How to fix "JARs that were scanned but TLDs were not found in them" in Tomcat 9.0.0M10

Question

I am new to Java EE and trying to work on a ServletContextListener, and working with a listener is connecting to the bla bla database. When I try to start the server (Tomcat 9), it is stuck:

"INFO: at least one JAR was scanned for a TLD but did not contain a TLD. Turn on debug logging for this logger for a complete list of JARs that were scanned but not a single TLD was found in them. Skipping unnecessary JARs during scanning can improve the startup time and compilation time of the JSP. "

So, I changed some properties in the "logging properties file" as follows:

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# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# limitations under the License.

handlers = 1catalina.org.apache.juli.AsyncFileHandler, 2localhost.org.apache.juli.AsyncFileHandler, 3manager.org.apache.juli.AsyncFileHandler, 4host-manager.org.apache.juli.AsyncFileHandler, java.util.logging.ConsoleHandler

.handlers = 1catalina.org.apache.juli.AsyncFileHandler, java.util.logging.ConsoleHandler

############################################################
# Handler specific properties.
# Describes specific configuration info for Handlers.
############################################################

1catalina.org.apache.juli.AsyncFileHandler.level = FINE
1catalina.org.apache.juli.AsyncFileHandler.directory = ${catalina.base}/logs
1catalina.org.apache.juli.AsyncFileHandler.prefix = catalina.

2localhost.org.apache.juli.AsyncFileHandler.level = FINE
2localhost.org.apache.juli.AsyncFileHandler.directory = ${catalina.base}/logs
2localhost.org.apache.juli.AsyncFileHandler.prefix = localhost.

3manager.org.apache.juli.AsyncFileHandler.level = FINE
3manager.org.apache.juli.AsyncFileHandler.directory = ${catalina.base}/logs
3manager.org.apache.juli.AsyncFileHandler.prefix = manager.

4host-manager.org.apache.juli.AsyncFileHandler.level = FINE
4host-manager.org.apache.juli.AsyncFileHandler.directory = ${catalina.base}/logs
4host-manager.org.apache.juli.AsyncFileHandler.prefix = host-manager.

java.util.logging.ConsoleHandler.level = FINE
java.util.logging.ConsoleHandler.formatter = org.apache.juli.OneLineFormatter


############################################################
# Facility specific properties.
# Provides extra control for each logger.
############################################################

org.apache.catalina.core.ContainerBase.[Catalina].[localhost].level = FINE
org.apache.catalina.core.ContainerBase.[Catalina].[localhost].handlers = 2localhost.org.apache.juli.AsyncFileHandler

org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/manager].level = FINE
org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/manager].handlers = 3manager.org.apache.juli.AsyncFileHandler

org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/host-manager].level = FINE
org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/host-manager].handlers = 4host-manager.org.apache.juli.AsyncFileHandler

# For example, set the org.apache.catalina.util.LifecycleBase logger to log
# each component that extends LifecycleBase changing state:
#org.apache.catalina.util.LifecycleBase.level = FINE

# To see debug messages in TldLocationsCache, uncomment the following line:
org.apache.jasper.compiler.TldLocationsCache.level = FINE
org.apache.jasper.servlet.TldScanner.level = FINE

# To see debug messages for HTTP/2 handling, uncomment the following line:
#org.apache.coyote.http2.level = FINE

# To see debug messages for WebSocket handling, uncomment the following line:
#org.apache.tomcat.websocket.level = FINE

All answers are acceptable. Thanks to everyone.

Answer 1

tomcat. Tomcat , , TLD, , . , :

• . , , , , tomcat. org.apache.jasper.servlet.TldScanner.level = SEVERE logging.properties.

• , tomcat . :

  org.apache.jasper.compiler.TldLocationsCache.level = FINE
  org.apache.jasper.servlet.TldScanner.level = FINE
  

( ) tomcat.util.scan.StandardJarScanFilter.jarsToSkip=... tomcat_dir/conf/catalina.properties

Answer 2

FINE, FINEST ALL, , .

script, , TLD ( TOMCAT_HOME )

jar1.jar,\
jar2.jar,\
...

.properties( , \'):

#!/bin/sh
TOMCAT_HOME=/opt/tomcat
for i in `find $TOMCAT_HOME -follow -name "*jar"`
do
    jar tvf $i | grep -i tld > /dev/null
    if [ $? -ne 0 ]; then
        echo "$(basename $i),\\"
    fi
done

, , tomcat 9 , ( catalina.properties):

tomcat.util.scan.StandardJarScanFilter.jarsToSkip=\

tomcat.util.scan.StandardJarScanFilter.jarsToSkip=*.jar

( ), , TLD, :

tomcat.util.scan.StandardJarScanFilter.jarsToScan=\
log4j-web*.jar,log4j-taglib*.jar,log4javascript*.jar,slf4j-taglib*.jar

, script , , TLD:

#!/bin/sh
TOMCAT_HOME=/opt/tomcat
for i in `find $TOMCAT_HOME -follow -name "*jar"`
do
    jar tvf $i | grep -i tld > /dev/null
    if [ $? -eq 0 ]; then
        echo "$(basename $i),\\"
    fi
done

Answer 3

modify the conf \ context.xml file

<Context>
    <!-- only if you do not use jsp tag -->
    <JarScanner>
        <JarScanFilter defaultPluggabilityScan="false" defaultTldScan="false"/>
    </JarScanner>
</Context>

see: https://tomcat.apache.org/tomcat-9.0-doc/config/jar-scan-filter.html

Answer 4

the same problem, I was fixed .. I think this is a permission problem, so you need to give full access to the webapps / project folder.