It means that javac.exe executable file, which exists in bin directory of JDK installation folder is not added to PATH environment variable . You need to add JAVA_HOME/bin folder in your machine’s PATH to solve this error. You cannot compile and run Java program until your add Java into your system’s PATH variable.
Read moreCan I run Java on a Mac?
Java 7 and later versions can run on your Mac . Oracle Java (Version 7 and later versions) requires an Intel-based Mac running Mac OS X 10.7. 3 (Lion) or later and administrator privileges for installation.
Read moreHow do I run a Java file in Terminal?
How to run a java program
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