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
317 views
in Technique[技术] by (71.8m points)

java - What is the purpose of generics before return type

For example, in the following code

public <U extends Number> void inspect(U u){
// Some method
}

what is the purpose of (what is this line doing or how is it read) that comes just before the return type

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)

This is the syntax that makes your method (as opposed to your class) generic.

Methods of regular and generic classes can be made generic on their own type parameters. In this case, your inspect method is generic on U, which must be a type extending from Number.


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

...