无法使用processBuilder执行linux命令

Question

I using Processbuilder as follows:

            List<String> args = initArgs();
            ProcessBuilder pb = new ProcessBuilder(args);
            tdmServerProcess = pb.start();

            handleInfoLog(tdmServerProcess.getInputStream());
            handleErrorLog(tdmServerProcess.getErrorStream());

In the initArgs method I am setting the linux commands I want to execute, as follows:

args.add("java -version");
args.add(javaHome + File.separator + "bin" + File.separator + "java");

first command is getting executed successfully. But second is failing with following error:

/opt/java7/bin/java: cannot execute binary file

though i have execute permission, following are permission bits:

-r-xr-xr-x 

I am able to execute the same command from terminal.

Answer 1

The error "cannot execute binary file" means that the java file is not valid. Maybe the 'java -version' is actually running java from another location in your path, and the /opt/java7/bin/java is not valid. Try running the '/opt/java7/bin/java' manually, and check the result. Check also the location of java in your path by running which java using the same user that your are running your java code with.

Answer 2

You apparently are trying to execute two separate commands, first "java -version" and then "/opt/java7/bin/java" ?

That's not how it works. Rather, all of the arguments are appended and one process is started. In your case, the command is "java -version /opt/java7/bin/java"

Try running that at the console - I'm betting that you get the same error.