Jersey服務類為介面時出現java.lang.NoSuchMethodException

Jersey服務類為介面時出現java.lang.NoSuchMethodException

在使用Jersey時，把提供服務的類設計為介面，配置在web.xml中，運行Tomcat之後訪問服務出現異常：

java.lang.NoSuchMethodException: Could not find a suitable constructor in coursemanager.resource.CourseResource class.

情景

使用的bean：

package coursemanager.bean;/** * 課程 */public class Course {    /**     * 課程ID     */    private Integer id;    /**     * 課程名稱     */    private String name;    /**     * 教授老師     */    private String teacher;    /**     * 教室地點     */    private String location;    /**     * 學生人數     */    private Integer studentNum;    public Integer getId() {        return id;    }    public void setId(Integer id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public String getTeacher() {        return teacher;    }    public void setTeacher(String teacher) {        this.teacher = teacher;    }    public String getLocation() {        return location;    }    public void setLocation(String location) {        this.location = location;    }    public Integer getStudentNum() {        return studentNum;    }    public void setStudentNum(Integer studentNum) {        this.studentNum = studentNum;    }    public Course() {    }    public Course(String name, String teacher, String location, Integer studentNum) {        super();        this.name = name;        this.teacher = teacher;        this.location = location;        this.studentNum = studentNum;    }    public Course(Integer id, String name, String teacher, String location, Integer studentNum) {        super();        this.id = id;        this.name = name;        this.teacher = teacher;        this.location = location;        this.studentNum = studentNum;    }    @Override    public String toString() {        return "Course [id=" + id + ", name=" + name + ", teacher=" + teacher + ", location=" + location                + ", studentNum=" + studentNum + "]";    }}

聲明服務的介面：

package coursemanager.resource;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.QueryParam;import javax.ws.rs.core.MediaType;import coursemanager.bean.Course;/** * 課程資源 */@Path("course")public interface CourseResource {    /**     * 儲存課程資訊     *     接收json資訊     *     返回課程的資源地址     * @param course 課程     * @return 成功新課程的id,失敗返回"error"     */    @POST    @Consumes(MediaType.APPLICATION_JSON)    @Produces(MediaType.TEXT_PLAIN)    public Integer save(Course course);    /**     * 刪除課程     * @param id 課程ID     * @return 成功返回"success"，失敗返回"error"     */    @DELETE    @Path("{id:\\d+}")    public String delete(@PathParam("id") Integer id);    /**     * 更新課程資訊     * @param course 課程     * @return 成功返回"success"，失敗返回"error"     */    @PUT    @Consumes(MediaType.APPLICATION_JSON)    @Produces(MediaType.TEXT_PLAIN)    public String update(Course course);    /**     * 擷取特定ID的課程資訊     * @param id 課程ID     * @return 課程     */    @GET    @Path("{id:\\d+}")    @Produces(MediaType.APPLICATION_JSON)    public Course get(@PathParam("id") Integer id);    /**     * 通過課程名字查詢課程資訊     * @param name     * @return     */    @GET    @Produces(MediaType.APPLICATION_JSON)    public Course getByCourseName(@QueryParam("name") String name);}

介面的實作類別：

package coursemanager.impl;import java.util.ArrayList;import java.util.Iterator;import java.util.List;import coursemanager.bean.Course;import coursemanager.resource.CourseResource;public class CourseResourceImpl implements CourseResource {    public static Integer courseId = 0;    public static List<Course> courses = new ArrayList<Course>();    public CourseResourceImpl() {        System.out.println("初始化5條記錄");        // 添加5個記錄        for (int i = 1; i <= 5; i++) {            Course course = new Course("課程" + i, "教師" + i, "地點" + i, 50);            addCourse(course);        }    }    @Override    public Integer save(Course course) {        addCourse(course);        return course.getId();    }    @Override    public String delete(Integer id) {        Iterator<Course> iter = courses.iterator();        while (iter.hasNext()) {            Course course = iter.next();            if (course.getId().equals(id)) {                courses.remove(course);                courseId--;                return "success";            }        }        return "error";    }    @Override    public String update(Course course) {        Iterator<Course> iter = courses.iterator();        while (iter.hasNext()) {            Course co = iter.next();            if (co.getId().equals(course.getId())) {                courses.remove(co);                courses.add(course);                return "success";            }        }        return "error";    }    @Override    public Course get(Integer id) {        Iterator<Course> iter = courses.iterator();        while (iter.hasNext()) {            Course course = iter.next();            if (course.getId().equals(id)) {                return course;            }        }        return null;    }    @Override    public Course getByCourseName(String name) {        Iterator<Course> iter = courses.iterator();        while (iter.hasNext()) {            Course course = iter.next();            if (course.getName().equals(name)) {                return course;            }        }        return null;    }    private void addCourse(Course course) {        courseId++;        course.setId(courseId);        courses.add(course);    }}

在web.xml中的配置：

    <servlet>        <servlet-name>Jersey Web Application</servlet-name>        <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>        <init-param>            <param-name>jersey.config.server.provider.packages</param-name>            <param-value>coursemanager</param-value>        </init-param>        <load-on-startup>1</load-on-startup>    </servlet>    <servlet-mapping>        <servlet-name>Jersey Web Application</servlet-name>        <url-pattern>/*</url-pattern>    </servlet-mapping>

訪問http://localhost:8080/coursemanager/course/1，觸發異常

嚴重: Servlet.service() for servlet [Jersey Web Application] in context with path [/coursemanager] threw exception [A MultiException has 1 exceptions.  They are:1. java.lang.NoSuchMethodException: Could not find a suitable constructor in coursemanager.resource.CourseResource class.] with root causejava.lang.NoSuchMethodException: Could not find a suitable constructor in coursemanager.resource.CourseResource class.    at org.glassfish.jersey.internal.inject.JerseyClassAnalyzer.getConstructor(JerseyClassAnalyzer.java:192)    at org.jvnet.hk2.internal.Utilities.getConstructor(Utilities.java:178)    at org.jvnet.hk2.internal.Utilities.justCreate(Utilities.java:988)    at org.jvnet.hk2.internal.ServiceLocatorImpl.create(ServiceLocatorImpl.java:962)    at org.jvnet.hk2.internal.ServiceLocatorImpl.createAndInitialize(ServiceLocatorImpl.java:1054)    at org.jvnet.hk2.internal.ServiceLocatorImpl.createAndInitialize(ServiceLocatorImpl.java:1046)    at org.glassfish.jersey.internal.inject.Injections.getOrCreate(Injections.java:173)    at org.glassfish.jersey.server.model.MethodHandler$ClassBasedMethodHandler.getInstance(MethodHandler.java:284)    at org.glassfish.jersey.server.internal.routing.PushMethodHandlerRouter.apply(PushMethodHandlerRouter.java:74)    at org.glassfish.jersey.server.internal.routing.RoutingStage._apply(RoutingStage.java:109)    at org.glassfish.jersey.server.internal.routing.RoutingStage._apply(RoutingStage.java:112)    at org.glassfish.jersey.server.internal.routing.RoutingStage._apply(RoutingStage.java:112)    at org.glassfish.jersey.server.internal.routing.RoutingStage._apply(RoutingStage.java:112)    at org.glassfish.jersey.server.internal.routing.RoutingStage._apply(RoutingStage.java:112)    at org.glassfish.jersey.server.internal.routing.RoutingStage.apply(RoutingStage.java:92)    at org.glassfish.jersey.server.internal.routing.RoutingStage.apply(RoutingStage.java:61)    at org.glassfish.jersey.process.internal.Stages.process(Stages.java:197)    at org.glassfish.jersey.server.ServerRuntime$2.run(ServerRuntime.java:318)    at org.glassfish.jersey.internal.Errors$1.call(Errors.java:271)    at org.glassfish.jersey.internal.Errors$1.call(Errors.java:267)    at org.glassfish.jersey.internal.Errors.process(Errors.java:315)    at org.glassfish.jersey.internal.Errors.process(Errors.java:297)    at org.glassfish.jersey.internal.Errors.process(Errors.java:267)    at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:317)    at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:305)    at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:1154)    at org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:473)    at org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:427)    at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:388)    at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:341)    at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:228)    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)    at coursemanager.filter.EncodingFilter.doFilter(EncodingFilter.java:36)    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)    at org