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How to disable Log4j for OpenNLP via log4j.properties

I use Log4j and I import OpenNLP via Maven. Now I want to disable the log output (in red) which is printed in syso from opennlp.
I tried to add to my log4j.properties:
# Root logger option
log4j.rootLogger=INFO, stdout
# Direct log messages to stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.org.opennlp=OFF
The last line should hide opennlp messages such as:
Average: 1000,0 sent/s
Total: 1 sent
Runtime: 0.001s
but does not work. Please tell me why?

OpenNLP is not using Log4j, or any other logging framework. The command line interface prints directly to stdout. The command line tools are only useful for training/evaluating and testing.
For production use you should integrate OpenNLP via its Java API, or via some other framework like Apache UIMA.

I want to log data in a file which is displayed on java console when I run .jar file

I have a .jar file I am executing that with java -jar file_name.jar.
Then the program outputs to the IDE console, a prompt asking the user for credentials. After authenticating, the program prints database data to the console.
How can I redirect the console data output to a filestream?
I tried adding logger while executing the command java -jar file_name.jar. But no success.
I am not a java person, so I don't have any idea how to do that.
Any suggestion or help will be great.
EDIT
Screenshot addded for the GUI screen

if it's from java console:
java -jar class.jar <someFile.file> 1>> log.txt

since you said that you have access to the jar's sources then the simplest way you can just add the following at startup class:
import java.util.logging.Logger;
Handler handler = new FileHandler("test.log", LOG_SIZE, LOG_ROTATION_COUNT);
Logger logger = Logger.getLogger("MyLogger").addHandler(handler);
and with logger you log what you log in the console.
You can specify your own values for LOG_SIZE and LOG_ROTATION_COUNT
You may, if you want, adjust the logging level to suit.

Jar file ran by cron doesn't write his own log

I have a simple java program (Java version 1.7), which is an email sender, and I want to log some events during its running. So I decided to use org.apache.log4j.Logger for this. I created the log4j.properties file which contains the following:
log4j.rootLogger=INFO, file
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=Autoemail.log
log4j.appender.file.MaxFileSize=2MB
log4j.appender.file.MaxBackupIndex=10
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{dd/MM/yyyy HH:mm:ss,SSS} %5p %c{1}:%L - %m%n
log4j.appender.file.encoding=UTF-8
This is how I load the configuration:
PropertyConfigurator.configure(cl.getResource("resources/log4j.properties"));
logger = Logger.getLogger("");
logger.info("Auto email sending started...");
where cl is the classloader. When I run this from Eclipse on my localhost, everything works as desired, the log file has been created if didn't exist, and on next run it is appended.
Then I wanted to run this email sender program automatically every day at 7 am. I created the scheduled cron job, which executes the following:
java -jar /var/projects/Autoemail/Autoemail.jar 2>> /var/projects/Autoemail/Autoemail.err
On first run it worked fine, the log file had been created and info or error had been inserted, but since then the program doesn't write any event into it. The jar file runs, because I can see the sent emails. When I started searching for the reason, and ran the command, it showed me a Permission denied error. I checked the rights of the log file, and it was: rw-rw-r--. So I modified, at last to rwxrwxrwx, but still doesn't write the log, and I can't see any error message in the syslog file. The owner doesn't need sudo right, I think. BTW the server is Ubuntu 13/04.
Does anyone have any idea of what can be wrong, what is still needed, or what do I have to do?

configuring log4j to display errors

I've configured my log4j.properties so that it puts all the info and debug messages in a separate log file in tomcat. However, when the application fails, say bad sql command then the errors don't show up in that file but instead show up in the regular localhost log file.
How can I configure the properties such that the errors show up in that file as well?
log4j.rootCategory=INFO, logfile
log4j.appender.logfile=org.apache.log4j.RollingFileAppender
log4j.appender.logfile.layout=org.apache.log4j.PatternLayout
log4j.appender.logfile.layout.ConversionPattern=%d %p [%c] - <%m>%n
log4j.appender.logfile.File=${catalina.home}/logs/myapplog.log
log4j.category.org.springframework.web=INFO
log4j.category.com.package.app=DEBUG
log4j.category.org.springframework.samples.mvc31=INFO
log4j.logger.org.springframework.jdbc.core=DEBUG
The type of errors I want to see in my log file are like these:
com.microsoft.sqlserver.jdbc.SQLServerException: Invalid column name...

If you are catching the exceptions/errors(Throwable) and putting log.error statements in your catch blocks then only you will be able to see the exception messages in your log file. For all the exceptions that are not caught in your code will be basically pushed to the console logger of tomcat and hence you are seeing the exception traces in tomcat out log file.
So try to catch all the possible exceptions in your code and log them properly so that they appear in your log files.

SLF4J Logger does clear console output sometimes (unwantedly)

I am using SLF4J + Logback to output messages to the eclipse IDE console.
Logger LOG = LoggerFactory.getLogger(MyClass.class);
LOG.debug("test");
But sometimes the whole console output gets cleared and i cannot see older messages. Is that enough information so that you can help me out?

It sounds like you might be hitting the default console output limit in Eclipse. You can edit it under Window > Preferences > Run/Debug > Console. Either increase the console buffer size (default is 80000 characters) or uncheck the "limit console output" box.