This trail covers the fundamentals of programming in the Java programming language.
这个教程涵盖了JAVA程序语言的编程基础。
Object-Oriented Programming Concepts teaches you the core concepts behind object-oriented programming: objects, messages, classes, and inheritance. This lesson ends by showing you how these concepts translate into code. Feel free to skip this lesson if you are already familiar with object-oriented programming.
面向对象编程概念教给你面向对象编程背后的核心概念：对象，消息，类和继承。这一讲之后将向你展示如何使用这些概念转化为代码。如果你已经对面向对象编程很熟悉可以跳过此讲。
Language Basics describes the traditional features of the language, including variables, arrays, data types, operators, and control flow.
语言基础描述语言的基础特征，包括变量，数组，和数据类型，操作符和控制流程。
Classes and Objects describes how to write the classes from which objects are created, and how to create and use the objects.
类和对象描述如何从已经创建的对象中写出类，和如何创建和使用对象。
Interfaces and Inheritance describes interfaces—what they are, why you would want to write one, and how to write one. This section also describes the way in which you can derive one class from another. That is, how a subclass can inherit fields and methods from a superclass. You will learn that all classes are derived from the Object class, and how to modify the methods that a subclass inherits from superclasses.
接口和继承描述接口是什么，为什么你要去写它以及如何写它。这一章节同时描述你如何从一个类生成另一个类的方式。这就是，一个子类从超类中继承属性和方法。你将学到从对象中提取的所有类，并且学会如何修改一个从超类中继承的子类的方法。
Numbers and Strings This lesson describes how to use Number and String objects The lesson also shows you how to format data for output.
数组和字符串 这一讲将描述如何使用数组和字符串，这一讲同时向你展示如何格式化数据输出。
Generics are a powerful feature of the Java programming language. They improve the type safety of your code, making more of your bugs detectable at compile time.
通用型是JAVA编程语言的强大特性。它提升了你代码中的数据类型的安全性，同时能在你编译的时候检测出更多的bug。
Packages are a feature of the Java programming language that help you to organize and structure your classes and their relationships to one another.
包是JAVA编程语言的一个特征，它将帮你组织和构架你的类及它们之间的关系。
