java新特性.txt.docVIP

java新特性.txt New features description of JDK 1.5 An important topic of JDK1.5 is to simplify development by adding new features, including generics, for-each loops, automatic packet / unpacking, enumerations, variable arguments, and static import. The use of these characteristics will help us to write more clearly, efficient, safe code. First, a brief description of various characteristics and their use 1. generic (Generic) C++ allows you to specify the element type of a collection through template technology, whereas Java has no corresponding function until 1.5. A collection can hold any type of object, and we also have to force them to type conversions when objects are taken from the collection. The tiger introduces generics, which allow you to specify the types of elements in a collection, so that you can get the advantage of type checking at strong compile type at compile time. An important topic of JDK1.5 is to simplify development by adding new features, including generics, for-each loops, automatic packet / unpacking, enumerations, variable arguments, and static import. The use of these characteristics will help us to write more clearly, efficient, safe code. First, a brief description of various characteristics and their use 1. generic (Generic) C++ allows you to specify the element type of a collection through template technology, whereas Java has no corresponding function until 1.5. A collection can hold any type of object, and we also have to force them to type conversions when objects are taken from the collection. The tiger introduces generics, which allow you to specify the types of elements in a collection, so that you can get the advantage of type checking at strong compile type at compile time. 1, CollectionString, C = new, ArrayList (); 2 c.add (new, Date ()); The compiler will give you an error: Add (java.lang.String), in, java.util.Collectionjava.lang.String, cannot, be, applied, to (java.util.Date) 2.For-Each cycle The For-Each loop has to be add