Spring spel ,i can't get value when the expression is like '01'

spring-expression-5.1.3.RELEASE

ExpressionParser parser = new SpelExpressionParser()
StandardEvaluationContext context = new StandardEvaluationContext();
Record record = new Record();
record.put("name","scl"); 
record.put("2","22"); 
record.put("03","33"); 
context.setRootObject(record);
parser.parseExpression("[a]").getValue(context);//11
parser.parseExpression("[2]").getValue(context);//22
parser.parseExpression("[03]").getValue(context);//null

Comment From: sbrannen

Thanks for getting in touch, but it feels like this is a question that would be better suited to Stack Overflow. As mentioned in the guidelines for contributing, we prefer to use the issue tracker only for bugs and enhancements. Feel free to update this issue with a link to the re-posted question (so that other people can find it) or add some more details if you feel this is a genuine bug.