检查您是否已定义环境变量 JAVA_HOME 并将其设置为 JDK 的根目录(不仅仅是 JRE，它不包括 javac)>

I got the error "IOException: Cannot run program "javac": CreateProcess error=2, The system cannot find the file specified" while running my scala project in play 2. why does this error occur . Please solve this problem.

Check that you have the environment variable JAVA_HOME defined and set to the root directory of your JDK (not just a JRE, which doesn't include javac)