Why can 1,java run across platforms? Please outline the principle.
Since the code compiled by the Java program is not code that can be run directly by the hardware system, it is an "intermediate code"-bytecode. A different Java Virtual machine (JVM) is then installed on different hardware platforms, which are then "translated" by the JVM into code that the corresponding hardware platform can execute. So for Java programmers, there is no need to consider what the hardware platform is. So Java can be cross-platform.
If you are porting to UNIX with Windows, simply translate the Java file into a class file that is the UNIX JVM creates Macintosh and then run it with the JVM.
2, try installing and configuring the JDK, and give the steps to install and configure the JDK.
1. Open My Computer--Properties--advanced--environment variables
2. New system Variable Java_home
Variable name: java_home
Variable value: The directory of the JDK, such as D:/java
3. Select the environment variable named "Path" in "System variables"
Double-click the variable to add the absolute path of the bin directory in the JDK installation path to the value of the path variable, separating it with the semicolon of the half-width and the existing path.
Variable name: Path
Added variable value:%java_home%\bin;%java_home%\jre\bin;
3. What is the role of the environment variable path and java_home when configuring the JDK?
This is the Java environment configuration, the configuration is completed directly after the eclipse, it will automatically complete the configuration of the Java environment
Java Basics Quiz