[FIXED] NoSuchMethodError Exception causing service to not receive subsequent REST calls

Issue

I'm facing this issue for the first time, here's the exception that gets thrown in the service

Exception in thread "Thread-1" java.lang.NoSuchMethodError: org.codehaus.jackson.type.JavaType.<init>(Ljava/lang/Class;)V
    at org.codehaus.jackson.map.type.TypeBase.<init>(TypeBase.java:13)
    at org.codehaus.jackson.map.type.SimpleType.<init>(SimpleType.java:45)
    at org.codehaus.jackson.map.type.SimpleType.<init>(SimpleType.java:40)
    at org.codehaus.jackson.map.type.TypeFactory._fromClass(TypeFactory.java:374)
    at org.codehaus.jackson.map.type.TypeFactory._fromType(TypeFactory.java:434)
    at org.codehaus.jackson.map.type.TypeFactory.type(TypeFactory.java:61)
    at org.codehaus.jackson.map.ObjectMapper.<clinit>(ObjectMapper.java:174)
    at com.kx.proto.validation.util.Common.<clinit>(Common.java:41)

and once this exception is thrown, the service stops receiving the subsequent api calls made to the service ( even though i have caught the exception ) , pod is still in running state. I'm curious about two things here

1. The exception that gets thrown, how to fix that ? Change in POM file?
2. Why would the exception that has been caught would stop service from receiving further REST api calls. Basically after the exception , all the apis in service start timing out.

Below is the piece of code where exception gets thrown

at this line

        GeneratedMessageV3 messageV3 = Common.loadDefaultObjectFromMessage("com.kx.proto.", recordId.toUpperCase() + "Record");

and here's the loadDefaultObject from message method

  public static GeneratedMessageV3 loadDefaultObjectFromMessage(String pkg, String messageName) {
        try {
            Class<?> record = Class.forName(pkg + messageName);
            Optional<Method> getDefaultInstance = Arrays.asList(record.getDeclaredMethods()).stream().filter((method) -> {
                return method.getName().equals("getDefaultInstance");
            }).findFirst();
            if (getDefaultInstance.isPresent()) {
                Object obj = ((Method)getDefaultInstance.get()).invoke((Object)null, (Object[])null);
                return (GeneratedMessageV3)obj;
            }
        } catch (ClassNotFoundException var5) {
            System.out.println("class not found " + var5.getMessage());
        } catch (Exception var6) {
            var6.printStackTrace();
        }

        return null;
    }

Solution

NoSuchMethodError is an Error (not an Exception) that occurs when the classpath during compilation differs from the classpath at runtime.

It says: I could find that method during compilation, but I can't find that method now at runtime.

It typically occurs when the runtime classpath differs from the compilation classpath. This gets more complex if your project A depends on jar B which depends on jar C. Presume all three projects (A, B and C) are compiled/released at a different time.

Start with doing mvn dependency:tree on your project. Ask the verbose version of that. One typical cause is dependency versions overrides with a lower version. For example your project A depends on C 1.2 and B 3.0 but B 3.0 depends on C 1.4. What if B was compiled using a method of C that only exists since C 1.3? When B is run in project A with C 1.2 instead of C 1.4, it doesn't find that method and NoSuchMethodError is thrown.

Note: there is an enforcer rule to enforce not downgrading transitive dependencies. It's very useful to avoid such surprises at runtime.

Answered By - Geoffrey De Smet
Answer Checked By - Terry (JavaFixing Volunteer)