Why is the exception stack trace not logged in?

Question

I tried a simple example from the SLF4J FAQ :

package com.aed.tests.logging; import org.slf4j.LoggerFactory; public class TestLogging { public TestLogging() { // TODO Auto-generated constructor stub } /** * @param args */ public static void main(String[] args) { String s = "Hello world"; try { Integer i = Integer.valueOf(s); } catch(NumberFormatException e) { LoggerFactory.getLogger("simplelogger").error("Failed to format {}", s, e); LoggerFactory.getLogger("simplelogger").error("Without parametrized string", e); } } } 

Here is the result:

 15:33:51,248000000 [SEVERE]simplelogger: Failed to format Hello world 15:33:51,275000000 [SEVERE]simplelogger: Without parametrized string 

I use java.util.logging as a log implementation, with the following logging.properties

 # Properties file which configures the operation of the JDK # logging facility. # The system will look for this config file, first using # a System property specified at startup: # # >java -Djava.util.logging.config.file=myLoggingConfigFilePath # # If this property is not specified, then the config file is # retrieved from its default location at: # # JDK_HOME/jre/lib/logging.properties # Global logging properties. # ------------------------------------------ # The set of handlers to be loaded upon startup. # Comma-separated list of class names. # (? LogManager docs say no comma here, but JDK example has comma.) handlers=java.util.logging.ConsoleHandler # Default global logging level. # Loggers and Handlers may override this level .level=ALL # Loggers # ------------------------------------------ # Loggers are usually attached to packages. # Here, the level for each package is specified. # The global level is used by default, so levels # specified here simply act as an override. # myapp.ui.level=ALL # myapp.business.level=CONFIG # myapp.data.level=SEVERE # Handlers # ----------------------------------------- # --- ConsoleHandler --- # Override of global logging level java.util.logging.ConsoleHandler.level=ALL java.util.logging.ConsoleHandler.formatter=java.util.logging.SimpleFormatter # HH:MM:ss,nanosec java.util.logging.SimpleFormatter.format=%1$tT,%1$tN [%4$s]%3$s: %5$s %n 

I was expecting to see stacktrace exceptions. Am I missing something in the configuration? Should I somehow enable straw restriction tracing with the SLF4J or jdk protocol?

EDIT After "Marked as duplicate." My question was not “how to print the stack trace”, but how does it turn out, using the very example SLF4J, which itself performs the task to print the stack trace, I still did not print the stack trace. As I said, I had a stack trace using log4j as an implementation, but not java.util.logging. So it really was the wrong java.util.logging configuration, and I gave the answer when I found out.

Answer 1

It really is a matter of properly formatting the log entries.

As the manual says, throwable is the 6th parameter of the method format. So I added %6$s to my format in logging.properties:

 java.util.logging.SimpleFormatter.format=%1$tT,%1$tN [%4$s]%3$s: %5$s %6$s %n 

And here is the result showing the stack trace:

 17:29:33,314000000 [SEVERE]simplelogger: Failed to format Hello world java.lang.NumberFormatException: For input string: "Hello world" at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65) at java.lang.Integer.parseInt(Integer.java:492) at java.lang.Integer.valueOf(Integer.java:582) at com.aed.tests.logging.TestLogging.main(TestLogging.java:15) 17:29:33,344000000 [SEVERE]simplelogger: Without parametrized string java.lang.NumberFormatException: For input string: "Hello world" at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65) at java.lang.Integer.parseInt(Integer.java:492) at java.lang.Integer.valueOf(Integer.java:582) at com.aed.tests.logging.TestLogging.main(TestLogging.java:15) 

Answer 2

java.lang.Exception.toString() does not return stack trace information. From the documentation :

Returns a brief description of this throw.

see How to convert stack trace to string? and register String , which you will return.