java.util.logging: how to suppress date line
Solution 1
The problem is caused by a handler in the parent log. The solution is to remove all handlers from the parent log, and then add own custom handler. This code removes handlers from the parent log:
for(Handler iHandler:log.getParent().getHandlers()) { log.getParent().removeHandler(iHandler); }
Solution 2
From Java SE 7 there is a new system property: java.util.logging.SimpleFormatter.format.
The same property is also configurable on the java.util.logging properties file (logging.properties). If you are an Eclipse user, and you are annoyed by the double line message in the console output, you could change the jre logging.properties file (JDK_HOME/jre/lib/logging.properties) in this way:
java.util.logging.SimpleFormatter.format=%4$s: %5$s [%1$tc]%n
Some example format is available here: http://docs.oracle.com/javase/7/docs/api/index.html?java/util/logging/SimpleFormatter.html.
Solution 3
Write a custom formatter extending java.util.logging.Formatter
class and implement the String format(LogRecord)
method according to your needs. For example, the following formatter shows only the log message (and the throwable stacktrace if an exception is being logged):
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.logging.Formatter;
import java.util.logging.LogRecord;
class CustomRecordFormatter extends Formatter {
@Override
public String format(final LogRecord r) {
StringBuilder sb = new StringBuilder();
sb.append(formatMessage(r)).append(System.getProperty("line.separator"));
if (null != r.getThrown()) {
sb.append("Throwable occurred: "); //$NON-NLS-1$
Throwable t = r.getThrown();
PrintWriter pw = null;
try {
StringWriter sw = new StringWriter();
pw = new PrintWriter(sw);
t.printStackTrace(pw);
sb.append(sw.toString());
} finally {
if (pw != null) {
try {
pw.close();
} catch (Exception e) {
// ignore
}
}
}
}
return sb.toString();
}
}
This is how you use it:
import java.util.logging.ConsoleHandler;
import java.util.logging.Logger;
class A {
private static final Logger LOGGER = Logger.getLogger(A.class.getName());
static {
CustomRecordFormatter formatter = new CustomRecordFormatter();
ConsoleHandler consoleHandler = new ConsoleHandler();
consoleHandler.setFormatter(formatter);
LOGGER.addHandler(consoleHandler);
}
public void doSomething() {
LOGGER.info("something happened");
}
}
andrewz
Updated on June 18, 2020Comments
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andrewz almost 4 years
I'm trying to suppress output of the date line durinng logging when using the default logger in java.util.logging. For example, here is a typical output:
Jun 1, 2010 10:18:12 AM gamma.utility.application info
INFO: ping: db-time=2010-06-01 10:18:12.0, local-time=20100601t101812, duration=180000
Jun 1, 2010 10:21:12 AM gamma.utility.application info
INFO: ping: db-time=2010-06-01 10:21:12.0, local-time=20100601t102112, duration=180000I would like to get rid of the
Jun 1, 2010...
lines, they just clutter my log output. How can I do this? -
andrewz almost 14 yearsI'll give this a try, but when I tried something similar last time it didn't work.
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Victor Parmar about 12 yearsNeed to follow andrew's answer below in addition to this :)
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PC. almost 11 yearsinstead
log.setUseParentHandlers(false);
can also be used -
bviktor about 9 yearsYou just saved our day, thanks mate. For the record, if you're using Tomcat, you can also change this under /etc/tomcat/logging.properties, you don't need to change the global Java settings.
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Tomáš Zato almost 7 yearsFormatter is final.
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Jesus H about 6 yearsIf you want to do this programmatically, see answer here: stackoverflow.com/questions/194765/…