listener>
<listener-class>org.springframework.web.util.IntrospectorCleanupListener</listener-class>
</listener>
<filter>
<filter-name>encodingFilter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
<init-param>
<param-name>forceEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<!-- restlet servlet -->
<servlet>
<servlet-name>restlet</servlet-name>
<servlet-class>org.restlet.ext.spring.SpringServerServlet</servlet-class>
<init-param>
<param-name>org.restlet.application</param-name>
<param-value>application</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>restlet</servlet-name>
<url-pattern>/*</url-pattern>
</servlet-mapping>

四、Model实体类代码

@JsonSerialize(include = Inclusion.NON_NULL)
public class Student {
private Integer id;
private String name;
private Integer sex;
private Integer age;

public Student() {
}
/** setter/getter **/
}

    说明：@JsonSerialize(include = Inclusion.NON_NULL)为JackSon的注解，作用是返回JSON格式的实体时不返回该实体类值为Null的Field，如： {"id" : 1,"name" : null,"sex" : 1,"age" : 20} 。

五、Resource代码

    1、StudentResource：示例中主要针对单个实例的Retrieve、Update和Delete。

@Controller
@Scope("prototype")
public class StudentResource extends ServerResource {
private Integer id;
@Autowired
private StudentBO studentBO;

public void setStudentBO(StudentBO studentBO) {
this.studentBO = studentBO;
}

@Override
protected void doInit() throws ResourceException {
id = Integer.valueOf((String) getRequestAttributes().get("studentId"));
}

@Get("json")
public Student findStudentById() {
Student s = this.studentBO.getStudent(id);
return s;
}

@Delete("json")
public Integer deleteStudentById() {
return this.studentBO.removeStudent(id);
}

@Put("json")
public Integer updateStudent(Student student) {
student.setId(id);
return this.studentBO.saveOrUpdateStudent(student);
}
}

    2、StudentListResource：示例中主要针对单个实例的Create和多个实例的Retrieve。

@Controller
@Scope("prototype")
public class StudentListResource extends ServerResource {
@Autowired
private StudentBO studentBO;

@Post
public Integer saveStudent(Student student) {
return studentBO.saveOrUpdateStudent(student);
}

@Get("json")
public List<Student> findStudentAll() {
return studentBO.getStudentAll();
}

public void setStudentBO(StudentBO studentBO) {
this.studentBO = studentBO;
}
}

    说明：接受Spring管理的Bean，@Scope("prototype")的annotation必须要有，否则会出现正确调用指定方法的问题，用xml配置Bean时也必须要Attribute:scope。

六、BusinessObject代码

@Service
@Scope("prototype")
public class StudentBO {
private static Map<Integer, Student> students = new HashMap<Integer, Student>();
// next Id
private static int nextId = 5;
static {
students.put(1, new Student(1, "Michael", 1, 18));
students.put(2, new Student(2, "Anthony", 1, 22));
students.put(3, new Student(3, "Isabella", 0, 19));
students.put(4, new Student(4, "Aiden", 1, 20));
}

public Student getStudent(Integer id) {
return students.get(id);
}

public List<Student> getStudentAll() {
return new ArrayList<Student>(students.values());
}

public Integer saveOrUpdateStudent(Student student) {
if (student.getId() == null) {
student.setId(nextId++);
}
students.put(student.getId(), student);
return student.getId();
}

public Integer removeStudent(Integer id) {
students.remove(id);
return id;
}
}

七、Spring applictionContext.xml配置

<!-- 该application在web.xml中引用  -->
<bean name="application" class="org.restlet.Application">
<property name="inboundRoot">
<bean class="org.restlet.ext.spring.SpringRouter">
<constructor-arg ref="application"/>
<property name="attachments">
<map>
<entry key="/student/{studentId}">
<bean class="org.restlet.ext.spring.SpringFinder">
<lookup-method name="create" bean="studentResource"/>
</bean>
</entry>
<entry key="/student">
<bean class="org.restlet.ext.spring.SpringFinder">
<lookup-method name="create" bean="studentsResource"/>
</bean>
</entry>
</map>
</property>
</bean>
</property>
</bean>
<!-- spring annotation -->
<context:component-scan base-package="com.xl.sr"/>

八、Client代码

public class StudentClient {
public void student_get() {
try {
ClientResource client = new ClientResource("http://127.0.0.1:8080/SpringRestlet/student/1");
Representation representation = client.get();
System.out.println(representation.getText());
} catch (Exception e) {
e.printStackTrace();
}
}

public void student_delete() {
try {
ClientResource client = new ClientResource("http://127.0.0.1:8080/SpringRestlet/student/1");
Representation representation = client.delete();
System.out.println(representation.getText());
} catch (Exception e) {
e.printStackTrace();
}
}

public void student_put() {
try {
ClientResource client = new ClientResource("http://127.0.0.1:8080/SpringRestlet/student/1");
Student student = new Student("Test_Put", 1, 18);
Representation representation = client.put(student, MediaType.APPLICATION_JAVA_OBJECT);
System.out.println(representation.getText());
} catch (Exception e) {
e.printStackTrace();
}
}

public void student_post() {
try {
ClientResource client = new ClientResource("http://127.0.0.1:8080/SpringRestlet/student");
Student student = new Student("Test_Post", 1, 18);
Representation representation = client.post(student, MediaType.APPLICATION_JAVA_OBJECT);
System.out.println(representation.getText());
} catch (Exception e) {
e.printStackTrace();
}
}

public void student_findAll() {
try {
ClientResource client = new ClientResource("http://127.0.0.1:8080/SpringRestlet/student");
Representation representation = client.get();
System.out.println(representation.getText());
} catch (Exception e) {
e.printStackTrace();
}
}

public static void main(String[] args) {
StudentClient client = new StudentClient();
client.student_get();
}
}

九、补充

    (1)、请求参数问题：客户端发送形如/student/{studentId}的URI请求时，可能是还需要携带其他parameter的，参数携带形式可如/student/{studentId}?name=John&sex=23；Server端获取参数时，针对在URI{}内的参数使用getRequest().getAttributes().get("studentId");方式获取，针对附加参数可以通过Form form = getRequest().getResourceRef().getQueryAsForm();
String name = form.getValues("name");方式获取。

    (2)、客户端工具：测试Server端时，如果不想写Client端code,可以是WizTools.org的RestClient-ui.jar的小工具，Post和Put请求时的对象可以以JSON格式添加到Http body中即可。

    (3)、相关资源：文中工程以上传至51cto下载中心，含代码和Jar包。链接地址:http://download.csdn.net/detail/u013379717/7127389