if( null != value )
if( null != v )
    public void encodeValue( Writer writer, Value value, String pad ) throws IOException    {        if( value instanceof Construct )        {            Construct construct = (Construct) value;            String method = construct.getMethodName();            String target = construct.getTargetExpression();                        writer.write( "\n" + pad + "<param" );            if( null != target )            {                writer.write( " class=\"" + target + "\"" );            }            if( null != method )            {                writer.write( " method=\"" + method  + "\"" );            }            if( construct.isCompound() )            {                writer.write( ">" );                Value[] values = construct.getValues();                encodeValues( writer, values, pad + "  " );                writer.write( "\n" + pad + "</param>" );            }            else            {                String v = construct.getBaseValue();                if( null != value )                {                    writer.write( " value=\"" + v  + "\"" );                }                writer.write( "/>" );            }        }        else        {            final String error =               "Value class ["               + value.getClass().getName()              + "] not supported.";            throw new IOException( error );        }    }