RESTEASY003940: Unable to instantiate MessageBodyReader

Getting advice
1

I’m getting this error:
java.lang.RuntimeException: RESTEASY003940: Unable to instantiate MessageBodyReader
When I want to access from the resource server to keycloak server

code:

Keycloak keycloak = KeycloakBuilder.builder()
        .serverUrl(serverUrl)
        .realm(realm)
        .grantType(OAuth2Constants.PASSWORD)
        .clientId(clientId)
        .clientSecret(clientSecret)
        .username("user")
        .password("password")
        .resteasyClient(
                new ResteasyClientBuilderImpl()
                    .connectionPoolSize(20)
                    .build()
                )
        .build();

pom.xml

<dependency>
    <groupId>org.keycloak</groupId>
    <artifactId>keycloak-admin-client</artifactId>
    <version>14.0.0</version>
</dependency>   

<dependency>
    <groupId>org.jboss.resteasy</groupId>
    <artifactId>resteasy-client</artifactId>
    <version>4.7.1.Final</version>
</dependency>

<dependency>
    <groupId>org.jboss.resteasy</groupId>
    <artifactId>resteasy-jackson2-provider</artifactId>
    <version>4.7.1.Final</version>
</dependency>

<dependency>
    <groupId>org.jboss.resteasy</groupId>
    <artifactId>resteasy-multipart-provider</artifactId>
    <version>4.7.1.Final</version>
</dependency>

Thanks for your help

2

Might be your resteasy version. Keycloak 14 uses 3.15.1.Final.

1 Like
3

Thanks so much for you help. Now it works