javax.ws.rs.ProcessingException: could not find writer for content-type application/json

Question

I am new to REST web services. Am trying @post and @consumes annotation as below

@POST
@Path("/post")
@Consumes("application/json")
public Response createProductInJSON(Product product) {
    String result = "Product created : " + product;
    return Response.status(201).entity(result).build();
}

Edit Product Class

public class Product {
    String name;
    int qty;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getQty() {
        return qty;
    }

    public void setQty(int qty) {
        this.qty = qty;
    }
}

Now I want to test this, so am using the below code to test.

Product product=new Product();
    product.setName("windows_phone");
    product.setQty(4);

    ResteasyClient client = new ResteasyClientBuilder().build();
    ResteasyWebTarget target = client.target("http://localhost:8080/Rest_Services/practice/service/post");

    Response response = target.request().post(Entity.entity(product, "application/json"));

    if (response.getStatus() != 200) {
        throw new RuntimeException("Failed : HTTP error code : "+ response.getStatus());
    }

    System.out.println("Server response : \n");
    System.out.println(response.readEntity(String.class));
    response.close();

Am getting the below error when executed.

log4j:WARN No appenders could be found for logger (org.jboss.resteasy.plugins.providers.DocumentProvider).
log4j:WARN Please initialize the log4j system properly.
Exception in thread "main" javax.ws.rs.ProcessingException: Unable to invoke request
at org.jboss.resteasy.client.jaxrs.engines.ApacheHttpClient4Engine.invoke(ApacheHttpClient4Engine.java:287)

Caused by: javax.ws.rs.ProcessingException: could not find writer for content-type application/json type: com.model.Product
at org.jboss.resteasy.core.interception.ClientWriterInterceptorContext.throwWriterNotFoundException(ClientWriterInterceptorContext.java:40)
at org.jboss.resteasy.core.interception.AbstractWriterInterceptorContext.getWriter(AbstractWriterInterceptorContext.java:138)

Below are the Jars am using.

EDIT 3 POM.XML

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

<modelVersion>4.0.0</modelVersion>
<groupId>rest_maven</groupId>
<artifactId>rest_maven</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<build>
<sourceDirectory>src</sourceDirectory>
<plugins>
  <plugin>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.0</version>
    <configuration>
      <source>1.7</source>
      <target>1.7</target>
    </configuration>
  </plugin>
  <plugin>
    <artifactId>maven-war-plugin</artifactId>
    <version>2.3</version>
    <configuration>
      <warSourceDirectory>WebContent</warSourceDirectory>
      <failOnMissingWebXml>false</failOnMissingWebXml>
    </configuration>
  </plugin>
</plugins>
</build>
<dependencies>
    <dependency>
        <groupId>org.glassfish.jersey.core</groupId>
        <artifactId>jersey-server</artifactId>
        <version>2.6</version>
    </dependency>
    <dependency>
        <groupId>org.glassfish.jersey.containers</groupId>
        <artifactId>jersey-container-servlet-core</artifactId>
        <version>2.6</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>1.5.6</version>
    </dependency>
    <dependency>
        <groupId>com.google.code.gson</groupId>
        <artifactId>gson</artifactId>
        <version>2.3.1</version>
    </dependency>
    <dependency>
        <groupId>commons-logging</groupId>
        <artifactId>commons-logging</artifactId>
        <version>1.1.3</version>
    </dependency>
    <dependency>
        <groupId>commons-io</groupId>
        <artifactId>commons-io</artifactId>
        <version>2.2</version>
    </dependency>
    <dependency>
        <groupId>commons-codec</groupId>
        <artifactId>commons-codec</artifactId>
        <version>1.9</version>
    </dependency>
    <dependency>
        <groupId>javax.activation</groupId>
        <artifactId>activation</artifactId>
        <version>1.1.1</version>
    </dependency>
    <dependency>
        <groupId>org.apache.httpcomponents</groupId>
        <artifactId>httpclient</artifactId>
        <version>4.3.6</version>
    </dependency>
    <dependency>
        <groupId>org.apache.httpcomponents</groupId>
        <artifactId>httpcore</artifactId>
        <version>4.3.3</version>
    </dependency>
    <dependency>
        <groupId>org.jboss.spec.javax.annotation</groupId>
        <artifactId>jboss-annotations-api_1.1_spec</artifactId>
        <version>1.0.1.Final</version>
    </dependency>
    <dependency>
        <groupId>net.jcip</groupId>
        <artifactId>jcip-annotations</artifactId>
        <version>1.0</version>
    </dependency>
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.14</version>
    </dependency>
    <dependency>
        <groupId>org.glassfish.jersey.media</groupId>
        <artifactId>jersey-media-moxy</artifactId>
        <version>2.6</version>
    </dependency>
    <dependency>
        <groupId>org.jboss.resteasy</groupId>
        <artifactId>resteasy-client</artifactId>
        <version>3.0.12.Final</version>
    </dependency>
    <dependency>
        <groupId>org.jboss.resteasy</groupId>
        <artifactId>resteasy-jaxrs</artifactId>
        <version>3.0.12.Final</version>
    </dependency>
    <dependency>
        <groupId>org.jboss.resteasy</groupId>
        <artifactId>jaxrs-api</artifactId>
        <version>3.0.12.Final</version>
    </dependency>
    <dependency>
        <groupId>org.jboss.resteasy</groupId>
        <artifactId>resteasy-jaxb-provider</artifactId>
        <version>3.0.12.Final</version>
    </dependency>
    <dependency>
        <groupId>org.jboss.resteasy</groupId>
        <artifactId>resteasy-jackson2-provider</artifactId>
        <version>3.0.12.Final</version>
    </dependency>
</dependencies>
</project>

settings.xml

<settings>
<localRepository>Z:\PROD_Deploy\mvn\repository</localRepository>

<proxies>
<proxy>
  <active>true</active>
  <protocol>http</protocol>
  <username>xxx</username>
  <password>xxx</password>
  <host>xxx</host>
  <port>80</port>
  <nonProxyHosts>local.net|some.host.com</nonProxyHosts>
</proxy>

Please help me get through this error. Thanks in advance.

Answer 1

So, after looking up on JBoss docs I think I've found your issue:

You're using resteasy-client-3.0.4.Final which depends on resteasy-jaxrs-3.0.4.Final, as stated here.

Now the thing is, on resteasy-jaxrs-3.0.4.Final the class CaseInsensitiveMap<V> has a different hierarchy than the one of resteasy-jaxrs-3.0.12.Final.

My suggestion is for you to upgrade your resteasy-client for the version 3.0.12.

EDIT

Your pom.xml should include these dependencies. Validate which ones you don't have and update your Maven project:

<dependency>
    <groupId>org.jboss.resteasy</groupId>
    <artifactId>resteasy-jaxrs</artifactId>
    <version>3.0.12.Final</version>
</dependency>

<dependency>
    <groupId>org.jboss.resteasy</groupId>
    <artifactId>jaxrs-api</artifactId>
    <version>3.0.12.Final</version>
</dependency>

<dependency>
    <groupId>org.jboss.resteasy</groupId>
    <artifactId>resteasy-jaxb-provider</artifactId>
    <version>3.0.12.Final</version>
</dependency>

<dependency>
    <groupId>org.jboss.resteasy</groupId>
    <artifactId>resteasy-jackson2-provider</artifactId>
    <version>3.0.12.Final</version>
</dependency>