NoSuchMethodError: org.codehaus.jackson.type.JavaType

Question

My application is throwing the error below, although I have in my app the jackson-core-asl-1.4.2 and jackson-mapper-asl-1.4.2

Cause         


        

Answer 1

This looks almost certainly to be due to incompatible versions of 'core' and 'mapper' jars. You probably have incompatible versions in use via classpath.

Answer 2

The problem you are having is due to an update in Google App Engine SDK (I think 1.6.1?).

I had the same problem, so I ran TattleTale to see if there are some dependency issues. Lo and behold, there is a conflict on the org.codehaus.* with the following 2 libraries:

• google_sql.jar
• jackson-core-asl-1.6.3.jar

While your jackson libraries are slightly different than mine, the issue remains the same. There are 2 fixes to this issue:

• Remove google_sql.jar from war/webinf/lib directory. This will cause the SDK to fail validation checks, but if you ignore the red x's your code should run fine.
• Update your GAE SDK to 1.6.2 or above. I think they fixed the issue in later SDK's but the updates also introduced some compiler warnings so look before you leap.