Yugabyte-db: yb-client jar compiled against jdk 11 does not work with jdk 8

[iSignal]

Repro steps:

1. Create a yb cluster locally at 127.0.0.1 by running yb-ctl or yugabyted
2. Ensure java -version shows > Java 8 (Java 9 at least) and run ./yb_build.sh --java-only
3. Install Java 8 in a different dir. Run <path to java8> -jar java/yb-cli/target/yb-cli-0.8.0-SNAPSHOT.jar. At the prompt, type the commands connect --masters 127.0.0.1:7100 and list masters
4. See the error Failed to fetch masters info for database at 127.0.0.1:7100, error: com.stumbleupon.async.TimeoutException: Timed out after 10000ms when joining Deferred@503928724(state=RUNNING, result=tablet_locations { tablet_id: "YB Master" replicas { ts_info { permanent_uuid: "e4443d784f6847c08a792e6f2535f667" private_rpc_addresses { host: "127.0.0.1" port: 7100 } } role: LEADER } stale: false partition { partition_key_start: "" partition_key_end: "" } } , callback=release master lookup permit -> retry RPC -> wakeup thread Spring Shell, errback=release master lookup permit -> retry RPC after error -> wakeup thread Spring Shell)

The same error also repros through YW create universe.

---

When running with DEBUG logging the full details of the error are seen (ips are different):

2020-12-20 19:50:12 DEBUG TabletClient:606 - [Peer YB Master - 172.151.29.141:7100] [id: 0xd2aa4ea4, /10.150.0.148:43978 => /172.151.29.141:7100] EXCEPTION: java.lang.NoSuchMethodError: java.nio.CharBuffer.flip()Ljava/nio/CharBuffer;
2020-12-20 19:50:12 DEBUG TabletClient:700 - [Peer YB Master - 172.151.29.141:7100] Unexpected exception java.nio.CharBuffer.flip()Ljava/nio/CharBuffer; from downstream on [id: 0xd2aa4ea4, /10.150.0.148:43978 => /172.151.29.141:7100]
java.lang.NoSuchMethodError: java.nio.CharBuffer.flip()Ljava/nio/CharBuffer;
        at org.yb.util.Slices.decodeString(Slices.java:174)
        at org.yb.util.Slice.toString(Slice.java:705)
        at org.yb.util.Slice.toString(Slice.java:692)
        at org.yb.client.AsyncYBClient.discoverTablets(AsyncYBClient.java:1679)
        at org.yb.client.AsyncYBClient$MasterLookupCB.call(AsyncYBClient.java:1603)
        at org.yb.client.AsyncYBClient$MasterLookupCB.call(AsyncYBClient.java:1595)
        at com.stumbleupon.async.Deferred.doCall(Deferred.java:1280)
        at com.stumbleupon.async.Deferred.runCallbacks(Deferred.java:1259)
        at com.stumbleupon.async.Deferred.callback(Deferred.java:1002)
        at org.yb.client.GetMasterRegistrationReceived$GetMasterRegistrationCB.call(GetMasterRegistrationReceived.java:193)
        at org.yb.client.GetMasterRegistrationReceived$GetMasterRegistrationCB.call(GetMasterRegistrationReceived.java:165)
        at com.stumbleupon.async.Deferred.doCall(Deferred.java:1280)
        at com.stumbleupon.async.Deferred.runCallbacks(Deferred.java:1259)
        at com.stumbleupon.async.Deferred.callback(Deferred.java:1002)
        at org.yb.client.YRpc.handleCallback(YRpc.java:180)
        at org.yb.client.YRpc.callback(YRpc.java:193)
        at org.yb.client.TabletClient.decode(TabletClient.java:440)
        at org.yb.client.TabletClient.decode(TabletClient.java:98)
        at org.jboss.netty.handler.codec.replay.ReplayingDecoder.callDecode(ReplayingDecoder.java:500)
        at org.jboss.netty.handler.codec.replay.ReplayingDecoder.messageReceived(ReplayingDecoder.java:435)
        at org.yb.client.TabletClient.handleUpstream(TabletClient.java:608)
        at org.jboss.netty.handler.timeout.ReadTimeoutHandler.messageReceived(ReadTimeoutHandler.java:184)
        at org.yb.client.AsyncYBClient$TabletClientPipeline.sendUpstream(AsyncYBClient.java:2088)
        at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:268)
        at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:255)
        at org.jboss.netty.channel.socket.nio.NioWorker.read(NioWorker.java:88)
        at org.jboss.netty.channel.socket.nio.AbstractNioWorker.process(AbstractNioWorker.java:108)
        at org.jboss.netty.channel.socket.nio.AbstractNioSelector.run(AbstractNioSelector.java:318)
        at org.jboss.netty.channel.socket.nio.AbstractNioWorker.run(AbstractNioWorker.java:89)
        at org.jboss.netty.channel.socket.nio.NioWorker.run(NioWorker.java:178)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at java.lang.Thread.run(Thread.java:748)

The reason for this error is that the flip method of CharBuffer has a different signature in Java 8 and Java 11 (returns ByteBuffer vs Buffer). This causes a "runtime link" error (a more accurate description is at https://github.com/apache/felix/pull/114).

@Arnav15

[gunnarmorling]

To prevent this, build with --release=8 instead of --source and --target. At Debezium, we also happened to run into this, and I blogged about it just today :)

[iSignal]

@gunnarmorling : Your blog post is the clearest description of the underlying signature mismatch I've seen on this topic so far, thanks for writing it and pointing us to it.