The Java Tutorials have been written for JDK 8.Java教程是为JDK 8编写的。Examples and practices described in this page don't take advantage of improvements introduced in later releases and might use technology no longer available.本页中描述的示例和实践没有利用后续版本中引入的改进，并且可能使用不再可用的技术。See Java Language Changes for a summary of updated language features in Java SE 9 and subsequent releases.有关Java SE 9及其后续版本中更新的语言特性的摘要，请参阅Java语言更改。
See JDK Release Notes for information about new features, enhancements, and removed or deprecated options for all JDK releases.有关所有JDK版本的新功能、增强功能以及已删除或不推荐的选项的信息，请参阅JDK发行说明。
An interface declaration can contain method signatures, default methods, static methods and constant definitions. 接口声明可以包含方法签名、默认方法、静态方法和常量定义。The only methods that have implementations are default and static methods.唯一具有实现的方法是默认方法和静态方法。
A class that implements an interface must implement all the methods declared in the interface.实现接口的类必须实现接口中声明的所有方法。
An interface name can be used anywhere a type can be used.接口名称可以在任何可以使用类型的地方使用。