Use Provided jax-rs 2.0 and Jersey 2.1x in Weblogic 12c (12.2.1.3)

I need to implement a rest service call in my WEB application. According to Oracle, Weblogic is supported and does not need to register (deploy) jax-rs, so I would like to use these Server libraries. I made a simple class by calling a service (get). I configured the dependencies in the project and deployed it on Weblogic. However, when deploying, the following error appears: java.lang.ClassCastException: Cannot cast org.glassfish.jersey.ext.cdi1x.internal.CdiComponentProvider to org.glassfish.jersey.server.spi.ComponentProvider

Note: It worked using this link below (deploying the jar on the server) But I want to use the native libraries on Weblogic. Could someone help me please?

https://docs.oracle.com/middleware/1213/wls/RESTF/use-jersey20-ri.htm#RESTF297

Code example (Java)
		String host = "https://swapi.dev/api/people/2/";
		Client client = ClientBuilder.newBuilder().build();
		WebTarget webTarget = client.target(host);
		Builder builder = webTarget.request(MediaType.APPLICATION_JSON);
		String result =  builder.get(String.class);


pom.xml

	<properties>
		<primefaces.version>3.5.RC1</primefaces.version>
        <jersey.version>2.21.1</jersey.version>
        <jaxrs.version>2.0</jaxrs.version>		
	</properties>
    <!-- JAX-RS -->
    <dependency>
        <groupId>javax.ws.rs</groupId>
        <artifactId>javax.ws.rs-api</artifactId>
        <version>${jaxrs.version}</version>
        <scope>provided</scope>
    </dependency>
    <!-- Jersey 2.21.1 -->
    <dependency>
        <groupId>org.glassfish.jersey.containers</groupId>
        <artifactId>jersey-container-servlet</artifactId>
        <version>${jersey.version}</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.glassfish.jersey.core</groupId>
        <artifactId>jersey-server</artifactId>
        <version>${jersey.version}</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.glassfish.jersey.core</groupId>
        <artifactId>jersey-client</artifactId>
        <version>${jersey.version}</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.glassfish.jersey.media</groupId>
        <artifactId>jersey-media-multipart</artifactId>
        <version>${jersey.version}</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.jaxrs</groupId>
        <artifactId>jackson-jaxrs-json-provider</artifactId>
        <version>2.4.1</version>
        <scope>provided</scope>
    </dependency>	
	<dependency>
	  <groupId>com.google.code.gson</groupId>
	  <artifactId>gson</artifactId>
	  <version>2.8.6</version>
	</dependency>



 weblogic.xml

 	<wls:weblogic-version>12.2.1.3</wls:weblogic-version>
    
    <wls:context-root>RecebimentoMercadoriaWEB</wls:context-root>

	<wls:library-ref>
		<wls:library-name>jsf</wls:library-name>
	</wls:library-ref>

    <wls:container-descriptor>
		<wls:prefer-web-inf-classes>true</wls:prefer-web-inf-classes>
	</wls:container-descriptor>
	
    <wls:session-descriptor>
        <wls:cookie-name>CookieRecebimentoMercadoria</wls:cookie-name>
    </wls:session-descriptor>
    
	<wls:container-descriptor>
		<wls:prefer-application-packages>
			<wls:package-name>javax.faces.*</wls:package-name>
			<wls:package-name>com.sun.faces.*</wls:package-name>
			<wls:package-name>com.sun.facelets.*</wls:package-name>
			<wls:package-name>com.bea.faces.*</wls:package-name>
		</wls:prefer-application-packages>

		<wls:prefer-application-resources>
			<wls:resource-name>javax.faces.*</wls:resource-name>
			<wls:resource-name>com.sun.faces.*</wls:resource-name>
			<wls:resource-name>com.sun.facelets.*</wls:resource-name>
			<wls:resource-name>com.bea.faces.*</wls:resource-name>
			<wls:resource-name>META-INF/services/javax.servlet.ServletContainerInitializer</wls:resource-name>
			<wls:resource-name>META-INF/services/com.sun.faces.spi.FacesConfigResourceProvider</wls:resource-name>
		</wls:prefer-application-resources>
	</wls:container-descriptor>

On Weblogic 12.2.1.3 yo do not need to execute the procedure described by the link you have pointed, I mean the link below .

https://docs.oracle.com/middleware/1213/wls/RESTF/use-jersey20-ri.htm#RESTF297

This is because that link belongs to Oracle Weblogic 12.1.3 and there are several differences between Weblogic 12.1.3.0 and Weblogic 12.2.1.3.

Furthermore, this document for Oracle Weblogic 12.2.1.3 states.

> Note:
>
> Jersey 2.x (JAX-RS 2.0 RI) support is provided by default in this
> release of WebLogic Server. Registration as a shared library is no
> longer required.

This means, when it comes to Weblogic 12.2.1.3 Jersey libraries are in place and ready to be used. Thus, your application should be able to use them.

However, I think server libraries are getting troubles with the libraries you are using within your pom.xml file.

Furthermore Oracle Weblogic 12.2.1.3 provides jersey 2.22.4

I have also used wls-cat in one of my servers to know, which library is loading the class org.glassfish.jersey.ext.cdi1x.internal.CdiComponentProvider and I have found the library in $ORACLE_HOME/oracle_common/modules/org.glassfish.jersey.ext.cdi.jersey-cdi1x.jar, which means it is loaded by Weblogic as is stated on above documentation.

Furthermore, after running wls-cat I can see this:

org.glassfish.jersey.ext.cdi1x.internal.CdiComponentProvider implements org.glassfish.jersey.server.spi.ComponentProvider

Thus, cast should not be an issue, which means there is a class loading problem that most probably is caused by libraries included in your application.

You can see the results of wls-cat executed on my server on below picture

You can use wls-cat to see which file (a JAR library) is loading the conflicting class. In below post you will find information about how to use wls-cat to analyse class loading problems.

https://blog.sysco.no/class/loader/AnalysingClassLoadingConflicts/

The libraries were really conflicting. I removed these dependencies from pom.xml and it worked. Thanks for the tip.

    <dependency>
        <groupId>org.glassfish.jersey.core</groupId>
        <artifactId>jersey-server</artifactId>
        <version>${jersey.version}</version>
        <scope>provided</scope>
    </dependency>
   
	<dependency>
        <groupId>org.glassfish.jersey.containers</groupId>
        <artifactId>jersey-container-servlet</artifactId>
        <version>${jersey.version}</version>
        <scope>provided</scope>
    </dependency>

   <dependency>
        <groupId>org.glassfish.jersey.media</groupId>
        <artifactId>jersey-media-multipart</artifactId>
        <version>${jersey.version}</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.jaxrs</groupId>
        <artifactId>jackson-jaxrs-json-provider</artifactId>
        <version>2.4.1</version>
        <scope>provided</scope>
    </dependency>