Returns the elements contained by the element with the given route and having the given attribute with the given value. 
      Syntax
         
         public abstract List< IParserDocument > getChildDocumentsWithAttribute (
    String attributeName,
    String attributeValue,
    boolean addByDefault,
    String... route
)
       
      Parameters
         
         
            - 
               route – 
               The route to the element with the child elements
            
 
            - 
               attributeName – 
               The name of the attribute
            
 
            - 
               attributeValue – 
               The expected value of the attribute
            
 
            - 
               addByDefault – 
               true if element should be returned in case it does not contain the given attribute
            
 
         
       
      Returns
         List of elements as new IParser documents
      Exceptions
         
         
            - 
               IllegalArgumentException – 
               if either of the arguments is null.