expression. 3.问题与应用（能力要求 掌握表达式的优先级 第五节Data Conversion 1.主要内容 (1)Conversion Techniques 2.基本概念和知识点 (1)Narrowing conversions (2)Widening conversions 3.问题与应用（能力要求） 掌握什么情况下用narrowing和widening conversion 第六节Interactive Programs 1.主要内容 The Scanner class 2.基本概念和知识点 The Scanner class provides methods for reading input of various types from various sources 3.问题与应用（能力要求） 掌握Scanner类的使用方法 (三)思考与实践 利用Scanner类与屏幕交互，计算表达式结果，并在屏幕输出。 (四)教学方法与手段 课堂讲授为主 第三章Using Classes and0 bjects (一)目的与要求 1.Discuss the creation of objects and the use of object reference variables. 2.Explore the services provided by the String class. 3.Describe how the Java standard class library is organized into packages. 4.Explore the services provided by the Random and Math classes. 5.Discuss wrapper classes and the concept of autoboxing. 6.Introduce components and containers used in graphical user interfaces.7 expression. 3．问题与应用（能力要求） 掌握表达式的优先级 第五节 Data Conversion 1．主要内容 (1) Conversion Techniques 2．基本概念和知识点 (1) Narrowing conversions (2) Widening conversions 3．问题与应用（能力要求） 掌握什么情况下用 narrowing 和 widening conversion 第六节 Interactive Programs 1．主要内容 The Scanner Class 2．基本概念和知识点 The Scanner class provides methods for reading input of various types from various sources. 3．问题与应用（能力要求） 掌握 Scanner 类的使用方法 （三）思考与实践 利用 Scanner 类与屏幕交互，计算表达式结果，并在屏幕输出。 （四）教学方法与手段 课堂讲授为主。 第三章 Using Classes and Objects （一）目的与要求 1．Discuss the creation of objects and the use of object reference variables. 2．Explore the services provided by the String class. 3．Describe how the Java standard class library is organized into packages. 4．Explore the services provided by the Random and Math classes. 5．Discuss wrapper classes and the concept of autoboxing. 6．Introduce components and containers used in graphical user interfaces