Java复习提纲(不完全).docxVIP

Chapter 1 Introduction to JavaWednesday, June 18, 201416:54?Features of Java Simple 简单Object-oriented 面向对象的Distributed 分布式的Interpreted 解析性的Robust 健壮的compile-time error checking 编译时期错误检查not support memory pointers 不支持内存指针automatic garbage collection 自动垃圾回收Secure 安全architecture neutral 体系结构中立Portable 便携High performance 高性能Multithreaded 多线程Dynamic language 动态语言?A typical Java development environmentJava programs normally undergo five phases: Edit, Compile, Load, Verify, Execute五步骤：编辑、编译、加载、验证、执行。?To test-drive a Java application using the command line编译Java时用javac xxx.java命令编译目录下全部文件javac *.java命令运行Java时用java xxx.class命令 .class（扩展名可以省略）??Three edition for Java SDKJava SDK Standard Edition（J2SE) contains the basic core Java classes. Java SDK Micro Edition (J2ME)for developers that code to portable devices, such as a palm pilot or a cellular phone. Java SDK Enterprise Edition (J2EE) contains classes that go above and beyond J2SE ???Chapter 2 Introduction to Java ApplicationsWednesday, June 18, 201417:07To Know some convention and syntax.?To write simple Java applications.main methodpublic static void main(String[] args){}?To use input and output statements.Class Scanner ( nextInt … )OutputStream (System.out.println(…))?Java’s primitive types.boolean, byte, char, short, int, long, float, double?Basic memory concepts.Garbage collectionl 程序员无权回收内存。当一个对象没有被任何引用类型的变量引用时，该对象的内存可以被垃圾回收器自动回收；2 垃圾回收器以独立的线程异步执行，回收的时间是程序无法预计的；3 程序员可以调用System.gc()或者Runtime.gc()，提示垃圾回收器进行垃圾回收；4 垃圾回收器进行垃圾回收时，调用对象的方法finalize 析构方法。考点：1 注意条件，没有被任何引用类型的变量引用时 2 程序员无权强制回收，只能建议。 3 对象没有被回收的话就不会调用finalize方法?还有一个输入流的问题（这个要重视，虽然感觉有点偏）I/O from the Command Line命令行输入输出System.in; System.out; System.err.System.console()?1 两种Standard Streams输出流和The Console控制台2 Standard Streams:三种 Standard Input标准输入, accessed through System.in; Standard Output标准输出, accessed through System.out; Standard Error标准, accessed through System.err.3 System.in is a byte stream 字节流To use Standard Input as a character stream, wrap Sys