Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
481 views
in Technique[技术] by (71.8m points)

groovy - How to avoid MissingPropertyException

If an object does not have a property and I am accessing the property, we get a MissingPropertyException. Can I do something similar to safe null (?.) to guard against missing properties so it doesn't throw an exception?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

One option would be:

def result = obj.hasProperty( 'b' ) ? obj.b : null

Which would return null if the object doesn't have the property...

Another would be to add propertyMissing to your class like so:

def propertyMissing( name ) {
  null
}

This means that any missing properties would just result in null.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...