Issue 367

[liweinan]

No description provided.

[liweinan]

Generally speaking, this allows the user to define the prop like:

db-user = ${DB_USER:default_user}
db-pass = ${DB_PASS:default_pass}

And the environment variables DB_USER and DB_PASS will be passed in.

If the default values are not exist, the prop should be defined like this:

db-user = ${DB_USER:}
db-user = ${DB_PASSWD:}

The colon should not be omitted because it simplify the regexp processing pattern and ensure the efficiency.

@chengfang Do you agree with this solution?

[chengfang]

@liweinan we can limit the change to jberet-se classes like BatchSEEnvironment.java? Since this new feature will only be available for JBeret in Java SE. jberet-core classes like JdbcRepository should be able to remain intact.

mongodb job repository also uses db-user and db-password, so having these changes in BatchSEEnvironment.java will also cover mongo repository.

From a user's point of view, it is a bit surprise to be required to use : in the expression. This is not what users do the similar expression in other environment so if possible, I would keep it consistent with everywhere else by not requiring the :

[liweinan]

@chengfang Okay! I'll do the modification accordingly.

[liweinan]

@chengfang I have refactored the impl according to your suggestion, could you please help to review it again? Thanks!

[liweinan]

@chengfang Thanks for the suggestion! I have updated the PR accordingly. Could you please help to to review it again? If it's okay I'll squash the commits.

[liweinan]

@chengfang Thanks for the suggestions! Today is too late I'll finish updating this PR during the weekend :D

[liweinan]

@chengfang I have finished updating this PR according to your review comments, could you please help to review it again? Thanks!

[liweinan]

Thanks for checking @chengfang I'll do the cleanup and merge this.