src/java.xml/share/classes/com/sun/org/apache/xerces/internal/utils/XMLSecurityManager.java

*** 25,34 ****
--- 25,36 ----
  
  package com.sun.org.apache.xerces.internal.utils;
  
  import com.sun.org.apache.xerces.internal.impl.Constants;
  import com.sun.org.apache.xerces.internal.util.SecurityManager;
+ import java.util.concurrent.CopyOnWriteArrayList;
+ import org.xml.sax.SAXException;
  
  /**
   * This class manages standard and implementation-specific limitations.
   *
   */
*** 494,503 ****
--- 496,522 ----
              }
          }
  
      }
  
+     // Array list to store printed warnings for each SAX parser used
+     private static final CopyOnWriteArrayList<String> printedWarnings = new CopyOnWriteArrayList<>();
+ 
+     /**
+      * Prints out warnings if a parser does not support the specified feature/property.
+      *
+      * @param parserClassName the name of the parser class
+      * @param propertyName the property name
+      * @param exception the exception thrown by the parser
+      */
+     public static void printWarning(String parserClassName, String propertyName, SAXException exception) {
+         String key = parserClassName+":"+propertyName;
+         if (printedWarnings.addIfAbsent(key)) {
+             System.err.println( "Warning: "+parserClassName+": "+exception.getMessage());
+         }
+     }
+ 
      /**
       * Read from system properties, or those in jaxp.properties
       *
       * @param property the type of the property
       * @param sysPropertyName the name of system property