问题
What can I do when I keep receiving the error
'javac' is not recognized as an internal or external command, operable program or batch file
when I want to compile my jar or .class file?
Thanks
回答1:
Make sure %JAVA_HOME%/bin is on your %PATH% (or $JAVA_HOME on the $PATH in *nix).
回答2:
It means that it is not in your path. You have the following options:
1) Change to the directory where javac lives before calling it.
2) Use the full path to javac when making the call, e.g. C:\java\jdk1.6.0_12\bin\javac ...
3) Add the javac directory to the PATH environment variable
回答3:
This just means that javac isn't in your PATH variable.
On Windows, you just have to add the folder that contains javac.exe to the PATH environment variable (Win+Pause/Break).
On Linux/Mac/Unix, just append that directory to $PATH in .bashrc or similar.
回答4:
The error that you are seeing is generated by Windows, and isn't specific to Java. That error means that you typed a command and Windows could not find the command by that name.
The easiest way of rectifying the situation is to ensure that Java is properly installed in your system's PATH.
First, ensure that you have a JDK installed (and not just a JRE). Your next best bet is to add an environment variable called JAVA_HOME and point it at the base install directory for the version of Java that you installed.
Next, modify your PATH environment variable by prepending the string %JAVA_HOME%\bin; to whatever is already in your PATH. If you look at the contents of that directory, you will see that javac is in there (along with a number of other Java development tools).
回答5:
You have to install JDK (which includes javac compiler) and ensure that it's in the path. See http://java.sun.com/javase/downloads/index.jsp
回答6:
Common Error Messages from SUN Tutorial page
回答7:
Step 4 (Update the PATH variable) of the JDK installation instructions explains what you should do to make it so that you can just type javac in the command prompt window.
回答8:
The link below gives a step by step explanation on how to set up java_home and path variables. JAVA_HOME setup
回答9:
Even if I had
- JDK installed
JAVA_HOMEdefined%JAVA_HOME%\binpresent in my%PATH%
I still had this error. I resolved it by eliminating the JRE from my path variable. It was put before JAVA_HOME, has no javac. It seems Windows can't find javac in JAVA_HOME\bin in this case.
回答10:
For Windows
Control Panel > System...Then click Advanced System Setting (left pane)...then popup window will open...then click Environment Variables...Then another window will open...click New and add enter information below
Variable name: PATH
Variable value: C:\Program Files\Java\jdk1.7.0_45\bin [*make sure this is the right path for you]
Then it should work
回答11:
- Check whether you have JDK installed; if not installed, Install
- If JDK is installed, navigate into the bin folder of the installation, and try to execute javac.
- If javac executes, proceed (+:
- If javac does not execute, check your system path, and java path, and return to 2 above!
来源：https://stackoverflow.com/questions/1299750/javac-not-recognized