Programmatically creating different log files using log4j

I have an automated integration test harness and would like to streamline the logging (which is implemented usi开发者_JAVA技巧ng log4j)

I have a number of high-level tests, each with an id and require a separate log file per test. As the tests are created randomly the ids are not known until runtime.

Therefore I would like to ensure that logging within each high-level test is written out to the log file for that test.

I don't want to create custom log levels, neither do I want to have logging sent to all appenders.

Does anyone know a way of doing this?

You can easily invoke log4j's API programmatically, e.g.

FileAppender appender = new FileAppender();
// configure the appender here, with file location, etc
appender.activateOptions();

Logger logger = getRootLogger();
logger.addAppender(appender);

The logger can be the root logger as in this example, or any logger down the tree. Your unit test can add its custom appender during steup, and remove the appender (using removeAppender()) during teardown.