如何正确的使用groovy调用外部程序

class StreamConsumer extends Thread{     def instream     def buf     public StreamConsumer(def input){         instream = input         buf = new StringBuffer()     }       public void run(){         def reader = new BufferedReader(new InputStreamReader(instream))         reader.eachLine{ buf.append(it).append('/n')}     } }   class Exec{     static def doCommand(def cmd){         Process proc = Runtime.getRuntime().exec(cmd)         def error = new StreamConsumer(proc.getErrorStream())         def input = new StreamConsumer(proc.geTinputStream())         input.start()         error.start()         proc.waitFor()         input.join()         error.join()         return [             "stdout":input.buf?.toString().trim(),            "stderr":error.buf?.toString().trim(),            ]     } } def cmd = 'dir ' def result = Exec.doCommand(cmd); println result 具体的解释请参考 When Runtime.exec() won't http://www.javaworld.com/javaworld/jw-12-2000/jw-1229-traps.html?page=3