4.6. Create a Custom Valve

Procedure 4.3. Create a Custom Valve

1. Create the Valve class

   Create a subclass of org.apache.catalina.valves.ValveBase.

   package org.jboss.samplevalves;
   
   import org.apache.catalina.valves.ValveBase;
   import org.apache.catalina.connector.Request;
   import org.apache.catalina.connector.Response;
   
   public class RestrictedUserAgentsValve extends ValveBase {
   
   }

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2. Implement the invoke method

   The invoke() method is called when this valve is executed in the pipeline. The request and response objects are passed as parameters. Perform any processing and modification of the request and response here.

   public void invoke(Request request, Response response)
   {
   
   }

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3. Invoke the next pipeline step

   The last thing the invoke method must do is invoke the next step of the pipeline and pass the modified request and response objects along. This is done using the getNext().invoke() method

   getNext().invoke(request, response);

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4. Optional: Specify parameters

   If the valve must be configurable, enable this by adding a parameter. Do this by adding an instance variable and a setter method for each parameter.

   private String restrictedUserAgents = null;
   
   public void setRestricteduserAgents(String mystring) 
   {
      this.restrictedUserAgents = mystring;
   }

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