jsp - java.lang.NullPointerException at javax.el.CompositeELResolver.add -


i newbie on jsp , have existing application works in tomcat 6.0.45. upgraded tomcat 9.0.0.m26. have el statement in .jsp, tomcat throws nullpointerexception when drawing page:

java.lang.nullpointerexception     java.util.objects.requirenonnull(objects.java:203)     javax.el.compositeelresolver.add(compositeelresolver.java:47)     org.apache.jasper.el.elcontextimpl.<clinit>(elcontextimpl.java:87)     org.apache.jasper.compiler.validator$validatevisitor.prepareexpression(validator.java:1619)

i have tested remove application. simplest code have come causes exception is

            <c:if test="${4.0>= 3}">this true!</c:if>

i have suspected old, outdated or jar conflicts not found solution. these versions use know:

    <dependency>         <groupid>javax.servlet.jsp</groupid>         <artifactid>javax.servlet.jsp-api</artifactid>         <version>2.3.1</version>     </dependency>     <dependency>         <groupid>javax.el</groupid>         <artifactid>javax.el-api</artifactid>         <version>3.0.0</version>     </dependency>     <dependency>         <groupid>javax.servlet</groupid>         <artifactid>javax.servlet-api</artifactid>         <version>4.0.0</version>         <scope>provided</scope>     </dependency>

what part have missed?


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