SQLException when accessing H2 metamodel through JOOQ-meta - jdbc

Question

I am trying to obtain a list of all tables in my H2 in-memory DB using JOOQ's DSLContext.meta():
DSL_CONTEXT_PROVIDER.db().meta().getTables();
results in:
java.lang.RuntimeException: org.jooq.exception.DataAccessException: Error while accessing DatabaseMetaData
at MyTest.deleteEntities(MyTest.java:222)
at MyTest.cleanupDatabase(MyTest.java:201)
at MyTest.afterTestCase(MyTest.java:117)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
[... omitted for brevity ...]
Caused by: org.jooq.exception.DataAccessException: Error while accessing DatabaseMetaData
at org.jooq.impl.MetaImpl.getCatalogs(MetaImpl.java:160)
at org.jooq.impl.MetaImpl.getSchemas(MetaImpl.java:168)
at org.jooq.impl.MetaImpl.getTables(MetaImpl.java:179)
at MyTest.deleteEntities(MyTest.java:210)
... 29 more
Caused by: org.h2.jdbc.JdbcSQLException: The object is already closed [90007-174]
at org.h2.message.DbException.getJdbcSQLException(DbException.java:332)
at org.h2.message.DbException.get(DbException.java:172)
at org.h2.message.DbException.get(DbException.java:149)
at org.h2.message.DbException.get(DbException.java:138)
at org.h2.jdbc.JdbcConnection.checkClosed(JdbcConnection.java:1410)
at org.h2.jdbc.JdbcConnection.checkClosed(JdbcConnection.java:1388)
at org.h2.jdbc.JdbcDatabaseMetaData.checkClosed(JdbcDatabaseMetaData.java:2963)
at org.h2.jdbc.JdbcDatabaseMetaData.getCatalogs(JdbcDatabaseMetaData.java:756)
at org.jooq.impl.MetaImpl.getCatalogs(MetaImpl.java:143)
... 32 more
DSL_CONTEXT_PROVIDER.db() looks like this:
JdbcDataSource h2ds = new JdbcDataSource();
h2ds.setURL("jdbc:h2:mem:testDB;create=true");
h2ds.setUser("");
h2ds.setPassword("");
return DSL.using(new DefaultConfiguration().set(new DataSourceConnectionProvider(h2ds)));
Ordinary queries work fine with the above configuration, but not the meta().getTables(). If I replace DataSourceConnectionProvider with an anonymous implementation that doesn't close the connection, no exception is thrown anymore.
It seems H2 does not approve of calling methods like getCatalogs() on the object returned by connection.getMetaData() after the underlying connection has been closed. Is this this a bug in jooq-meta (I use 3.7.0) or is my configuration flawed?

Answer 1

jOOQ 3.7.0 / 3.7.1 and earlier are caching the DatabaseMetaData in org.jooq.Meta. This is a bug (4762) and will be fixed soon.
The reason why you're running into this issue is because you're using the DataSourceConnectionProvider, which isn't really intended to work with standalone connections, or "simple" DataSources. It closes the connection after every query (which normally translates to returning it to the pool). After closing the connection, the cached DatabaseMetaData reference is stale.
You've already documented the workaround: Don't use a "simple" DataSource with jOOQ's DSLContext.meta() API.