Java environment variable settings

Author: scruffybear Release time: 13/10/2006 Company: watchdata If any reprint is found, indicate the source and maintainArticleIntegrity. Thank you! The Java environment has been configured many times. Every configuration goes online to find the configuration method, which is now recorded to avoid repeated efforts. Configuration of JDK environment variables: JDK version: jdk1.6.0 First install JDK in C. After installation, the directory is: C:/program files/Java/jdk1.6.0. Right-click my computer and select Advanced ---> environment variable. The configuration is as follows: Java_home = C:/program files/Java/jdk1.6.0; Path = % java_home %/bin; Classpath =.; % java_home %/lib/dt. jar; % java_home %/lib/tool. jar; Click OK. Helloworld. Java classic testCode: Public class helloworld { Public static void main (string ARGs []) { System. Out. println ("Hello world! ") } } Command Line input: javac helloworld. Java Generate helloworld. Class Command Line input: Java helloworld Print "Hello World!" on the screen! " Set java_home, classpath, and path as follows: 1. Set java_home: 1. For reference convenience, for example, if your JDK is installed in the C:/program files/Java/jdk1.6.0 directory, set java_home to the directory path, to use this path in the future, you only need to enter % java_home % to avoid entering a long path string for each reference; Ii. Normalization principle: when your JDK path is forced to change, you only need to change the variable value of java_home. Otherwise, you need to change any document that uses the absolute path to reference the JDK directory, if you haven't completed the changeProgramIf JDK is not found, the system crashes! 3. The third-party software will reference the agreed java_home variable. Otherwise, you will not be able to use the software normally. After using Java for a long time, you will know that if a software cannot be used normally, think about the problem. 2. Set classpath: This is a very interesting question. Of course, it is also a question that affects beginners. The purpose of this variable setting is to allow the program to find the corresponding ". for example, compile a Java program ---. java,. class class file. If you execute Java A in the current directory, the corresponding result will be obtained (provided that you have set classpath ". "). now. when the class is moved to another directory (for example, "E:/") and Java A is executed, there will be a noclassdeffinderror exception because it cannot be found. class file, now you add classpath :".; e:/"run Java A again to see what the result will be ~~ :)~~~, Everything is normal. The Java Command finds the. Class file through classpath! 3. Set path: The principle is very simple. Do you want to use % java_home %/bin/Java to execute Java commands at any time? Of course not, so, you can add % java_home %/bin to the path. In this way, we can use Java to execute commands in any path. (When you enter your code in the Command Prompt window, the operating system will find the corresponding application in the current directory and PATH variable directory and execute it .) In addition, jcreator4.0 is installed, which is easy to use and has a syntax prompt function. I thought it wasn't. Remember that jcreator2.5 was installed after jcreator2.5, and jcreator2.5 needs to be set before it can be used, in configure-> Option-> Workspace-> Class View, select the prompt option on the right, click OK, and enter ". ", the class method is prompted in the drop-down box, hooray!