java中執行多條shell命令，除了第一條其他都未執行__java

最近項目中需要在在java中執行shell命令，用了最常見方式，代碼如下:

public class ShellUtil {    public static String runShell(String shStr) throws Exception {        Process process;        process = Runtime.getRuntime().exec(new String[]{"/bin/sh","-c",shStr});        process.waitFor();        BufferedReader read = new BufferedReader(new InputStreamReader(process.getInputStream()));        String line = null;        String result = "";        while ((line = read.readLine())!=null){            result+=line;        }        return result;    }}

在調用時如下調用：

public class ExecuteShell {    public static void main (String[] args){        String command = "some command";        String message = ShellUtil.runShell(command);        System.out.println(message);    }}

如果你要同時執行兩個命令或者多個命令的情況下，那麼調用就會如下所示：

public class ExecuteShell {    public static void main (String[] args){        String command1 = "some command";        String command2 = "some command";        String message1 = ShellUtil.runShell(command1);        String message2 = ShellUtil.runShell(command2);        System.out.println(message1);        System.out.println(message2);    }}

當時為了節約效能，改為如下形式：

public class ExecuteShell {    public static void main (String[] args){        String command1 = "some command";        String command2 = "some command";        String command = command1 + " && " + command2;        String message = ShellUtil.runShell(command);        System.out.println(message);    }}

本以為會取巧一下，但是實際結果為，都不會執行了，即整個返回為空白，第一條和第二條都沒有執行。 解決方案

google了一下：http://stackoverflow.com/questions/21908645/command-in-runtime-getruntime-exec-not-working

按照上述的方案將代碼改為

public class ShellUtil {    private static Logger logger = LoggerFactory.getLogger(ShellUtil.class);    public static String runShell(String shStr) throws Exception {        Process process;        process = Runtime.getRuntime().exec(new String[]{"/bin/sh","-c",shStr});        process.waitFor();        BufferedReader read = new BufferedReader(new InputStreamReader(process.getInputStream()));        String line = null;        String result = "";        while ((line = read.readLine())!=null){            result+=line;        }        return result;    }}

即將Runtime.getRuntime().exec("command"); 改為 Runtime.getRuntime().exec(new String[]{"/bin/sh","-c","command"});

注意：如果是windows作業系統要改為Runtime.getRuntime().exec(new String[]{"**cmd** exe","-c","command"});

至此，問題解決。

原理解析：（待補充- -）