Java编程思想（第4版）

《THINKING IN JAVA》中文版.............................................................................................................................................1 写在前面的话..............................................................................................................................................................................6 引言................................................................................................................................................................................................8 1. 前提......................................................................................................................................................................................8 2. Java 的学习.........................................................................................................................................................................8 3. 目标......................................................................................................................................................................................8 4. 联机文档.............................................................................................................................................................................9 5. 章节......................................................................................................................................................................................9 6. 练习....................................................................................................................................................................................12 7. 多媒体CD-ROM .............................................................................................................................................................12 8. 源代码................................................................................................................................................................................12 9. 编码样式...........................................................................................................................................................................14 10. Java版本.........................................................................................................................................................................14 11. 课程和培训.....................................................................................................................................................................14 12. 错误..................................................................................................................................................................................14 13. 封面设计 .........................................................................................................................................................................15 14. 致谢..................................................................................................................................................................................15 第 1 章 对象入门.......................................................................................................................................................................27 1.1 抽象的进步.....................................................................................................................................................................27 1.2 对象的接口.....................................................................................................................................................................28 1.3 实现方案的隐藏............................................................................................................................................................29 1.4 方案的重复使用............................................................................................................................................................30 1.5 继承：重新使用接口...................................................................................................................................................30 1.5.1 改善基础类..............................................................................................................................................................30 1.5.2 等价与类似关系.....................................................................................................................................................31 1.6 多形对象的互换使用...................................................................................................................................................31 1.6.1 动态绑定..................................................................................................................................................................32 1.6.2 抽象的基础类和接口............................................................................................................................................32 1.7 对象的创建和存在时间...............................................................................................................................................33 1.7.1 集合与继承器.........................................................................................................................................................33 1.7.2 单根结构..................................................................................................................................................................34 1.7.3 集合库与方便使用集合........................................................................................................................................35 1.7.4 清除时的困境：由谁负责清除？......................................................................................................................35 1.8 违例控制：解决错误...................................................................................................................................................36 1.9 多线程..............................................................................................................................................................................37 1.10 永久性 ...........................................................................................................................................................................37 1.11 Java和因特网..............................................................................................................................................................37 1.11.1 什么是 Web？......................................................................................................................................................37 1.11.2 客户端编程（注释⑧） .....................................................................................................................................38 1.11.3 服务器端编程.......................................................................................................................................................41 1.11.4 一个独立的领域：应用程序.............................................................................................................................41 1.12 分析和设计...................................................................................................................................................................42 1.12.1 不要迷失................................................................................................................................................................42 1.12.2 阶段 0：拟出一个计划....................................................................................................................................... 42 1.12.3 阶段 1：要制作什么？....................................................................................................................................... 43 1.12.4 阶段 2：如何构建？...........................................................................................................................................43 1.12.5 阶段 3：开始创建 ...............................................................................................................................................44 1.12.6 阶段 4：校订 ........................................................................................................................................................44 1.12.7 计划的回报 ...........................................................................................................................................................45 1.13 Java还是C++？........................................................................................................................................................45 18 第 2 章 一切都是对象..............................................................................................................................................................46 2.1 用句柄操纵对象............................................................................................................................................................46 2.2 所有对象都必须创建...................................................................................................................................................46 2.2.1 保存到什么地方.....................................................................................................................................................46 2.2.2 特殊情况：主要类型............................................................................................................................................47 2.2.3 Java的数组 .............................................................................................................................................................48 2.3 绝对不要清除对象 .......................................................................................................................................................48 2.3.1 作用域 ......................................................................................................................................................................48 2.3.2 对象的作用域.........................................................................................................................................................49 2.4 新建数据类型：类 .......................................................................................................................................................49 2.4.1 字段和方法..............................................................................................................................................................49 2.5 方法、自变量和返回值...............................................................................................................................................50 2.5.1 自变量列表..............................................................................................................................................................51 2.6 构建Java 程序...............................................................................................................................................................52 2.6.1 名字的可见性.........................................................................................................................................................52 2.6.2 使用其他组件.........................................................................................................................................................52 2.6.3 static 关键字............................................................................................................................................................ 52 2.7 我们的第一个 Java 程序.............................................................................................................................................53 2.8 注释和嵌入文档............................................................................................................................................................55 2.8.1 注释文档..................................................................................................................................................................56 2.8.2 具体语法..................................................................................................................................................................56 2.8.3 嵌入 HTML.............................................................................................................................................................56 2.8.4 @see：引用其他类...............................................................................................................................................57 2.8.5 类文档标记..............................................................................................................................................................57 2.8.6 变量文档标记.........................................................................................................................................................57 2.8.7 方法文档标记.........................................................................................................................................................57 2.8.8 文档示例..................................................................................................................................................................58 2.9 编码样式 .........................................................................................................................................................................59 2.10 总结................................................................................................................................................................................59 2.11 练习................................................................................................................................................................................59 第 3 章 控制程序流程..............................................................................................................................................................60 3.1 使用Java 运算符 ..........................................................................................................................................................60 3.1.1 优先级 ......................................................................................................................................................................60 3.1.2 赋值...........................................................................................................................................................................60 3.1.3 算术运算符..............................................................................................................................................................62 3.1.4 自动递增和递减.....................................................................................................................................................64 3.1.5 关系运算符..............................................................................................................................................................65 3.1.6 逻辑运算符..............................................................................................................................................................66 3.1.7 按位运算符..............................................................................................................................................................68 3.1.8 移位运算符..............................................................................................................................................................68 3.1.9 三元 if -else运算符................................................................................................................................................71 3.1.10 逗号运算符 ...........................................................................................................................................................72 3.1.11 字串运算符+.........................................................................................................................................................72 3.1.12 运算符常规操作规则..........................................................................................................................................72 3.1.13 造型运算符 ...........................................................................................................................................................73 3.1.14 Java 没有“sizeof” ............................................................................................................................................74 3.1.15 复习计算顺序.......................................................................................................................................................75 3.1.16 运算符总结 ...........................................................................................................................................................75 3.2 执行控制 .........................................................................................................................................................................84 3.2.1 真和假......................................................................................................................................................................84 3.2.2 if-else........................................................................................................................................................................84 3.2.3 反复...........................................................................................................................................................................85 19 3.2.4 do-while....................................................................................................................................................................85 3.2.5 for..............................................................................................................................................................................86 3.2.6 中断和继续..............................................................................................................................................................87 3.2.7 开关...........................................................................................................................................................................91 3.3 总结..................................................................................................................................................................................94 3.4 练习..................................................................................................................................................................................94 第 4 章 初始化和清除..............................................................................................................................................................95 4.1 用构建器自动初始化...................................................................................................................................................95 4.2 方法过载 .........................................................................................................................................................................96 4.2.1 区分过载方法.........................................................................................................................................................97 4.2.2 主类型的过载.........................................................................................................................................................98 4.2.3 返回值过载............................................................................................................................................................101 4.2.4 默认构建器............................................................................................................................................................102 4.2.5 this 关键字.............................................................................................................................................................102 4.3 清除：收尾和垃圾收集............................................................................................................................................105 4.3.1 finalize()用途何在................................................................................................................................................105 4.3.2 必须执行清除.......................................................................................................................................................106 4.4 成员初始化..................................................................................................................................................................108 4.4.1 规定初始化............................................................................................................................................................109 4.4.2 构建器初始化.......................................................................................................................................................111 4.5 数组初始化..................................................................................................................................................................116 4.5.1 多维数组................................................................................................................................................................119 4.6 总结...............................................................................................................................................................................121 4.7 练习...............................................................................................................................................................................121 第 5 章 隐藏实施过程...........................................................................................................................................................123 5.1 包：库单元..................................................................................................................................................................123 5.1.1 创建独一无二的包名..........................................................................................................................................124 5.1.2 自定义工具库.......................................................................................................................................................126 5.1.3 利用导入改变行为 ..............................................................................................................................................128 5.1.4 包的停用................................................................................................................................................................130 5.2 Java访问指示符 ........................................................................................................................................................130 5.2.1 “友好的”............................................................................................................................................................130 5.2.2 public：接口访问 ................................................................................................................................................131 5.2.3 private：不能接触！...........................................................................................................................................132 5.2.4 protected：“友好的一种”..............................................................................................................................133 5.3 接口与实现..................................................................................................................................................................134 5.4 类访问...........................................................................................................................................................................135 5.5 总结...............................................................................................................................................................................136 5.6 练习...............................................................................................................................................................................137 第 6 章 类再生 ........................................................................................................................................................................139 6.1 合成的语法..................................................................................................................................................................139 6.2 继承的语法..................................................................................................................................................................141 6.2.1 初始化基础类.......................................................................................................................................................143 6.3 合成与继承的结合 ....................................................................................................................................................145 6.3.1 确保正确的清除...................................................................................................................................................146 6.3.2 名字的隐藏............................................................................................................................................................148 6.4 到底选择合成还是继承............................................................................................................................................149 6.5 protected.......................................................................................................................................................................150 6.6 累积开发 ......................................................................................................................................................................151 6.7 上溯造型 ......................................................................................................................................................................151 6.7.1 何谓“上溯造型”？..........................................................................................................................................152 6.8 final关键字..................................................................................................................................................................152 6.8.1 final 数据................................................................................................................................................................152 20 6.8.2 final 方法................................................................................................................................................................155 6.8.3 final 类....................................................................................................................................................................156 6.8.4 final 的注意事项 ..................................................................................................................................................156 6.9 初始化和类装载.........................................................................................................................................................157 6.9.1 继承初始化............................................................................................................................................................157 6.10 总结.............................................................................................................................................................................158 6.11 练习.............................................................................................................................................................................159 第 7 章 多形性 ........................................................................................................................................................................160 7.1 上溯造型 ......................................................................................................................................................................160 7.1.1 为什么要上溯造型 ..............................................................................................................................................161 7.2 深入理解 ......................................................................................................................................................................162 7.2.1 方法调用的绑定...................................................................................................................................................163 7.2.2 产生正确的行为...................................................................................................................................................163 7.2.3 扩展性 ....................................................................................................................................................................165 7.3 覆盖与过载..................................................................................................................................................................168 7.4 抽象类和方法 .............................................................................................................................................................169 7.5 接口...............................................................................................................................................................................172 7.5.1 Java的“多重继承”..........................................................................................................................................174 7.5.2 通过继承扩展接口 ..............................................................................................................................................176 7.5.3 常数分组................................................................................................................................................................177 7.5.4 初始化接口中的字段..........................................................................................................................................178 7.6 内部类...........................................................................................................................................................................179 7.6.1 内部类和上溯造型 ..............................................................................................................................................180 7.6.2 方法和作用域中的内部类.................................................................................................................................181 7.6.3 链接到外部类.......................................................................................................................................................186 7.6.4 static 内部类..........................................................................................................................................................187 7.6.5 引用外部类对象...................................................................................................................................................189 7.6.6 从内部类继承.......................................................................................................................................................190 7.6.7 内部类可以覆盖吗？..........................................................................................................................................190 7.6.8 内部类标识符.......................................................................................................................................................192 7.6.9 为什么要用内部类：控制框架.........................................................................................................................192 7.7 构建器和多形性.........................................................................................................................................................198 7.7.1 构建器的调用顺序 ..............................................................................................................................................198 7.7.2 继承和finalize()...................................................................................................................................................199 7.7.3 构建器内部的多形性方法的行为....................................................................................................................202 7.8 通过继承进行设计 ....................................................................................................................................................204 7.8.1 纯继承与扩展.......................................................................................................................................................205 7.8.2 下溯造型与运行期类型标识.............................................................................................................................206 7.9 总结...............................................................................................................................................................................208 7.10 练习.............................................................................................................................................................................208 第 8 章 对象的容纳................................................................................................................................................................209 8.1 数组...............................................................................................................................................................................209 8.1.1 数组和第一类对象 ..............................................................................................................................................209 8.1.2 数组的返回............................................................................................................................................................212 8.2 集合...............................................................................................................................................................................213 8.2.1 缺点：类型未知...................................................................................................................................................213 8.3 枚举器（反复器） ....................................................................................................................................................217 8.4 集合的类型..................................................................................................................................................................220 8.4.1 Vector.....................................................................................................................................................................220 8.4.2 BitSet......................................................................................................................................................................221 8.4.3 Stack.......................................................................................................................................................................222 8.4.4 Hashtable................................................................................................................................................................223 8.4.5 再论枚举器............................................................................................................................................................228 21 8.5 排序...............................................................................................................................................................................229 8.6 通用集合库..................................................................................................................................................................232 8.7 新集合...........................................................................................................................................................................233 8.7.1 使用 Collections...................................................................................................................................................235 8.7.2 使用 Lists...............................................................................................................................................................238 8.7.3 使用 Sets................................................................................................................................................................242 8.7.4 使用Maps..............................................................................................................................................................244 8.7.5 决定实施方案.......................................................................................................................................................247 8.7.6 未支持的操作.......................................................................................................................................................253 8.7.7 排序和搜索............................................................................................................................................................255 8.7.8 实用工具................................................................................................................................................................259 8.8 总结...............................................................................................................................................................................261 8.9 练习...............................................................................................................................................................................262 第 9 章 违例差错控制...........................................................................................................................................................263 9.1 基本违例 ......................................................................................................................................................................263 9.1.1 违例自变量............................................................................................................................................................264 9.2 违例的捕获..................................................................................................................................................................264 9.2.1 try 块.......................................................................................................................................................................264 9.2.2 违例控制器............................................................................................................................................................265 9.2.3 违例规范................................................................................................................................................................265 9.2.4 捕获所有违例.......................................................................................................................................................266 9.2.5 重新“掷”出违例 ..............................................................................................................................................267 9.3 标准Java 违例............................................................................................................................................................270 9.3.1 RuntimeException的特殊情况 .........................................................................................................................270 9.4 创建自己的违例.........................................................................................................................................................271 9.5 违例的限制..................................................................................................................................................................274 9.6 用 finally 清除.............................................................................................................................................................276 9.6.1 用 finally 做什么 ..................................................................................................................................................277 9.6.2 缺点：丢失的违例 ..............................................................................................................................................279 9.7 构建器...........................................................................................................................................................................280 9.8 违例匹配 ......................................................................................................................................................................283 9.8.1 违例准则................................................................................................................................................................284 9.9 总结...............................................................................................................................................................................284 9.10 练习.............................................................................................................................................................................284 第 10 章 JAVA IO 系统.........................................................................................................................................................285 10.1 输入和输出................................................................................................................................................................285 10.1.1 InputStream的类型...........................................................................................................................................285 10.1.2 OutputStream的类型 ........................................................................................................................................286 10.2 增添属性和有用的接口 .........................................................................................................................................286 10.2.1 通过 FilterInputStream从 InputStream里读入数据...................................................................................287 10.2.2 通过 FilterOutputStream向 OutputStream 里写入数据.............................................................................287 10.3 本身的缺陷：RandomAccessFile.........................................................................................................................288 10.4 File类.........................................................................................................................................................................288 10.4.1 目录列表器 .........................................................................................................................................................288 10.4.2 检查与创建目录.................................................................................................................................................292 10.5 IO 流的典型应用......................................................................................................................................................294 10.5.1 输入流 ..................................................................................................................................................................296 10.5.2 输出流 ..................................................................................................................................................................298 10.5.3 快捷文件处理.....................................................................................................................................................298 10.5.4 从标准输入中读取数据....................................................................................................................................300 10.5.5 管道数据流 .........................................................................................................................................................300 10.6 StreamTokenizer........................................................................................................................................................300 22 10.6.1 StringTokenizer..................................................................................................................................................303 10.7 Java 1.1 的IO 流......................................................................................................................................................305 10.7.1 数据的发起与接收 ............................................................................................................................................305 10.7.2 修改数据流的行为 ............................................................................................................................................306 10.7.3 未改变的类 .........................................................................................................................................................306 10.7.4 一个例子..............................................................................................................................................................307 10.7.5 重导向标准 IO....................................................................................................................................................310 10.8 压缩.............................................................................................................................................................................311 10.8.1 用 GZIP 进行简单压缩.....................................................................................................................................311 10.8.2 用 Zip 进行多文件保存....................................................................................................................................312 10.8.3 Java 归档（jar）实用程序...............................................................................................................................314 10.9 对象序列化................................................................................................................................................................315 10.9.1 寻找类 ..................................................................................................................................................................318 10.9.2 序列化的控制.....................................................................................................................................................319 10.9.3 利用“持久性”.................................................................................................................................................326 10.10 总结...........................................................................................................................................................................332 10.11 练习...........................................................................................................................................................................332 第 11 章 运行期类型鉴定.....................................................................................................................................................333 11.1 对 RTTI 的需要.........................................................................................................................................................333 11.1.1 Class对象............................................................................................................................................................334 11.1.2 造型前的检查.....................................................................................................................................................337 11.2 RTTI 语法...................................................................................................................................................................342 11.3 反射：运行期类信息..............................................................................................................................................343 11.3.1 一个类方法提取器 ............................................................................................................................................344 11.4 总结.............................................................................................................................................................................347 11.5 练习.............................................................................................................................................................................348 第 12 章 传递和返回对象.....................................................................................................................................................349 12.1 传递句柄....................................................................................................................................................................349 12.1.1 别名问题..............................................................................................................................................................349 12.2 制作本地副本...........................................................................................................................................................351 12.2.1 按值传递..............................................................................................................................................................351 12.2.2 克隆对象..............................................................................................................................................................352 12.2.3 使类具有克隆能力 ............................................................................................................................................353 12.2.4 成功的克隆 .........................................................................................................................................................353 12.2.5 Object.clone()的效果 ........................................................................................................................................355 12.2.6 克隆合成对象.....................................................................................................................................................356 12.2.7 用 Vector进行深层复制...................................................................................................................................358 12.2.8 通过序列化进行深层复制...............................................................................................................................359 12.2.9 使克隆具有更大的深度....................................................................................................................................361 12.2.10 为什么有这个奇怪的设计.............................................................................................................................362 12.3 克隆的控制................................................................................................................................................................363 12.3.1 副本构建器 .........................................................................................................................................................366 12.4 只读类 ........................................................................................................................................................................369 12.4.1 创建只读类 .........................................................................................................................................................370 12.4.2 “一成不变”的弊端........................................................................................................................................371 12.4.3 不变字串..............................................................................................................................................................373 12.4.4 String和 StringBuffer 类..................................................................................................................................374 12.4.5 字串的特殊性.....................................................................................................................................................376 12.5 总结.............................................................................................................................................................................376 12.6 练习.............................................................................................................................................................................376 第十三章 创建窗口和程序片..............................................................................................................................................378 13.1 为何要用 AWT ？......................................................................................................................................................378 23 13.2 基本程序片................................................................................................................................................................379 13.2.1 程序片的测试.....................................................................................................................................................380 13.2.2 一个更图形化的例子........................................................................................................................................381 13.2.3 框架方法的演示.................................................................................................................................................381 13.3 制作按钮....................................................................................................................................................................382 13.4 捕获事件....................................................................................................................................................................382 13.5 文本字段....................................................................................................................................................................384 13.6 文本区域....................................................................................................................................................................385 13.7 标签.............................................................................................................................................................................386 13.8 复选框 ........................................................................................................................................................................387 13.9 单选钮 ........................................................................................................................................................................388 13.10 下拉列表..................................................................................................................................................................389 13.11 列表框 ......................................................................................................................................................................390 13.11.1 handleEvent()....................................................................................................................................................391 13.12 布局的控制 .............................................................................................................................................................393 13.12.1 FlowLayout.......................................................................................................................................................393 13.12.2 BorderLayout....................................................................................................................................................393 13.12.3 GridLayout........................................................................................................................................................394 13.12.4 CardLayout........................................................................................................................................................394 13.12.5 GridBagLayout.................................................................................................................................................396 13.13 action 的替代品......................................................................................................................................................396 13.14 程序片的局限.........................................................................................................................................................400 13.14.1 程序片的优点...................................................................................................................................................401 13.15 视窗化应用 .............................................................................................................................................................401 13.15.1 菜单....................................................................................................................................................................401 13.15.2 对话框................................................................................................................................................................404 13.16 新型AWT.................................................................................................................................................................408 13.16.1 新的事件模型...................................................................................................................................................409 13.16.2 事件和接收者类型 ..........................................................................................................................................410 13.16.3 用 Java 1.1 AWT制作窗口和程序片..........................................................................................................414 13.16.4 再研究一下以前的例子 .................................................................................................................................416 13.16.5 动态绑定事件...................................................................................................................................................431 13.16.6 将事务逻辑与 UI逻辑区分开 ......................................................................................................................433 13.16.7 推荐编码方法...................................................................................................................................................435 13.17 Java 1.1 用户接口 API..........................................................................................................................................448 13.17.1 桌面颜色...........................................................................................................................................................448 13.17.2 打印....................................................................................................................................................................448 13.17.3 剪贴板................................................................................................................................................................454 13.18 可视编程和 Beans.................................................................................................................................................456 13.18.1 什么是 Bean......................................................................................................................................................457 13.18.2 用 Introspector提取BeanInfo.......................................................................................................................458 13.18.3 一个更复杂的 Bean........................................................................................................................................463 13.18.4 Bean的封装......................................................................................................................................................465 13.18.5 更复杂的 Bean 支持........................................................................................................................................466 13.18.6 Bean更多的知识 .............................................................................................................................................466 13.19 Swing 入门（注释⑦）.........................................................................................................................................467 13.19.1 Swing有哪些优点...........................................................................................................................................467 13.19.2 方便的转换 .......................................................................................................................................................467 13.19.3 显示框架...........................................................................................................................................................468 13.19.4 工具提示...........................................................................................................................................................469 13.19.5 边框..........................................................