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javagraphql-java

NoClassDefFoundError when using SimpleGraphQLServlet.Builder

I wrote a simple GraphQL Servlet based on class SimpleGraphQLServlet. The constructor of this class is deprecated and it is recommended to use the builder instead. So what I did is to provide my own servlet which forwards the requests to an instance of SimpleGraphQLServlet which can be builded in my servlet's init method:

@WebServlet("/graphql")
public class GraphQLEndpoint extends HttpServlet {

    SimpleGraphQLServlet graphQLServlet;

    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        graphQLServlet.service(req, resp);
    }

    @Override
    public void init() throws ServletException {
        graphQLServlet = SimpleGraphQLServlet.builder(buildSchema()).withInstrumentation(new TracingInstrumentation()).build();
    }

    private GraphQLSchema buildSchema() { /* ... */ }
}

However, when the SimpleGraphQLServlet instance is created, the following exception is thrown:

java.lang.NoClassDefFoundError: graphql/execution/instrumentation/NoOpInstrumentation
        at graphql.servlet.SimpleGraphQLServlet$Builder.<init>(SimpleGraphQLServlet.java:134) ~[graphql-java-servlet-4.7.0.jar:na]

which is strange as the class seems to be available in the jar file graphql-java-8.0.jar. I declared the following dependencies:

dependencies {
    compile "com.graphql-java:graphql-java:8.0"
    compile "com.graphql-java:graphql-java-tools:4.3.0"
    compile "com.graphql-java:graphql-java-servlet:4.7.0"

    compile "org.slf4j:slf4j-simple:1.7.25"

    testCompile "junit:junit:3.8.1"
    providedCompile "javax.servlet:javax.servlet-api:3.0.1"
}

What did I miss?

Solution

  • I did receive a hint from @kaqqao who informed me, that my exception is a graphql-java version mismatch. Version 8.0 which I was using is not yet compatible.

    Now I use the following graphql-java dependencies, and it works fine:

    compile "com.graphql-java:graphql-java:7.0"
compile "com.graphql-java:graphql-java-tools:4.3.0"
compile "com.graphql-java:graphql-java-servlet:4.7.0"

    @kaqqao closed with the comment "Overriding dependency versions is scary business.". I agree ;-)