How do I view java log files in Eclipse

Question

I am running some JUnit tests in Eclipse, and my code is generating an XML log file using the java logging APIs. (java.util.logging). Is there an easy way to view this XML log output in Eclipse, other than reading the raw XML? Specifically I want to be able to easily see what threads different log messages have come from.

Answer 1

I've been using the SLF4J logging API coupled with the Logback logging implementation. SLF4J can be configured to map log messages in the java.util.logging, log4j, jakarta commons logging, and SLF4j APIs into a common intermediate form. On the other side, the messages can be generated via java.util.logging, log4j, or Logback. It's a flexible approach that works well, especially when you have components that use different logging APIs.

One nice thing about Logback is that you can configure it to send a copy of the log messages to a an Eclipse plug-in . The plug-in and lets you view and filter the log file in a variety of ways. Messages contain the thread that generated them, so it sounds like something you should check out.

Answer 2

If you want to use log viewer which is not based on eclipse, I recommend you OtrosLogViewer . I can import java.util.logging XML format and SimpleFormat.

Disclaimer : I am the author of OtrosLogViewer

Answer 3

I think you were looking for the same thing I was looking for. I found UtilLogger4E, but I started my own project (EDevTools LogViewer), because it has some missing features and is not opensource.

It has the abilities to read Java Util Logging XML logs from a file or a configurable socket, display them colored by level in a table and it can show more than one log at a time (through multiple view instances).

Java Util Logging has a built-in feature to send logs to a socket (SocketHandler), it must only be set by the configuration file.

You can take a look at LogViewer at: http://sourceforge.net/projects/edevtools/

Answer 4

I was always hoping to find something like Apache Chainsaw for the java.util.logging/Eclipse combination, ie a log viewer in Eclipse that listens to a port and a java.util.logging.Handler implementation writing directly to that. But I haven't found such thing yet and didn't get around writing one either. So far I just use a suitable plain-text format to log to the console. Not elegant and no handy filtering options, but it does the job. Writing your own custom formatter is not hard at all.

There is some support for analyzing log files in Eclipse's Test and Performance Tools Platform Project (the name being even worse than the acronym). I never tried that, but it might be useful for you.

Answer 5

Just on the side, an excellent tool for viewing log files in real-time is baretail (essentially a tail -f on Windows), but can be set up to highlight certain patterns in colour which can really help. You can find a free version here .

Answer 6

Depending on exactly what you're trying to do you might just need a good logging setup for your logging sub sys?

A framework I've been using recently uses slf4j to log, by providing the following log4j config I get to see which threads output what:

log4j.rootLogger = trace, default
log4j.appender.default = org.apache.log4j.ConsoleAppender
log4j.appender.default.layout = org.apache.log4j.PatternLayout
log4j.appender.default.layout.ConversionPattern = %-4r [%t] %-5p %c %x - %m%n

In my case I get output similar to the following in the Console tab in eclipse when I run my junit tests.

0    [pool-1-thread-1] INFO  com.example.BaseTest  - Server listening on port 9090
35   [NioProcessor-6] INFO  org.apache.mina.filter.logging.LoggingFilter  - CREATED
35   [NioProcessor-1] INFO  org.apache.mina.filter.logging.LoggingFilter  - CREATED

Answer 7

I don't see how Eclipse can know about your threads. If it's XML, you need to write a parser that can find your thread messages using XPath and print them out. But that's up to you - Eclipse can't read your mind.

You'll have to find an XSL-T stylesheet that can take the XML stream produced by log4j and pull out the threads that you want.