nod
cmaj135
2010-08-07
发件人： Doug Bateman
发送时间： 2010-08-07 10:11:35
收件人： Commons Developers List
抄送：
主题： LogFactory.getLog()
Dear Commons Developers,
Here's a suggestion for the commons-logging package...
Presently, in Apache Commons, the most common way to get a logger is to do
something like:
public class MyClass {
private static Log log = LogFactory.getLog(MyClass.class);
}
Notice how MyClass.class (or alternatively a string name) is passed as a
parameter. The annoying aspect of this is that sometimes the class name
doesn't get updated when doing copy/paste operations. A desirable alternative
might be:
public class MyClass {
private static Log log = LogFactory.getLog(); //class name inferred from
call stack
}
With such an approach there are two possible concerns I can foresee:
Call stack inspection isn't terribly fast. However since Loggers are generally
initialized only once, when the class is first loaded, performance isn't likely
to be a major problem.
Commons-logging is Java 1.1 compatible. Thus care must be taken to ensure
compatibility isn't broken.
Commons-logging doesn't depend on commons-lang, and thus the utilities in
commons-lang cannot be used.
In Java 1.4, the call stack is easily obtained using Thread.getCallStack().
Prior to Java 1.4, the only way to obtain the call stack is to inspect the
stack trace of an exception.
I've attached to this email a proof of concept implementation. It tests
successfully in Java 1.0+ and Java 1.4+. In order to ensure the implementation
doesn't break for Java 1.0, I used reflection to invoke the Java 1.4 APIs when
they are available.
Cheers,
Doug
