无法在Jersey 2.0中为Jackson启用基于POJO的JSON绑定支持 [英] Can't enable POJO based JSON binding support for Jackson in Jersey 2.0

问题描述

我正在使用Jersey来制作JSON（通过杰克逊的POJO映射）和Jetty（从主方法开始）。

它适用于Jersey 1.x。：

  ServletHolder sh = new ServletHolder（ServletContainer.class）; 
 sh.setInitParameter（com.sun.jersey.config.property.resourceConfigClass，
com.sun.jersey.api.core.PackagesResourceConfig）; 
 sh.setInitParameter（com.sun.jersey.config.property.packages，service）; 
 sh.setInitParameter（com.sun.jersey.api.json.POJOMappingFeature，true）; 
 ... 
 context.addServlet（sh，/ rest / *）; 
服务器服务器=新服务器（8080）; 
 server.setHandler（context）; 
 server.start（）; 
  

现在我将我的项目迁移到Jersey 2.0并且未能在其中启用基于POJO的JSON绑定，我得到了以下内容：
org.glassfish.jersey.message.internal.MessageBodyProviderNotFoundException：找不到媒体类型= application / json的MessageBodyWriter，type = class business.entity.ExampleEntity，genericType = class business。 entity.ExampleEntity。

显然， com.sun.jersey.api.json.POJOMappingFeature 不再有效，因为泽西岛去了 org.glassfish

documentation 说以下内容：

为了使用Jackson作为您的JSON（JAXB / POJO）提供程序，您需要在Configurable（客户端/服务器）中注册JacksonFeature和ObjectMapper的ContextResolver（如果需要）。

但在我的情况下，我无法弄清楚如何正确地做到这一点。

我为这个问题创建了一个小小的项目：

branch master - Jersey 1.17.1的工作示例;

branch jersey-2.0-migration - 没有尝试迁移到Jersey 2.0 - 测试失败;

分支 jersey-2.0-migrate-client-only - 非工作尝试使用Jersey客户端2.0与工作的Jersey服务器1.17.1 - 测试失败。

<强>问题是：如何启用基于JSON POJO在Jersey 2.0结合

解决方案

文档有点过时了。最新的Jackson版本提供了一个可自动发现的提供商。将以下jar添加到类路径中：

1）jackson-annotations-2.2.2.jar

2）jackson-core-2.2.2.jar

3）jackson-databind-2.2.2.jar

4）jackson-jaxrs-base-2.2.1.jar

5）jackson-jaxrs-json-provider-2.2.1.jar

'p> 6）杰克逊模块-JAXB的注解-2.2.2.jar

确认添加com.fasterxml.jackson .jaxrs.json到jersey.config.server.provider.packagesservlet配置属性，因此可以自动发现Jackson json提供程序。

I'm using Jersey to produce JSON (with POJO mapping through Jackson) and Jetty (start from main method).
It works perfect for Jersey 1.x.:

ServletHolder sh = new ServletHolder(ServletContainer.class);
sh.setInitParameter("com.sun.jersey.config.property.resourceConfigClass",
                        "com.sun.jersey.api.core.PackagesResourceConfig");
sh.setInitParameter("com.sun.jersey.config.property.packages", "service");
sh.setInitParameter("com.sun.jersey.api.json.POJOMappingFeature", "true");
...
context.addServlet(sh, "/rest/*");
Server server = new Server(8080);
server.setHandler(context);
server.start();

Now I migrated my project to Jersey 2.0 and failed to enable POJO based JSON binding in it, I get the following: org.glassfish.jersey.message.internal.MessageBodyProviderNotFoundException: MessageBodyWriter not found for media type=application/json, type=class business.entity.ExampleEntity, genericType=class business.entity.ExampleEntity.

Obviously, com.sun.jersey.api.json.POJOMappingFeature no longer valid as Jersey goes to org.glassfish

The documentation say the following:

In order to use Jackson as your JSON (JAXB/POJO) provider you need to register JacksonFeature and a ContextResolver for ObjectMapper (if needed) in your Configurable (client/server).

But I can't figure out how to do it correctly in my case.

I created a little project for this question:

branch master - worked example for Jersey 1.17.1;

branch jersey-2.0-migration - not working attempt to migrate to Jersey 2.0 - test failed;

branch jersey-2.0-migrate-client-only - non working attempt to use Jersey client 2.0 with working Jersey server 1.17.1 - test failed.

Question is: how to enable POJO based JSON binding in Jersey 2.0

解决方案

The documentation is a bit outdated. The latest Jackson build provides an auto-discoverable provider. Add the following jars to the class path:

1) jackson-annotations-2.2.2.jar

2) jackson-core-2.2.2.jar

3) jackson-databind-2.2.2.jar

4) jackson-jaxrs-base-2.2.1.jar

5) jackson-jaxrs-json-provider-2.2.1.jar

6) jackson-module-jaxb-annotations-2.2.2.jar

Make sure to add "com.fasterxml.jackson.jaxrs.json" to the "jersey.config.server.provider.packages" servlet config property, so the Jackson json provider can be auto-discovered.

这篇关于无法在Jersey 2.0中为Jackson启用基于POJO的JSON绑定支持的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！