Method onPath

src/main/java/net/mtrop/doom/tools/struct/util/OSUtils.java:380–403

Attempts to detect if an executable is present on the platform's PATH by name. On Windows, this is done through the where command. On Unix-like systems, the which command. @param imageName the executable name. @return true if so, false if not. @throws NullPointerException i

(String imageName)

	 * @throws UnsupportedOperationException if a mechanism to search the PATH environment does not exist.
	 */
	public static boolean onPath(String imageName)
	{
		Objects.requireNonNull(imageName);
		
		try {
			ProcessBuilder pb = (new ProcessBuilder())
				.redirectInput(Redirect.from(NULL_FILE))
				.redirectError(Redirect.appendTo(NULL_FILE))
				.redirectOutput(Redirect.appendTo(NULL_FILE))
			;
			if (IS_WINDOWS)
				pb.command("where", imageName);
			else if (IS_OSX || IS_LINUX)
				pb.command("which", imageName);
			else
				throw new UnsupportedOperationException("OS does not have \"where\" or \"which\" available for PATH search!");
			int status = pb.start().waitFor();
			return status == 0;
		} catch (IOException e) {
			throw new UnsupportedOperationException("OS does not have \"where\" or \"which\" available for PATH search!");
		} catch (InterruptedException e) {
			return false; // Shouldn't happen.
		}
	}
	
}