run.exec的使用问题

大家好。本人现在要用到run.exec程序。代码如下[code="java"]
String commond = "mxmlc "+writer;

Runtime run = Runtime.getRuntime();

try {

String[] cmd = new String[4];

cmd[0] = "cmd";

cmd[1] = "c:";

cmd[2] = "cd Program Files/Adobe/Flex Builder 3 Plug-in/sdks/3.2.0/bin ";

cmd[3]=commond;
Process p = run.exec(cmd[0]);

int existValue= p.waitFor();
System.out.println(existValue);

            //download。。。。。

[/code]
writer是文件的绝对路径。我的意图是编译文件后生成swf文件后下载。但是现在不知道怎么回事总是卡在p.waitFor();中。我本来是要打算用这个来控制文件生成后在下载的，要不然总报找不到文件异常。但是不知道这个用法能不能控制。再者怎么调试run.exec命令啊。我现在根本不知道命令执行没执行。执行到哪了，反正是没成功。有这方面经验的朋友麻烦帮解答下。谢谢

给你一个之前写的方法：
code="java"]/**
* PDF轉換為SWF
* @param sourcePath 源文件路径
* @param destPath 目标文件路径
* @param fileName
* @return
* @throws IOException
*/
public static synchronized int convertPDF2SWF(String projctPath, String sourcePath, String destPath, String fileName) throws IOException {
File dest = new File(destPath);
if(!dest.exists())
dest.mkdirs();

File source = new File(sourcePath);
if(!source.exists())
return 0;
String command = "";
//判斷當前的操作系統以調用不同的命令
String osType = System.getProperty("os.name");
if(osType.toLowerCase().indexOf("windows") != -1)
command = projctPath+File.separator+"software"+File.separator+"SWFTools"+File.separator+"pdf2swf -o "+destPath+fileName+" -z -B "+projctPath+File.separator+"software"+File.separator+"SWFTools"+File.separator+"rfxview.swf -s flashversion=9 -s -t "+sourcePath+" -s languagedir="+projctPath+File.separator+"software"+File.separator+"xpdf-chinese-simplified";
else
command = "/usr/local/bin/pdf2swf -o " + destPath + fileName + " -z -B /usr/local/share/swftools/swfs/rfxview.swf -s flashversion=7 -t " + sourcePath;
Process process = Runtime.getRuntime().exec(command);
BufferedReader br = new BufferedReader(new InputStreamReader(process.getInputStream()));
while(br.readLine() != null);
try {
process.waitFor();
} catch (InterruptedException e) {
e.printStackTrace();
}
return process.exitValue();
}[[/code]