Javac error messages are generated by consulting a so-called resource file that contains entries of the following kind:

compiler.err.annotation.missing.default.value=\
    annotation {0} is missing value for the attribute {1}

When translating an error message in a foreign language, it is usually crucial to know detailed info about the values assumed by the diagnostic arguments ({0} and {1} in the above example). However, not all the resource keys in compiler.properties are well-documented - this makes i10n hard.

It would be great if we could automatically generate info about the types of the arguments supplied by the compiler for each resource key - for example, we could automatically generate the following comment line:

# {0} = Java type, {1} = Java identifier