Question

Recently, when trying to compile java programs from the command prompt, I get this error:

Error: Cannot find or load main class com.sun.tools.javac.Main

I have the latest versions of the JDK and JRE, and I still get the error.
Here is what I type in the command line:

C:\Java_Source_Codes>javac hi.java

Can anyone help?

(Here is my java code)

public class hi{
  public static void main(String[] args){
    System.out.println("hello, world!");
  }
}

Answer 1

You have a number of issues, Kumar mentioned the compilation issue, but that’s not the immediate problem that’s stopping you.

You have JAVA_HOME set to a Java Runtime environment, but are finding javac on the system PATH. When this happens, you can call javac from the command line, but when javac detects the JAVA_HOME environmental variable, it loads its libraries from a directory that doesn’t include the “java tools”, tools.jar. The contents of “java tools” includes the classes that implement the compiler.

You probably have JAVA_HOME set to something like /some/path/here/jre. Assuming that the jre directory is the embedded JRE shipped with your JDK, you probably should have set the JAVA_HOME to /some/path/here.