Functionality of Translator Errors, Messages, and Exit Codes

This section provides an overview of SQLJ translator messages and exit codes.

Translator Error, Warning, and Information Messages

There are three major levels of SQLJ messages you may encounter during the translation phase: error, warning, and information. Warning messages can be further broken down into two levels: non-suppressable and suppressable. Therefore, there are four message categories (in order of seriousness):

1. errors

2. non-suppressable warnings

3. suppressable warnings

4. information

You can control suppressable warnings and information by using the SQLJ -warn option, as described below.

Error messages, prefixed by Error:, indicate that one of the following has been encountered:

• a condition that would prevent compilation (for example, the source file contains a public class whose name does not match the base file name)

• a condition that would almost certainly result in a runtime error if the code were executed (for example, the code attempts to fetch a VARCHAR into a java.util.Vector, using an Oracle JDBC driver)

If errors are encountered during SQLJ translation, then no output is produced (.java file or profiles) and compilation and customization are not executed.

Non-suppressable warning messages, prefixed by Warning:, indicate that one of the following has been encountered:

• a condition that would likely, but not necessarily, result in a runtime error if the code were executed (for example, a SELECT statement whose output is not assigned to anything)

• a condition that compromises SQLJ's ability to verify runtime aspects of your source code (for example, not being able to connect to the database you specify for online checking)

• a condition that presumably resulted from a coding error or oversight

SQLJ translation will complete if a non-suppressable warning is encountered but you should analyze the problem and determine if it should be fixed before running the application. If online checking is specified but cannot be completed, offline checking is performed instead.

Note: For logistical reasons, the parser that the SQLJ translator employs to analyze SQL operations is not the same top-level parser that will be used at runtime. Therefore, errors may occasionally be detected during translation that will not actually cause problems when your application runs. Accordingly, such errors are reported as non-suppressable warnings rather than fatal errors.

Suppressable warning messages, also prefixed by Warning:, indicate that there is a problem with a particular aspect of your application, such as portability. For example, retrieving data from a nullable column into a primitive int variable. These messages can be suppressed by using the various -warn option flags:

• precision/noprecision--The noprecision setting suppresses warnings regarding possible loss of data precision during conversion.

• nulls/nonulls--The nonulls setting suppresses warnings about possible runtime errors that are due to nullable columns or types.

• portable/noportable--The noportable setting suppresses warnings regarding SQLJ code that uses Oracle-specific features or may otherwise be non-standard and, therefore, not portable to other environments.

• strict/nostrict--The nostrict setting suppresses warnings issued if there are fewer columns in a named iterator than in the selected data that is to populate the iterator.

See "Translator Warnings (-warn)" for more information about the -warn option and how to set the flags.

If you receive warnings during your SQLJ translation, then you can try running the translator again with -warn=none to see if any of the warnings are of the more serious (non-suppressable) variety.

Informational or status messages prefixed by Info: do not indicate an error condition. They merely provide additional information about what occurred during the translation phase. These messages can be suppressed by using the -warn option verbose flag, as follows:

• verbose/noverbose--The noverbose setting suppresses status messages that are merely informational and do not indicate error or warning conditions.

Table 9-1 summarizes the categories of error and status messages generated by the SQLJ translator.

Table 9-1 SQLJ Translator Error Message Categories

Message Category	Prefix	Indicates	Suppressed By
error	Error:	fatal error that will cause compilation failure or runtime failure (translation is aborted)	n/a
non-suppressable warning	Warning:	condition that prevents proper translation or might cause runtime failure (translation is completed)	n/a
suppressable warning	Warning:	problem regarding a particular aspect of your application (translation is completed)	-warn option flags: noprecision nonulls noportable nostrict
informational/status message	Info:	information regarding the translation process	-warn option flags: noverbose

Translator Status Messages

In addition to the translator's error, warning, and information messages, SQLJ can produce status messages throughout all phases of SQLJ operation--translation, compilation, and customization. Status messages are output as each file is processed and at each phase of SQLJ operation.

You can control status messages by using the SQLJ -status option. This option is also discussed in "Real-Time Status Messages (-status)".

Translator Exit Codes

The following exit codes are returned by the SQLJ translator to the operating system upon completion:

• 0 = no error in execution

• 1 = error in SQLJ execution

• 2 = error in Java compilation

• 3 = error in profile customization

• 4 = error in class instrumentation (the optional mapping of line numbers from your .sqlj source file to the resulting .class file)

• 5 = error in ser2class conversion (the optional conversion of profile files from .ser files to .class files)

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