Разве я не посылаю массив команд "Hello World", чтобыExec () правильно?

правильный вывод, привет мир:

thufir@mordor:~$ 
thufir@mordor:~$ java -jar NetBeansProjects/HelloExec/dist/HelloExec.jar 
Apr 05, 2016 7:11:23 AM net.bounceme.mordor.telnet.Main run
INFO: starting..
Apr 05, 2016 7:11:23 AM net.bounceme.mordor.telnet.Telnet <init>
INFO: connecting..
Apr 05, 2016 7:11:23 AM net.bounceme.mordor.telnet.Telnet connect
INFO: connect..
Apr 05, 2016 7:11:23 AM net.bounceme.mordor.telnet.Telnet connect
INFO: [echo hello 1, echo hello 2, echo hello 3]
Apr 05, 2016 7:11:24 AM net.bounceme.mordor.telnet.Telnet connect
INFO: did process..
Apr 05, 2016 7:11:24 AM net.bounceme.mordor.telnet.Telnet connect
INFO: trying..
hello 1
Apr 05, 2016 7:11:24 AM net.bounceme.mordor.telnet.Telnet read
SEVERE: exiting.. 0
thufir@mordor:~$ 

код:

package net.bounceme.mordor.telnet;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
import java.util.logging.Level;
import java.util.logging.Logger;
import static java.lang.System.out;

public class Telnet {

    private final static Logger LOG = Logger.getLogger(Telnet.class.getName());

    public Telnet() {
        LOG.info("connecting..");
    }

    private List<String> getCommand() {
        List<String> commands = new ArrayList<>();
        commands.add("echo hello 1");
        commands.add("echo hello 2");
        commands.add("echo hello 3");
        return commands;
    }

    private void read(Process process) throws IOException, InterruptedException {
        BufferedReader input = new BufferedReader(new InputStreamReader(process.getInputStream()));
        String line = null;
        while ((line = input.readLine()) != null) {
            out.println(line);
        }
        int exitVal = process.waitFor();
        LOG.log(Level.SEVERE, "exiting.. {0}", exitVal);
    }

    private void connect() {
        LOG.info("connect..");
        Runtime runtime = Runtime.getRuntime();
        List<String> cmds = getCommand();
        String[] cmdArray = cmds.toArray(new String[cmds.size()]);
        String command = cmdArray[0];
        LOG.info(cmds.toString());
        Process process = null;
        try {
            process = runtime.exec(command);
        } catch (IOException ex) {
            LOG.severe("process wrong");
            Logger.getLogger(Telnet.class.getName()).log(Level.SEVERE, null, ex);
        }
        LOG.info("did process..");

        LOG.info("trying..");
        try {
            read(process);
        } catch (IOException | InterruptedException ex) {
            LOG.severe("read wrong");
            Logger.getLogger(Telnet.class.getName()).log(Level.SEVERE, null, ex);
        }

    }

    public void tryConnect() {
        connect();
    }
}

авария:

thufir@mordor:~$ 
thufir@mordor:~$ java -jar NetBeansProjects/HelloExec/dist/HelloExec.jar 
Apr 05, 2016 7:12:32 AM net.bounceme.mordor.telnet.Main run
INFO: starting..
Apr 05, 2016 7:12:32 AM net.bounceme.mordor.telnet.Telnet <init>
INFO: connecting..
Apr 05, 2016 7:12:32 AM net.bounceme.mordor.telnet.Telnet connect
INFO: connect..
Apr 05, 2016 7:12:32 AM net.bounceme.mordor.telnet.Telnet connect
INFO: [echo hello 1, echo hello 2, echo hello 3]
Apr 05, 2016 7:12:32 AM net.bounceme.mordor.telnet.Telnet connect
SEVERE: process wrong
Apr 05, 2016 7:12:32 AM net.bounceme.mordor.telnet.Telnet connect
SEVERE: null
java.io.IOException: Cannot run program "echo hello 1": error=2, No such file or directory
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)
    at java.lang.Runtime.exec(Runtime.java:620)
    at java.lang.Runtime.exec(Runtime.java:485)
    at net.bounceme.mordor.telnet.Telnet.connect(Telnet.java:48)
    at net.bounceme.mordor.telnet.Telnet.tryConnect(Telnet.java:66)
    at net.bounceme.mordor.telnet.Main.run(Main.java:17)
    at net.bounceme.mordor.telnet.Main.main(Main.java:11)
Caused by: java.io.IOException: error=2, No such file or directory
    at java.lang.UNIXProcess.forkAndExec(Native Method)
    at java.lang.UNIXProcess.<init>(UNIXProcess.java:248)
    at java.lang.ProcessImpl.start(ProcessImpl.java:134)
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029)
    ... 6 more

Apr 05, 2016 7:12:32 AM net.bounceme.mordor.telnet.Telnet connect
INFO: did process..
Apr 05, 2016 7:12:32 AM net.bounceme.mordor.telnet.Telnet connect
INFO: trying..
Exception in thread "main" java.lang.NullPointerException
    at net.bounceme.mordor.telnet.Telnet.read(Telnet.java:30)
    at net.bounceme.mordor.telnet.Telnet.connect(Telnet.java:57)
    at net.bounceme.mordor.telnet.Telnet.tryConnect(Telnet.java:66)
    at net.bounceme.mordor.telnet.Main.run(Main.java:17)
    at net.bounceme.mordor.telnet.Main.main(Main.java:11)
thufir@mordor:~$ 

при попытке использоватьcmdArray:

process = runtime.exec(cmdArray);

Рассуждение:

... это потому, что когда exec дается одна строка, она сначала анализирует ее (так, как нам не нравится). Напротив, когда exec передается строковый массив, он просто передает его операционной системе, не анализируя его.

https://stackoverflow.com/a/19383655/262852