JDK installed but no javap?

Question

I have the JDK 10.0.2 installed, have the cmd opened in the folder of the class files of my program and try the command: javap Simulation.class . I get the error that the command javap is not found. What do I do wrong?

Answer 1

You must have your $JAVA_HOME/bin directory added to system PATH for javap command to be available without it's absolute path.

Alternatively you can call javap using the absolute path:

/usr/lib/.../bin/javap Simulation.class

Answer 2

append $JAVA_HOME/bin to system $PATH variable. for example on linux

JAVA_HOME= "path of java installation on system"

export PATH = $JAVA_HOME/bin:$PATH

Answer 3

Assuming you are on Windows, check in your environment variable PATH whether path to Java executables is set. Ex. If you have installed Java on path,say, C:\Program Files\Java\jdk-10 Then you have to add C:\Program Files\Java\jdk-10\bin to your PATH environment variable to be able to execute java commands from anywhere on command line.

References for Oracle Docs

• https://docs.oracle.com/javase/10/install/installation-jdk-and-jre-microsoft-windows-platforms.htm#JSJIG-GUID-DAF345BA-B3E7-4CF2-B87A-B6662D691840
• https://www.java.com/en/download/help/path.xml

On a sidenote, recommend you to move to Java 11 or 17 now that Java 10 is no longer supported. The above instructions would still remain same.

Answer 4

1. Open the control panel and type envir in search bar.

2. Click on edit the system environment variables.

3. Click on environment variables in the advanced system properties.

4. Click on path mentioned in user variables.

5. Edit the path, and click new and paste the path of java jdk.

6. In my system, the path is C:\Program Files\Java\jdk-17.0.2\bin, it could be different for your system.

7. Click ok, the problem must be solved now.