Java Basic JDK environment variable setting and using Notepad for simple Java program development

in http://o racle.com/ , search jdk Download your desired version, personal suggestions download JDK1.7 version is better, because the latest version of the JDK1.8 version is just out, as a beginner, in learning problems may not be convenient to solve (only personal opinion for reference). Click Unzip to install, you can. Http://www.oracle.com/technetwork/java/javase/downloads/index.html



JDK Download website

Open the Bin folder in the JDK, copy the path of the Bin folder, remember that it can not contain Chinese symbols and Chinese characters, because this may affect the environment variable settings, resulting in the computer can not be compiled and run Java programs. Paste the copied path into the new text file.



Right-click Desktop Computer icon-Properties-environment variables-Advanced system settings-environment variables-System variables Click path-Edit-Press the home key on the keyboard to reach the top of the Variable Value text box-paste the Bin folder path you just copied to the front, and the semicolon key under the English input method ";" Separate before and after two address, remember is in English input Method-OK.


Right-click Taskbar-run (shortcut key Win+r)-Enter "cmd"-OK, open DOS command to detect if the environment variables required for Java are set up.


Enter the root directory of the folder where the JDK is installed (example D: Carriage return), enter java-version carriage return, detect if the JDK is installed successfully, and the JDK installation version appears.


input javac-version detects if the JRE is successfully installed, The JRE is installed in the same installer as the JDK, in order to detect whether a Java file can be run. Similarly, the installation version number appears.


Now, we can do simple Java file compilation in Notepad.


In the D drive, right click on the new folder named "Person", and then create a new text file, modify the file name "person", beginning with the English capital letters, cannot appear in Chinese words, the file suffix is changed to ". Java".


Open in Notepad, enter the main frame of the Java Program "public class (file name) {}" carriage return, press the TAB key, enter "public static void Main (string[] args) {}", enter the Java output statement in this curly brace " System.out.println (); ", enter the text characters you want to display in parentheses.




after compiling the text, save and run the file in cmd. Open DOS command, that is, right-click the taskbar-run (shortcut key Win+r)-Enter "cmd"-ok, enter the root directory of the file "D:" carriage return, and then enter "CD person" to the computer released in this root directory for folder lookups.



Enter the Java Person.java command, which, if compiled successfully, produces a Person.class bytecode file in the Person.java file sibling directory.



finally enter "Java person" carriage return, the text character you entered will appear.

The simple use of Notepad to develop the Java program is complete.



Java Basic JDK environment variable setting and using Notepad for simple Java program development