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regextomcaturl-pattern

What is the meaning of the leading slash / in Tomcat's <url-pattern>?

I know I cannot use regular expressions for the <url-pattern> of a filter-mapping, but is it possible to use a directory pattern to specify any url containing the word myuniqws as in:

https://my.hostname.org/myuniqws/myport/soap?wsdl

I am thinking of perhaps this would be the correct syntax:

<url-pattern>/*myuniqws*</url-pattern>

but I have not been able to find documentation for the exact rule of Tomcat's <url-pattern> syntax.

Will the above regex work as I desire?

Update:

Thanks to the answer below, I discovered the following section in the Java Servlet Specification, which basically answers my questions.

12.2 Specification of Mappings

In the Web application deployment descriptor, the following syntax is used to define mappings:

  • A string beginning with a ‘/’ character and ending with a ‘/*’ suffix is used for path mapping.
  • A string beginning with a ‘*.’ prefix is used as an extension mapping.
  • The empty string ("") is a special URL pattern that exactly maps to the application's context root, i.e., requests of the form http://host:port/<contextroot>/. In this case the path info is ’/’ and the servlet path and context path is empty string (““).
  • A string containing only the ’/’ character indicates the "default" servlet of the application. In this case the servlet path is the request URI minus the context path and the path info is null.
  • All other strings are used for exact matches only.

If the effective web.xml (after merging information from fragments and annotations) contains any url-patterns that are mapped to multiple servlets then the deployment must fail.

Solution

  • Presumably, you mean the <url-pattern> for filter mappings in web.xml. You might not know this, but web.xml is defined as part of the Java Servlet Specification. You can find full documentation for the 3.1 version (currently, the latest and greatest) here:

    https://jcp.org/aboutJava/communityprocess/final/jsr340/index.html

    If you read section 12.2 ("Specification of Mappings") you can see exactly what kinds of patterns are recognized, including the prefix-mapping you are requesting above.

    EDIT 2014-11-04: You should know that CATALINA_HOME/conf/web.xml (or CATALINA_BASE/conf/web.xml if you have one) is the default configuration for all web applications deployed on Tomcat and that your webapp's WEB-INF/web.xml is the configuration specific for your own web application. Both of these files should have the following xmlns statements and therefore indicate to you (by their URIs) that they are covered by the Java Servlet Specification (or at least Java EE, which includes the servlet spec):

    <web-app xmlns="http://java.sun.com/xml/ns/javaee"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
                      http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
  version="3.0">