Here you can find the source of exec(String... cmdarray)
public static String exec(String... cmdarray)
//package com.java2s; /*// w w w . j a va 2 s . c o m * Utilities.java * * Copyright (C) 1998-2005 Peter Graves * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ import java.io.BufferedReader; import java.io.InputStreamReader; public class Main { public static String exec(String... cmdarray) { try { Process process = Runtime.getRuntime().exec(cmdarray); BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream())); StringBuilder sb = new StringBuilder(); String s; while ((s = reader.readLine()) != null) { if (s.length() > 0) { if (sb.length() > 0) sb.append('\n'); sb.append(s); } } process.getInputStream().close(); process.getOutputStream().close(); process.getErrorStream().close(); process.waitFor(); return sb.toString(); } catch (Throwable t) { return null; } } }