如何修复Tomcat 9.0.0M10中的“已扫描但未发现TLD的罐子”

Question

我是JavaEE新手，尝试使用ServletContextListener，侦听器的工作是连接到数据库BLABLA。当我试图启动服务器（Tomcat 9）时，它被卡在：

“信息：至少有一个JAR已扫描TLD，但未包含TLD。为此记录器启用调试日志记录，以获取已扫描但未找到TLD的JAR的完整列表。在扫描过程中跳过不需要的JAR可以缩短启动时间和JSP编译时间。”

所以我在“日志属性文件”中更改了一些属性，如下所示：

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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

所有答案都可以接受。谢谢大家。

Answer 1

更改conf\context.xml文件

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

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

Answer 2

无需将日志记录设置为FINE、FINEST或ALL来查找要排除的所有jar。

这里有一个脚本，它找到所有不包含TLD的罐子（更改TOMCAT_HOME变量以匹配您的安装），并在表单上输出一个列表

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

可以粘贴到catalina中。属性（省略最后的“，\”）：

#!/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

但是，如果我得到正确的通知，Tomcat9中有可能通过更改（在catalina.properties中）来排除所有JAR：

tomcat.util.scan.StandardJarScanFilter.jarsToSkip=\

到

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

（在下面的行中注释掉列表），然后通过更改来覆盖包含顶级域名的罐子的决定：

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

并添加通过修改上面的脚本获得的列表，列出确实包含TLD的罐：

#!/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

这不是tomcat中的bug或任何类型的问题。Tomcat只是通知您，有些JAR不包含TLD，您可以将它们添加到扫描仪的跳过列表中，以提高启动性能。所以你有两个选择：

>

你完全可以忽略这个暗示。然而，如果它让您感到烦恼，您可以将特定的记录器设置为更高的日志记录级别，从而防止tomcat对其进行日志记录。只需添加org。阿帕奇。贾斯珀。servlet。TldScanner。级别=严重至日志记录结束。财产。

启用调试日志记录，使tomcat列出这些罐并将它们添加到跳过列表中。设置：

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

并将打印的jar名称（不带路径）添加到tomcat。util。扫描标准过滤器。jarsToSkip= 在tomcat_dir/conf/catalina中。性质