[CURATOR-509] Incompatible with Java 11

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 4.1.0
• Fix Version/s: 4.2.0
• Component/s: Apache
• Environment: java 11.0.2 on windows and linux
• Assignee: Jordan Zimmerman
• Reporter: Brian Vella
• Created: 01/Mar/19 07:42
• Updated: 01/Mar/19 16:53
• Resolved: 01/Mar/19 16:44

Description

In java 11, this exception is thrown:

java.lang.IncompatibleClassChangeError: Inconsistent constant pool data in classfile for class org/apache/curator/framework/CuratorFramework. Method lambda$postSafeNotify$0(Ljava/lang/Object;)V at index 99 is CONSTANT_MethodRef and should be CONSTANT_InterfaceMethodRef

at org.apache.curator.framework.CuratorFramework.postSafeNotify(CuratorFramework.java:344)

at org.apache.curator.framework.recipes.locks.InterProcessSemaphoreV2$1.process(InterProcessSemaphoreV2.java:90)

at org.apache.curator.framework.imps.NamespaceWatcher.process(NamespaceWatcher.java:77)

at org.apache.zookeeper.ClientCnxn$EventThread.processEvent(ClientCnxn.java:533)

at org.apache.zookeeper.ClientCnxn$EventThread.run(ClientCnxn.java:508)

As I understood it, this is because there is a lambda in a default interface method and earlier versions of java 8 incorrectly compiled the method reference as a Method instead of an Interface method. Compiling with the latest java 8 compiler (8.0.172) seems to correctly compile the classin a way that works in java 8 and 11 (did not verify 9 and 10 but I suspect they behave like 11)