ExpressionFilter filter = new ExpressionFilter("#[json:[0]/text]");
filter.setMuleContext(muleContext);
assertTrue(filter.accept(message));
filter.setExpression("[0]/favorited=false");
assertTrue(filter.accept(message));
filter.setExpression("[0]/truncated != true");
assertFalse(filter.accept(message));
filter.setExpression("[0]/source=null");