unity java_home is not set and no ‘java’ command could be found in your path.

JAVA_HOME is usually means the JDK installation home, such as C:\Java\jdk1. 8.0_131 . It is not the JRE installation home. JRE_HOME is the environment variable which store java runtime environment installation path such as C:\Java\jre8 . CLASSPATH is the path where to find the java class when your application executes.

Short answer, YES, you do need to set JAVA_HOME .

Set JAVA_HOME: Right click My Computer and select Properties. On the Advanced tab, select Environment Variables, and then edit JAVA_HOME to point to where the JDK software is located, for example, C:\Program Files\Java\jdk1 .