Program can't be found in PATH by Java Runtime on Mac OS X

问题

I am using ImageMagick on Mac OS X (10.7). I installed it with the help of MacPorts.

When I now enter the Terminal and write:

identify image.jpg

it is working perfectly fine.

But now while executing it from within Java, the following exception gets thrown:

org.im4java.core.CommandException: java.io.FileNotFoundException: identify

I can see it's on the PATH by running:

which identify

with the response:

/opt/local/bin/identify

Now while running:

echo $PATH

I get the response:

/opt/local/bin:/opt/local/sbin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin

The same code works perfectly on Windows where ImageMagick is also installed.

So why is im4java not finding identify in the PATH at all?

回答1:

Try setting the search path to the target directory:

import org.im4java.process.ProcessStarter;
ProcessStarter.setGlobalSearchPath("/opt/local/bin");

回答2:

Like it's described here for OS X 10.8 and here for OS X 10.7 the only complete solution is to set your PATH in /etc/launchd.conf.

Per default the PATH for Applications ist set to /usr/bin:/bin:/usr/sbin:/sbin, even if you do not have a /etc/launchd.conf at all.

So you have to do the following in your terminal:

sudo vi /etc/launchd.conf

and add the following line or modify it, if it already exists:

setenv PATH /opt/local/bin:/opt/local/sbin:/usr/bin:/bin:/usr/sbin:/sbin

Important: Now you need to reboot your Mac!

You can reproduce your PATH in your Java application with the following code:

public class Main {
    public static void main (String[] args) {
        System.out.println("PATH=" + System.getenv().get("PATH"));
    }
}

There is a second solution, if you start your Program from within an IDE like Eclipse you can set the PATH there as well. In Eclipse you can do that via Run | Run Configurations | Environment while selecting your launch configuration on the left side bar under Java Application.

I did reproduce it with the following code and image.jpg located in ${user.dir} aka the current directory where your Java app got launched from.

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

public class Main {
    public static void main (String[] args) {
        System.out.println("PATH=" + System.getenv().get("PATH"));
        try {
            Process exec = Runtime.getRuntime().exec("identify image.jpg");
            InputStream is = exec.getInputStream();
            InputStreamReader isr = new InputStreamReader(is);
            BufferedReader br = new BufferedReader(isr);
            System.out.println(br.readLine());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

You should get similar output like this after running the code above:

PATH=/opt/local/bin:/opt/local/sbin:/usr/bin:/bin:/usr/sbin:/sbin
image.jpg JPEG 690x518 690x518+0+0 8-bit sRGB 152KB 0.000u 0:00.000

The first output line show your PATH for the Java application you run right now. The second output line comes from identify image.jpg.

Note: I am running Mac OS X 10.8.2 and MacPorts 2.1.3

Note: There were a way prior to Mac OS X 10.8 to set global variables on a user by user base employing ~/.MacOSX/environment.plist. But this is no longer working anymore starting with Mountain Lion (aka Mac OS X 10.8). Details can be checked out here:

https://apple.stackexchange.com/questions/57385/where-are-system-environment-variables-set-in-mountain-lion

回答3:

I assume the Java program is not started from the shell, or as another user (in the latter case, my answer will not help). The same is true for MacOS 10.8, this method does not work there, as Uwe pointed out (see comments for details).

When a program is started from somewhere else than the shell, the environment variables set in the shell configuration scripts like profile or bashrc are obviously not available. To set environment variables for those applications, use the file .MacOSX/environment.plist in your home directory. To create the file, you will need to use the shell, then open it with the property list editor that comes with Xcode and set the PATH variable to the value needed. For details have a look at the documentation from Apple: Mac Developer Library: User Session Environment Variables

Here is an example of the content of an environment.plist file:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
    <dict>
        <key>LSCOLORS</key>
        <string>gxfxcxdxbxegedabagacad</string>
        <key>PATH</key>
        <string>/usr/local/bin:/usr/local/sbin:/usr/X11/bin:/usr/local/share/python</string>
   </dict>
</plist>

来源：https://stackoverflow.com/questions/15115971/program-cant-be-found-in-path-by-java-runtime-on-mac-os-x

标签

java

macos

path

ImageMagick

identify