package org.webslinger;

 import java.io.IOException;

 import javax.servlet.ServletException;

 import org.webslinger.container.FileInfo;

 public class ReadObjectFilterCreator extends FileInfo.ReadObjectCreator {

     private final String filterAttribute;

     public ReadObjectFilterCreator(String typeAttribute, String defaultType, String filterAttribute) {

         super(typeAttribute, defaultType);

         this.filterAttribute = filterAttribute;

     }

     public Object createValue(FileInfo fi, String name) throws IOException {

         Object value = super.createValue(fi, name);

         String filter = (String) fi.getAttribute(filterAttribute);

         if (filter == null) return value;

         WebslingerServletContext wsc = fi.getContainer().getWebslingerServletContext();

         try {

             return wsc.run(wsc.resolve(filter), null, null, value);

         } catch (ServletException e) {

             throw (IOException) new IOException(e.getMessage()).initCause(e);

         }

     }

 }