CLASS - Java Class File

What is a CLASS file

Java compilers can create compiled JAVA files that have the CLASS file extension. These files can be executed using a Java Virtual Machine (JVM). Likewise, the Java Runtime Environment (JRE) can execute CLASS files, however it is unable to compile them. CLASS files are generally compatible with the JVM version they have been created in. A CLASS file that has been created using a different JVM may not be compatible with other JVM versions.

The CLASS file contains bytecode in its binary form. Running the JVM, these files and the code contained in them can be executed. Most commonly, CLASS files are bundled and compressed in JAR files. To compile a CLASS file from a JAVA file, the javac-command of the JVM has to be used. This can easily be done on the fly by using a Java IDE like Eclipse.

Here's a small, but not exhaustive list of programs that can open CLASS documents:

  • Apple Jar Launcher (Mac)
  • dirtyJOE (Windows)
  • DJ Java Decompiler (Windows)
  • Eclipse IDE for Java Developers (Windows, Mac & Linux)
  • JD-GUI (Windows, Mac & Linux)
  • Oracle Java Runtime Environment (Windows, Mac & Linux)
Extension CLASS
MIME type application/java, application/java-vm, application/java-byte-code, application/x-java-class, application/x-java-vm, application/x-java-bean, application/x-jinit-bean, application/x-jinit-applet
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