How to infer Java14 enhanced instanceOf types
This article introduces how to infer the type of Java14 enhanced instanceOf. The content is very detailed. Interested friends can use it for reference. I hope it will be helpful to you.
Instanceof in Java is used to determine whether the type of object is the target type. If true is returned, false is not returned.
Before Java 14, examples were as follows:
If (obj instanceof String) {
String str = (String) obj
Str.contains ("A")
} else {
Str = ""
}
Obj instanceof String is already true. In the following code, we still need to clearly define a new variable and do a strong type conversion.
Java 14 introduces pattern matching to instanceof. The modified code is as follows:
If (! (obj instanceof String str)) {
Str.contains ("A")
} else {
Str = ""
}
Once str is defined, it can be used in subsequent code, eliminating the need for explicit type conversions.
You can continue to add judgment conditions.
If (obj instanceof String str & & str.contains ("A")) {
System.out.println (str)
}
If (obj instanceof String str | | str.contains ("A")) {
System.out.println (str)
} this is the end of the inference about how to enhance the instanceOf type of Java14. I hope the above content can be of some help and learn more knowledge. If you think the article is good, you can share it for more people to see.
