我已经编写了一个自定义的tomcat阀门来解析HTTP标头并使用它们进行身份验证。该阀通过扩展AuthenticatorBase来工作。我编译了它，并将其放在$
CATALINA_HOME / lib中。这是代码：

    public class TomcatLogin extends AuthenticatorBase {

        private String[] roleNames = null;
        private String ivcreds = null;
        private String ivuser = null;
        private String ivgroups = null;
        private GenericPrincipal principal = null;

        // Constructor defers to super class (Authenticator base)
        public TomcatLogin(){
            super();
        }

        protected boolean doAuthenticate(Request request, HttpServletResponse response)
        {
            List<String> groupsList = null;

            System.out.println("Obtaining Headers from Request");
            try {
                ivuser = request.getHeader("iv-user");
                ivcreds = request.getHeader("iv-creds");
                ivgroups = request.getHeader("iv-groups");
            } catch(Exception e) {
                e.printStackTrace();
            }

            // Require all header credentials for proper authentication
            if(ivuser == null || ivcreds == null || ivgroups == null)
                return false;

            // Split ivgroups by comma seporated value
            // Then remove head and tail quotation marks
            roleNames = ivgroups.split(",");
            for(int i=0; i<roleNames.length; i++){
                roleNames[i] = roleNames[i].substring(1, roleNames[i].length()-1 );
                groupsList.add(roleNames[i]);
            }

            principal = new GenericPrincipal(ivuser, ivcreds, groupsList);
            request.setUserPrincipal(principal);

            return true;
        }

        public String getAuthMethod() {
            return "HTTPAuthenticator";
        }

    }

然后，我告诉Tomcat使用server.xml中的阀门。扩展AuthenticatorBase
的文档说，
使用此类时，其所属的上下文（或层次结构中的父容器）必须具有关联的领域，该领域可用于验证用户并枚举已分配给他们的角色
。我以为我已经正确配置了它，但是它抛出了错误并且Tomcat无法启动。这是server.xml配置：

    <?xml version="1.0" encoding="UTF-8"?>
    ...
      <Server>
        <Service name="Catalina">
          <Engine name="Catalina" defaultHost="localhost">
            <Realm className="org.apache.catalina.realm.LockOutRealm">
              <Realm className="org.apache.catalina.realm.UserDatabaseRealm" 
                     resourceName="UserDatabase"/>
            </Realm>

            <!-- Here is my valve -->
            <Valve className="package.of.my.custom.valve.TomcatLogin" />

            <Host ... >
               ...
            </Host>
          </Engine>
        </Service>
      </Server>

这是我收到的错误消息：

10-Jan-2019 10:11:03.576 SEVERE [main] org.apache.tomcat.util.digester.Digester.endElement End event threw exception
 java.lang.reflect.InvocationTargetException
... A bunch of useless stacktrace
Caused by: java.lang.IllegalArgumentException: Configuration error:  Must be attached to a Context at org.apache.catalina.authenticator.AuthenticatorBase.setContainer(AuthenticatorBase.java:278)
at org.apache.catalina.core.StandardPipeline.addValve(StandardPipeline.java:335)
at org.apache.catalina.core.ContainerBase.addValve(ContainerBase.java:1133)
    ... 27 more

10-Jan-2019 10:11:03.579 WARNING [main] org.apache.catalina.startup.Catalina.load Catalina.start using conf/server.xml: Error at (107, 82) : Configuration error:  Must be attached to a Context
10-Jan-2019 10:11:03.579 SEVERE [main] org.apache.catalina.startup.Catalina.start Cannot start server. Server instance is not configured.

我认为我的阀门是正确编写的，所以我想问题出在配置中。不知道为什么没有附加上下文。有任何想法吗？

编辑： 我尝试将阀门放入我的应用程序中META-INF/context.xml（因为没有开始，所以我必须制造一个）。这里是：

<?xml version="1.0"?>
<Context>
    <Valve className="package.of.my.custom.valve.TomcatLogin" />
</Context>

然后，服务器启动，但是无法部署任何应用程序。我收到了与IBM阀门类似的错误，该阀门最初是在无法从中找到AuthenticatorBase类的自定义实现中尝试使用的catalina.jar。这是SEVERE我遇到的错误：

    10-Jan-2019 15:34:06.673 SEVERE [main] org.apache.catalina.core.ContainerBase.addChildInternal ContainerBase.addChild: start:
    org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/sample-DB]]
...
Stacktrace info
...
        at org.apache.catalina.util.LifecycleBase.handleSubClassException(LifecycleBase.java:441)
    Caused by: java.lang.ExceptionInInitializerError
        at org.apache.tomcat.util.digester.Digester.startDocument(Digester.java:1102)
    Caused by: java.lang.NullPointerException
        at java.nio.charset.Charset.put(Charset.java:538)
...
Stacktrace
...
    10-Jan-2019 15:34:06.688 INFO [main] org.apache.catalina.startup.HostConfig.deployWAR Deployment of web application archive [/fmac/deploy/sample.war] has finished in [11] ms
    10-Jan-2019 15:34:06.689 INFO [main] org.apache.catalina.startup.HostConfig.deployWAR Deploying web application archive [/fmac/deploy/sample-auth.war]
    10-Jan-2019 15:34:06.692 SEVERE [main] org.apache.tomcat.util.digester.Digester.startElement Begin event threw error
    java.lang.NoClassDefFoundError: org/apache/catalina/authenticator/AuthenticatorBase
...
Stacktrace
The Error Below is the most confusing one. How can it not find this class?
...
    Caused by: java.lang.ClassNotFoundException: org.apache.catalina.authenticator.AuthenticatorBase
        at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
...
Stacktrace
...
    10-Jan-2019 15:34:13.823 SEVERE [https-jsse-nio2-8443-exec-3] org.apache.coyote.http11.Http11Processor.service Error processing request
    java.lang.NoClassDefFoundError: Could not initialize class
org.apache.tomcat.util.buf.B2CConverter
        at org.apache.catalina.connector.CoyoteAdapter.convertURI(CoyoteAdapter.java:1072)