Java record -77-enhanced for loop and auto-unboxing

Introduction to new features in JDK5.0:

generic type (generics);

Enhanced "for" loops (enhanced for loop);

Automatic packing/automatic unpacking (autoboxing/unboxing);

Type safety enumeration (type safe enums);

Static import (statically import);

Variable parameters (Var args);

Enhanced for Loop:

The addition of the For-each loop simplifies the traversal of the collection

Its syntax is as follows:

for (type Element:array) {

SYSTEM.OUT.PRINTLN (Element);

}

When iterating through a collection or array, if you need to access the index of a collection or array, you end up looping or iterating using the old-fashioned way, rather than using an enhanced for loop because it loses subscript information.

Automatic boxing/unpacking greatly facilitates the role of basic type data and their wrapper classes.

Automatic Boxing: The base type is automatically converted to the wrapper class. (int >> Integer)
Automatic unpacking: The wrapper class is automatically converted to the basic type. (Integer >> int)

Java record -77-enhanced for loop and auto-unboxing