A: Java language development history
* James Gosling (James Gosling) 1977 was awarded a bachelor's degree in Computer Science, University of Calgary, Canada, in 1983, received a doctorate in computer science from Carnegie Mellon University after graduation to work for IBM. design of the first generation of IBM workstations NeWS system, but neglected. Later, go to the Sun, in 1990, cooperation "Green Plan" and Patrick, Naughton and Mike Sheridan and others, and later developed a language called "Oak", later renamed Java.
* SUN (Stanford University Network, Stanford University Networks)
* B: the Java language version
* JDK 1.1.4 Sparkler gem 1997-09-12
* the JDK 1.1.5 Pumpkin Pumpkin 1997-12-13
* the JDK 1.1.6 Abigail Abbey Gail - woman name 1998-04-24
* the JDK 1.1.7 Brutus Brutus - Roman statesman and general 1998-09-28
* the JDK 1.1.8 Chelsea Chelsea - city 1999-04-08
* J2SE 1.2 playground playground 1998-12-04
* J2SE 1.2.1 none None 1999-03-30
* J2SE 1.2.2 cricket cricket 1999-07-08
* J2SE 1.3 Kestrel American kestrels (sǔn) 2000-05-08
* J2SE 1.3.1 Ladybird Ladybird 2001-05-17
* J2SE 1.4.0 Merlin merlin 2002-02-13
* the J2SE 1.4.1 Grasshopper grasshopper 2002-09-16
* 1.4.2 Mantis Mantis the J2SE 2003-06-26
* JAVASE 5.0 (1.5.0) Tiger Tiger
* JAVASE 5.1 (1.5.1) dragonfly dragonfly
* JAVASE 6.0 (1.6.0) Mustang Mustang
* JAVASE 7.0 (1.7.0) dolphin dolphin
* C: Java language platform
* J2SE (Java 2 platform standard Edition ) standard Edition
* is common for developers solutions for the desktop and business applications provide the technical system is the basis for the other two, you can do some development of desktop applications
* J2ME (Java 2 Platform Micro Edition ) small version
* is for the development of consumer electronics and embedded devices the solution provided
* J2EE (Java 2 Platform enterprise Edition ) enterprise Edition
* for developing applications in enterprise environments to provide a set of solutions, the technology system included techniques such as Servlet, Jsp, etc., are targeted primarily at Web applications program development
* D: Java language features
* simplicity
* explanatory
* object-oriented
* High performance
* distributed processing
* multithreading
* Robustness
* Dynamic
* Structure-neutral
* security
* open source
* Cross-platform
### 01.08_Java language basis (the principle of cross-platform Java language)
* A: What is cross-platform
* B: the principle of cross-platform Java language
* as long as needed the operating system running java applications, install a Java virtual machine (JVM Java virtual machine) can be. By the JVM is responsible for running Java programs in the system.
* C: Java language, cross-platform graphical
* write once, run anywhere (a compile, run everywhere)!
### 01.09_Java language basis (JRE and JDK Overview) (master)
* A: What is the JRE
* including Java Virtual machine (JVM Java Virtual machine) and the required core class libraries and other Java programs, if you want to develop a good run Java programs, the computer can only need to install the JRE.
* JRE: JVM + class library.
* B: What is the JDK
* the JDK is available to Java developers, which contains the java development tools, including the JRE. So install the JDK, you do not have a separate installation of the JRE.
* Where development tools: compiler tools (javac.exe) Packaging Tool (jar.exe), etc.
* JDK: JRE + JAVA development tools.
* C: Why JDK contains a JRE
* Why JDK contains a JRE it?
* End of program development, we need to run it and see the effect.
* D: JDK, JRE, JVM roles and relationships of
### 01.10_Java base language (JDK illustrates the download and installation process)
* A: Download the JDK
* a: the official website at http://www.oracle.com
* B: demo download process
* B: JDK installation
* a: fool installation
* Double-click the installer, and then all the way next to (but not recommended)
* b: the recommended way to install
* the installation path do not have Chinese or special characters such as spaces.
* All the best and the development of related software installation directory unity.
* Example: my JDK installation path
* D: \ Develop \ the Java \ jdk1.7.0_72
* When prompted to install the JRE, you can choose not to install. Recommendations or installed.
* C: demo installation process
* can first create a disk file in the folder d Develop
* then demonstrate the installation process
* C: Verify that the installation was successful
* a: through DOS commands to switch to the bin directory of JDK installation.
D *: \ Develop \ the Java \ jdk1.7.0_72 \ bin
* b: javac and then separately enter java, if something normal display, indicating that the installation was successful
### 01.11_Java language foundation (directory under the JDK installation path explanation)
* a: bin directory: the directory used to store a number of executable programs.
* If javac.exe (java compiler), java.exe (java run the tool), jar.exe (Packaging Tool) and * javadoc.exe (document generation tool) and so on.
* B: db directory: db directory is a small database.
* Start from JDK 6.0, Java cited a new member JavaDB, this is a pure Java, open source database management systems. This database is not only lightweight, but also supports all JDBC 4.0 specification, learning JDBC, no additional software to install a database, you can choose to directly use JavaDB.
* C: jre directory: "jre" is an abbreviation for the Java Runtime Environment, which means Java runtime environment. This directory is the root directory of the Java Runtime Environment, which includes the Java virtual machine, runtime class package, Java application launcher and a bin directory, but does not include a development environment development tool.
* D: include directory: JDK is due by C and C ++ implementation, so when you start the need to introduce some of the C language header files, the directory is used to store these header files.
* E: lib directory: lib library is an abbreviation, meaning Java class libraries or library file, the archive file is to use development tools.
* F: src.zip file: src.zip for the src folder of file compression, src is placed in core classes JDK source code, you can view the source code for the Java Foundation Classes through the file.
### 01.12_Java the basis of language (Java development tools introduced)
* A: notepad (Microsoft operating system comes)
* B: Editplus / Notepad ++
* C: the Eclipse
* D: MyEclipse
### 01.13_Java language basis (HelloWorld case of writing and running)
* A: define a class
* B: write the main method
* C: Write output statement
* D: Java developers to run and works
* E: compile and run
the HelloWorld {class
public static void main (String [] args) {
System.out.println ( "the HelloWorld");
}
}
### 01.14_Java Language Infrastructure (HelloWorld case FAQ)
* A: Can not find file ()
* a: the file extension hidden compilation fails
* b: wrong file name
* B: spelling problem ()
* a: class written class
* b: String written as String
* c: System written in System
* d: main written Mian
* C: matching parenthesis ()
* a: the pair of braces class body knocked off a
* b: the pair of braces method body knocked off a
* c: the pair of parentheses in the output statement knocked off a
* D: English problem ()
* a: message: error: illegal characters: \ ???? formats
* Note: java programming required basically English characters
### 01.15_Java language basis (written in the Java language format (convention))
* 1, braces to align and write in pairs
* 2, a space in front of the opening brace
* 3, encountered the opening brace to indent, Na'tab'al
*. 4, and the block between the CSA method allows the program looks clear lines
* 5, spaces between the parallel statement, for example, the statement
* 6, operators add spaces
### 01.16_Java language basis (the role and configuration path environment variable 1)
* A: problems in the bin directory under the JDK development process prone
* a: If the file is too inconvenient management
* b: remove yourself write off unneeded files, you may accidentally JDK comes with a tool to delete
* B: how to solve the problem then
* notepad Why such an order can be executed on any path, the path environment variable configuration
* C: configuration
* a: xp system
* right-click on the desktop and select properties → → → click the advanced tab select environment variables → Find below the system variables path → Double-click on the path → jdk bin directory under the installation directory to the left and add the semicolon.
* B: win7 / win8 system
* Right-click on the desktop computer → select properties → select Advanced System Settings → select Advanced tab → click Environment Variables → below the system variables find the path → Double-click the path → the bin directory under the jdk installation directory to the left and add the semicolon.
* Path configuration file is an executable .exe, the configuration can be accessed under the path executable file path in a different drive letter
### 01.17_Java language basis (configuration Path environment variable 2)
* A: configure the JAVA_HOME
* B: modify path
* C: Finally, talk about path is a sequential relationship
### 01.18_Java language basis (classpath environment variable and its configuration)
* A: Why do you want to configure classpath
* B: principle classpath configuration
* C: How to configure classpath
* The difference between the path and classpath
* path configuration file is an executable .exe, the configuration can be accessed under the path executable file path in a different drive letter
* classpath configuration of java class file is .class file
### 01.19_Java language basis (Editplus develop programs and compile and run)
* A: Configure the shortcut key to compile and run
* B: remove the backup files
### 01.20_Java language basis (Comment Summary and Classification)
* A: What is a comment
* B: Classification and explain the comment
* documentation comments are currently not speak, said later explain
* Role comment
* A: explanation of procedures
* B: help us debug error
### 01.21_Java language basis (Overview and use of keywords)
* A: What is the keyword
* is given a specific meaning in the Java language word
* B : key features
* consisting of all lowercase letters in keywords
* C: common keyword
* public static void class, etc.
* D: Notes keyword
* goto and const as a reserved word exist, does not currently use, so similar Editplus advanced notepad for keywords have a special color-coded, very intuitive
### 01.22_Java language basis (Overview and composition rules for identifiers)
* A: What is the identifier
* is to give class, sequence of characters from the name used when the interfaces, methods, variables, etc.
* B: consisting of the rules for identifiers
* English uppercase and lowercase letters
* numeric characters
* and $ _
* C: identifier Notes
* 1, can not use the keyword
, you can not start with a number 2 *
### 01.23_Java language based (common naming identifiers)
* See name EENOW
* A: package
* is the best domain name upside down, require that all lowercase
* B: class or interface
* If a word is first capitalized
* If a plurality of words each word is capitalized (hump identification)
* C: a method or a variable
* If a word is all lowercase
* If a plurality of words from the second word capitalized first letter
* D: constant
* If it is a word, all capital letters
* If more than one word, the word all uppercase, with underscores to distinguish each word