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jsonintellij-ideajava-8objectmapper

IntelliJIdea: red line on a code snippet with error "cannot access org.codehaus.jackson.ObjectCodec"

Preface:

API method (import org.codehaus.jackson.map.ObjectMapper;)

@SuppressWarnings("unchecked")
public <T> T readValue(JsonParser jp, Class<T> valueType) throws IOException, JsonParseException, JsonMappingException
{
    // !!! TODO
    //  _setupClassLoaderForDeserialization(valueType);
    return (T) _readValue(copyDeserializationConfig(), jp, _typeFactory.constructType(valueType));
}

The ObjectMapper class has the readValue method above.

My custom class method (below) is working fine with no errors, but I see a "red Line" for the code line mapper.readValue(UserJson, in IntelliJ Idea...

private User serializeFromJsonString(String UserJson) throws Exception {
    ObjectMapper mapper = new ObjectMapper();
    return mapper.readValue(UserJson, User.class);
}

An example with photo:

intelliJ Idea red line_error

Solution

  • Thank you Stephan, LazerBass.. the "(File -> Invalidate caches)" didn't seem to work, I already tried it yesterday before I posted this Qn in stackOverflow.

    The error didn't appear today.. Seems IDE overlooked into my dependencies..

    Below dependency version is hardcoded in my Spring-boot application. 

    <!-- https://mvnrepository.com/artifact/org.codehaus.jackson/jackson-mapper-asl -->
<dependency>
    <groupId>org.codehaus.jackson</groupId>
    <artifactId>jackson-mapper-asl</artifactId>
    <version>1.9.4</version>
</dependency>

    When I load a Maven project into IntelliJ Idea, it will ask to manually import the dependencies and for this "ObjectMapper" class, the IDE imported a 1.9.12 version of jackson-mapper-asl(in theory it has to take my 1.9.4 version hardcoded in my project). So I went and add additional 1.9.4 jar which is irrelevant, but just thought to check.

    I did some more research and checked the "readValue" method of ObjectMapper class in all the versions(link: https://mvnrepository.com/artifact/org.codehaus.jackson/jackson-mapper-asl) and surprisingly all the versions of this jackson-mapper-asl jar has this method in it.

    Narrowing down, the issue seems to be with intelliJ Idea, ref: https://intellij-support.jetbrains.com/hc/en-us/community/posts/207108385-IntelliJ-not-able-to-resolve-classes-of-external-Libraries-for-Maven-projects