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。
Security functions help you to protect your programs and data from harm, to keep data shielded and private, and to deploy new applications in security-aware runtime environments.安全功能可帮助您保护程序和数据免受伤害，保持数据屏蔽和私有，并在具有安全意识的运行时环境中部署新的应用程序。
Java also provides several tools to help you to manage access to system resources; to create, store and maintain encrypted public and private passwords (key pairs) and certificates; and to create and sign jarfiles during the deployment process.Java还提供了几个工具来帮助您管理对系统资源的访问；创建、存储和维护加密的公共和私人密码（密钥对）和证书；并在部署过程中创建和签署jar文件。