Why does Java HSQL throw an AbstractMethodError exception?
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I'm getting an AbstractMethodError exception from a GIS library using HSQL. I image this is caused by a configuration issue on my machine, but I'm not sure if its related to the JRE, or some other system lib. Here is the error:

    Exception in thread "main" java.lang.AbstractMethodError: org.hsqldb.jdbc.jdbcResultSet.isClosed()Z

