Find a way to make exceptions more readable

[jakobbraun]

Considder the followijg example:

22002] VM error: java.lang.Exception: Unexpected error in adapter: Exception for table AUFTRAGSDATEN Stacktrace: java.lang.RuntimeException: Exception for table AUFTRAGSDATEN at com.exasol.adapter.jdbc.JdbcMetadataReader.findTables(JdbcMetadataReader.java:279)
 at com.exasol.adapter.jdbc.JdbcMetadataReader.readRemoteMetadata(JdbcMetadataReader.java:58) at com.exasol.adapter.jdbc.JdbcAdapter.readMetadata(JdbcAdapter.java:110) at com.exasol.adapter.jdbc.JdbcAdapter.readMetadata(JdbcAdapter.java:102) at com.exasol.adapter.jdbc.JdbcAdapter.handleRefresh(JdbcAdapter.java:128)
 at com.exasol.adapter.jdbc.JdbcAdapter.adapterCall(JdbcAdapter.java:68) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at
 java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:566) at com.exasol.ExaWrapper.runSingleCall(ExaWrapper.java:95) Caused by: com.exasol.adapter.metadata.MetadataException:
 A table without columns was encountered: AUFTRAGSDATEN. This is not supported. Please check if this table has columns. If the table does have columns, the dialect probably does not properly handle the data types of the columns. at com.exasol.adapter.metadata.TableMetadata.(TableMetadata.java:23)
 at com.exasol.adapter.jdbc.JdbcMetadataReader.findTables(JdbcMetadataReader.java:277) ... 10 more For following request: { "schemaMetadataInfo" : { "name" : "AUFTRAGSDATEN", "properties" : { "CONNECTION_NAME" : "AUFTRAGSDATEN",
 "EXA_CONNECTION_STRING" : "AUFTRAGSDATEN", "IMPORT_FROM_EXA" : "true", "SCHEMA_NAME" : "AUFTRAGSDATEN", "SQL_DIALECT" : "EXASOL" } }, "type" : "refresh" } Response: Stack trace: com.exasol.adapter.jdbc.JdbcAdapter.adapterCall(JdbcAdapter.java:90)
 java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
 java.base/java.lang.reflect.Method.invoke(Method.java:566) com.exasol.ExaWrapper.runSingleCall(ExaWrapper.java:95) (Session: 1690147644996459941)

The important part of the message is A table without columns was encountered: AUFTRAGSDATEN. This is not supported. Please check if this table has columns. If the table does have columns, the dialect probably does not properly handle the data types of the columns.. It is, however right in the middle of the message, to customers, usually won't find it.

Maybe we could figure out some solution, to improve this.

One Idea is to pick the last error message with an Exasol error code and prepend it as first message.