[ZEPPELIN-2241] JDBC interpreter throws npe on connecting to any db that has a schema with "null" name

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.7.1, 0.8.0
• Component/s: Interpreters
• Assignee: Randy Gelhausen
• Reporter: Randy Gelhausen
• Created: 10/Mar/17 04:58
• Updated: 15/Mar/17 15:23
• Resolved: 15/Mar/17 15:23

Description

For example, Apache Phoenix has a default schema without a name. Any JDBC command will throw a stacktrace on attempting to setup SQLCompleter's treemap.

I added logger statements to demonstrate the problem below:

INFO [2017-03-09 23:38:57,894] (

{pool-2-thread-2} SqlCompleter.java[initFromConnection]:363) - Completer initialized with 0 schemas, 0 tables and 281 keywords
INFO [2017-03-09 23:38:57,896] ({pool-2-thread-2}

JDBCInterpreter.java[interpret]:694) - Run SQL command 'select * from system.catalog'
INFO [2017-03-09 23:38:57,896] (

{pool-2-thread-2} JDBCInterpreter.java[interpret]:703) - PropertyKey: default, SQL command: 'select * from system.catalog'
INFO [2017-03-09 23:38:58,445] ({pool-2-thread-2}

SqlCompleter.java[getSqlKeywordsCompletions]:219) - JDBC DriverName:/phoenix-remote-jdbc-driver-sql.keywords
INFO [2017-03-09 23:38:58,526] (

{pool-2-thread-2} SqlCompleter.java[getSchemaNames]:114) - FOUND SCHEMA: null
INFO [2017-03-09 23:38:58,526] ({pool-2-thread-2}

SqlCompleter.java[getSchemaNames]:114) - FOUND SCHEMA: SYSTEM
INFO [2017-03-09 23:38:58,668] (

{pool-2-thread-2} SqlCompleter.java[initSchemas]:280) - Connection has 2 schemas
INFO [2017-03-09 23:38:58,668] ({pool-2-thread-2}

SqlCompleter.java[initSchemas]:281) - [null, SYSTEM]
ERROR [2017-03-09 23:38:58,669] (

{pool-2-thread-2}

JDBCInterpreter.java[executeSql]:642) - Cannot run select * from system.catalog
java.lang.NullPointerException
at java.util.TreeMap.compare(TreeMap.java:1290)
at java.util.TreeMap.put(TreeMap.java:538)
at java.util.TreeSet.add(TreeSet.java:255)
at java.util.AbstractCollection.addAll(AbstractCollection.java:344)
at java.util.TreeSet.addAll(TreeSet.java:312)
at java.util.TreeSet.<init>(TreeSet.java:160)
at org.apache.zeppelin.jdbc.SqlCompleter.initSchemas(SqlCompleter.java:283)
at org.apache.zeppelin.jdbc.SqlCompleter.init(SqlCompleter.java:322)
at org.apache.zeppelin.jdbc.SqlCompleter.initFromConnection(SqlCompleter.java:362)
at org.apache.zeppelin.jdbc.JDBCInterpreter.createSqlCompleter(JDBCInterpreter.java:209)
at org.apache.zeppelin.jdbc.JDBCInterpreter.getConnection(JDBCInterpreter.java:424)
at org.apache.zeppelin.jdbc.JDBCInterpreter.executeSql(JDBCInterpreter.java:576)
at org.apache.zeppelin.jdbc.JDBCInterpreter.interpret(JDBCInterpreter.java:704)
at org.apache.zeppelin.interpreter.LazyOpenInterpreter.interpret(LazyOpenInterpreter.java:94)
at org.apache.zeppelin.interpreter.remote.RemoteInterpreterServer$InterpretJob.jobRun(RemoteInterpreterServer.java:495)
at org.apache.zeppelin.scheduler.Job.run(Job.java:181)
at org.apache.zeppelin.scheduler.ParallelScheduler$JobRunner.run(ParallelScheduler.java:162)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)

Issue Links

• links to: GitHub Pull Request #2117