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如何定义在JEE中处理多部分数据的JAX-RS服务？

问题内容：

这是我到目前为止所拥有的：

这将初始化我的REST服务

package com.dothatapp.web.rest;

import javax.servlet.annotation.MultipartConfig;
import javax.ws.rs.ApplicationPath;
import javax.ws.rs.core.Application;

@ApplicationPath("/authed/rest")
public class JaxRsActivator extends Application {
}

我的服务如下所示：

import javax.servlet.http.HttpServletRequest;
import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.UriInfo;

import org.json.JSONObject;

@Path("fileupload")
public class FileUpload {

    @Context
    private UriInfo context;

    @POST
    @Consumes(MediaType.MULTIPART_FORM_DATA)
    @Produces(MediaType.APPLICATION_JSON)
    public JSONObject doUpload(@Context HttpServletRequest obj) {
        try {
            obj.getParts();
        } catch (Exception e) {
            e.printStackTrace();
        } 
        System.out.println(us);
        System.out.println(es);
        System.out.println(obj);
        return null;
    }
}

我尝试将添加@MultipartConfig到中JaxRsActivator，但仍然出现异常：
在没有多部分配置的情况下调用Request.getParts。
在servlet中添加@MultipartConfig或在web.xml中添加multipart-config元素
。

3-12-08T17:03:05.013+0000|SEVERE: java.lang.IllegalStateException: Request.getParts is called without multipart configuration. Either add a @MultipartConfig to the servlet, or a multipart-config element to web.xml
    at org.apache.catalina.connector.Request.checkMultipartConfiguration(Request.java:4522)
    at org.apache.catalina.connector.Request.getParts(Request.java:4528)
    at org.apache.catalina.connector.RequestFacade.getParts(RequestFacade.java:1086)
    at com.dothatapp.web.rest.FileUpload.doUpload(FileUpload.java:36)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.glassfish.jersey.server.model.internal.ResourceMethodInvocationHandlerFactory$1.invoke(ResourceMethodInvocationHandlerFactory.java:81)
    at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.invoke(AbstractJavaResourceMethodDispatcher.java:125)
    at org.glassfish.jersey.server.model.internal.JavaResourceMethodDispatcherProvider$TypeOutInvoker.doDispatch(JavaResourceMethodDispatcherProvider.java:195)
    at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.dispatch(AbstractJavaResourceMethodDispatcher.java:91)
    at org.glassfish.jersey.server.model.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:346)
    at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:341)
    at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:101)
    at org.glassfish.jersey.server.ServerRuntime$1.run(ServerRuntime.java:224)
    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:198)
    at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:946)
    at org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:323)
    at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:372)
    at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:335)
    at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:218)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:344)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
    at com.dothatapp.web.filter.DoThatAppFilter.doFilter(DoThatAppFilter.java:27)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
    at com.dothatapp.web.filter.AuthFilter.doFilter(AuthFilter.java:113)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:316)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:357)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:260)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:188)
    at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191)
    at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168)
    at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189)
    at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114)
    at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
    at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838)
    at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544)
    at java.lang.Thread.run(Thread.java:724)

谢谢


问题答案：

最终，我在没有Jersey耦合的情况下设法解决了这一问题。问题是@Multipart注释不能与一起使用Application，因此您需要在web.xml内定义它，而在Application类内定义提供的服务。在服务内部，您可以正常使用注释。另请注意，我正在Parts从请求中提取，但这很容易。

PS。实际上，这实现了bluimp JQuery文件上传的后端

web.xml

<servlet>
    <servlet-name>com.web.rest.JaxRsActivator</servlet-name>
    <multipart-config>
        <location>c:\dotmp</location>
        <max-file-size>35000000</max-file-size>
        <max-request-size>218018841</max-request-size>
        <file-size-threshold>0</file-size-threshold>
    </multipart-config>
</servlet>
<servlet-mapping>
    <servlet-name>com.dothatapp.web.rest.JaxRsActivator</servlet-name>
    <url-pattern>/rest/*</url-pattern>
</servlet-mapping>

JaxRsActivator.java

    import java.util.HashSet;
    import java.util.Set;

    import javax.ws.rs.core.Application;

    public class JaxRsActivator extends Application {
          @Override
            public Set<Class<?>> getClasses() {
                Set<Class<?>> s = new HashSet<Class<?>>();
                s.add(FileUpload.class);
                return s;
            }
    }

FileUpload.java

import java.io.IOException;

import javax.json.Json;
import javax.json.JsonArrayBuilder;
import javax.json.JsonObject;
import javax.json.JsonObjectBuilder;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.Part;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

@Path("/")
public class FileUpload {

    @POST
    @Produces(MediaType.APPLICATION_JSON)
    @Path("fileupload")
    public Response doUpload(@Context HttpServletRequest request) {
        JsonArrayBuilder array = Json.createArrayBuilder();

        try {
            for (Part part : request.getParts()) {
                String name = null;
                long size = 0;
                try {
                    if (part.getContentType() == null
                            || !part.getContentType().toLowerCase()
                                    .startsWith("image/"))
                        continue;

                    name = part.getSubmittedFileName();
                    size = part.getSize();

                    array.add(addFile(name, size, "anId"));
                    part.delete();
                } catch (Exception e) {
                    array.add(addError(name, size, "ERROR"));
                }
            }
        } catch (IOException | ServletException e) {
            e.printStackTrace();
        }

        JsonObject ret = Json.createObjectBuilder().add("files", array).build();
        return Response.status(201).entity(ret).build();
    }

    private JsonObjectBuilder addFile(String name, long size, String url) {
        return Json.createObjectBuilder().add("name", name).add("size", size)
                .add("lid", url);
    }

    private JsonObjectBuilder addError(String name, long size, String error) {
        return Json.createObjectBuilder().add("name", name).add("size", size)
                .add("error", error);
    }

}