Struts2 REST 插件：通过 PUT 发送 JSON 对象

Question

我正在使用 Struts2 和 Struts2 REST 插件编写一个 RESTful 服务。目前，我的服务能够毫无问题地处理 GET 请求，但我一直试图让它“更新”（PUT）请求工作。

我有两个可能的模型，一个用于 show() 的 List 和一个用于 update() 的 ClientFeature 对象，其中 ClientFeature 是一个 pojo 类。

REST 控制器：

public class ClientfeatureController extends ControllerParent implements ModelDriven<Object> {

    private ClientFeature clientFeature = new ClientFeature();
    private List<ClientFeature> clientFeatureList;

    //Client ID
    private String id;

    public ClientfeatureController() {
        super(ClientfeatureController.class);
    }

    @Override
    public Object getModel() {
        return (clientFeatureList != null ? clientFeatureList : clientFeature);
    }

    /**
     * @return clientFeatureList through Struts2 model-driven design
     */
    public HttpHeaders show() {
        -logic for GET request here..-
        //todo: add ETag and lastModified information for client caching purposes
        return new DefaultHttpHeaders("show").disableCaching();
    }

    // PUT request: /clientfeature/update/<id> + JSON data
    public String update() {
        logger.info("client id: " + id);
        logger.info("updated model test:" + clientFeature.getClientId());
        return "update";
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public List<ClientFeature> getClientFeatureList() {
        return clientFeatureList;
    }

    public void setClientFeatureList(List<ClientFeature> clientFeatureList) {
        this.clientFeatureList = clientFeatureList;
    }
}

客户端功能：

    public class ClientFeature {
    private Long clientId;
    private Feature feature;
    private ArrayList<String> countries;

    public ClientFeature() {
        this.countries = new ArrayList<String>();
    }

    public Long getClientId() {
        return clientId;
    }

    public void setClientId(Long clientId) {
        this.clientId = clientId;
    }

    public Feature getFeature() {
        return feature;
    }

    public void setFeature(Feature feature) {
        this.feature = feature;
    }

    public ArrayList<String> getCountries() {
        return countries;
    }

    public void setCountries(ArrayList<String> countries) {
        this.countries = countries;
    }
}

并且正在使用 chrome 的 Postman 扩展测试该服务，并发送类似于以下内容的 JSON 数据：

{
 "clientFeature": {
   "feature" : {"featureId" : 999, "featureName" : "testFeature"}
   "countries": ["CA","US"]
   "clientId" : 001
 }
}

还有错误：

356572 [http-bio-8080-exec-6] WARN  net.sf.json.JSONObject  - Tried to assign property clientFeature:java.lang.Object to bean of class com.foo.bar.ClientFeature

我对所有相关的东西都非常陌生，因此非常感谢任何帮助。

编辑：

尝试发送以下 JSON：

{ “com.foo.entity.clientFeature”：{“clientId”：10} }

并得到以下完整错误：

1016894 [http-bio-8080-exec-3] ERROR freemarker.runtime  - Method public java.lang.String org.apache.commons.lang.exception.NestableRuntimeException.getMessage(int) threw an exception when invoked on net.sf.json.JSONException: Error while setting property=com.foo.entity.clientFeature type class java.lang.Object

Method public java.lang.String org.apache.commons.lang.exception.NestableRuntimeException.getMessage(int) threw an exception when invoked on net.sf.json.JSONException: Error while setting property=com.foo.entity.clientFeature type class java.lang.Object
The problematic instruction:
----------
==> ${msg[0]} [on line 68, column 29 in org/apache/struts2/dispatcher/error.ftl]
----------

Java backtrace for programmers:
----------
freemarker.template.TemplateModelException: Method public java.lang.String org.apache.commons.lang.exception.NestableRuntimeException.getMessage(int) threw an exception when invoked on net.sf.json.JSONException: Error while setting property=com.foo.entity.clientFeature type class java.lang.Object
    at freemarker.ext.beans.SimpleMethodModel.exec(SimpleMethodModel.java:130)
    at freemarker.ext.beans.SimpleMethodModel.get(SimpleMethodModel.java:138)
    at freemarker.core.DynamicKeyName.dealWithNumericalKey(DynamicKeyName.java:111)
    at freemarker.core.DynamicKeyName._getAsTemplateModel(DynamicKeyName.java:90)
    at freemarker.core.Expression.getAsTemplateModel(Expression.java:89)
    at freemarker.core.Expression.getStringValue(Expression.java:93)
    at freemarker.core.DollarVariable.accept(DollarVariable.java:76)
    at freemarker.core.Environment.visit(Environment.java:210)
    at freemarker.core.MixedContent.accept(MixedContent.java:92)
    at freemarker.core.Environment.visit(Environment.java:210)
    at freemarker.core.IfBlock.accept(IfBlock.java:82)
    at freemarker.core.Environment.visit(Environment.java:210)
    at freemarker.core.IteratorBlock$Context.runLoop(IteratorBlock.java:179)
    at freemarker.core.Environment.visit(Environment.java:417)
    at freemarker.core.IteratorBlock.accept(IteratorBlock.java:102)
    at freemarker.core.Environment.visit(Environment.java:210)
    at freemarker.core.MixedContent.accept(MixedContent.java:92)
    at freemarker.core.Environment.visit(Environment.java:210)
    at freemarker.core.IfBlock.accept(IfBlock.java:82)
    at freemarker.core.Environment.visit(Environment.java:210)
    at freemarker.core.MixedContent.accept(MixedContent.java:92)
    at freemarker.core.Environment.visit(Environment.java:210)
    at freemarker.core.Environment.process(Environment.java:190)
    at freemarker.template.Template.process(Template.java:237)
    at org.apache.struts2.dispatcher.Dispatcher.sendError(Dispatcher.java:797)
    at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:519)
    at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
    at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:224)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:851)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:278)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:300)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
    at java.lang.Thread.run(Thread.java:680)
Caused by: java.lang.NullPointerException
    at freemarker.ext.beans.SimpleMemberModel.unwrapArguments(SimpleMemberModel.java:85)
    at freemarker.ext.beans.SimpleMethodModel.exec(SimpleMethodModel.java:106)
    ... 43 more

Answer 1

通过使用正确的 JSON 语法解决了问题..

如果有人遇到类似问题，在我的情况下，正确的语法是：

{clientFeature: {"feature":{"id":3,"enabled":true,"description":"description here","type":"FEATURE_TYPE_HERE"},"countries":["SG"],"clientId":10}}

Answer 2

我想解释一下我在使用 Strtus2 rest 插件开发 API 时发现了什么。你应该了解 rest 插件如何管理我们暴露给外部世界的 bean（json、xml 等）

我已经坚持了一天来弄清楚我的 json 波纹管如何无法正确转换为我的 bean 列表。

所以，这是我的 json 字符串：

{ 
"messagesList": [{
    "id": "E57EC40F",
    "body": "Ok!",
    ... other_property
},{
    "id": "25B42CC8CCE57EC40F",
    "body": "Testing",
    ... other_property
}],
"ackList": [{
    "id": "5B42CC8CCE57EC40F",
    "queueNumber": 100,
    "chatId": "3434",
    "status": "delivered"
},{
    "id": "E6A25B42CC8CCE57EC40F",
    "queueNumber": 100,
    "chatId": "1747",
    "status": "viewed"
}]
}

有了这个 json，我假设我可以通过添加属性获取并自动将这个 json 转换到我的列表中

 List<OurModel> messageList;
 List<OurModel> ack;

在我的控制器中。所以我的错误控制器看起来像这样：

@ParentPackage("api-pesan")
@Namespace("/api/pesan")
    public class RetrieveMessageApi implements ModelDriven<Object> {
    @Autowired
    WebHookService webHookService;

    Object retModal;
    List<OurModel> messagesList;
    List<OurModel> ack;
    public HttpHeaders create() throws IOException {

        System.out.println(messagesList.toString());

        System.out.println(ack.toString());

        return new DefaultHttpHeaders("create");
    }


    public Object getModel() {
        return model;
    }

//setter and getter

 }

如果你假设你可以在 create 方法中打印 messagesList 和 ack 属性，那你就错了。我被困了一天才能弄清楚。这是我关于如何将 json 发布到我们的 strtus2 REST 插件的解释。

首先，struts2中的rest插件在检索对象并将对象返回到外部restful url时，只读取对象（属性名，也是对象作为类型）。

到那时，我创建了我的类 (pojo) 来包装我的列表。这个类是这样的

public class WrapperModel implements Serializable {

    private List<YourObject> messages;
    private List<YourObject> ack;

//setter getter

}

你会注意到，我们的 json 结构看起来和这个类一样。所以这是我完整且成功的控制器类，它可以获取 json 并正确绑定到我们的属性。

@ParentPackage("api-pesan")
public class RetrieveMessageApi implements ModelDriven<Object> {

    @Autowired
    WebHookService webHookService;

    Object model = new WrapperModel();

    public HttpHeaders create() throws IOException {

        System.out.println(model.toString());


        return new DefaultHttpHeaders("create");
    }



    public Object getModel() {
        return model;
    }

}

然后尝试通过http://localhost:8080/app/api/api-pesan/retrieve-message.json 和方法 post 发送 json，也可以将您的 json 作为正文。

结果，您将在日志控制台上看到来自我们的 json 的属性中的列表字符串。

谢谢，希望对大家有所帮助....