下面，我以修改某一文件的权限为777为例：

/** 执行Linux命令，并返回执行结果。 */
public static String exec(String[] args) {
String result = "";
ProcessBuilder processBuilder = new ProcessBuilder(args);
Process process = null;
InputStream errIs = null;
InputStream inIs = null;
try {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
int read = -1;
process = processBuilder.start();
errIs = process.getErrorStream();
while ((read = errIs.read()) != -1) {
baos.write(read);
}
baos.write('\n');
inIs = process.getInputStream();
while ((read = inIs.read()) != -1) {
baos.write(read);
}
byte[] data = baos.toByteArray();
result = new String(data);
} catch (IOException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (errIs != null) {
errIs.close();
}
if (inIs != null) {
inIs.close();
}
} catch (IOException e) {
e.printStackTrace();
}
if (process != null) {
process.destroy();
}
}
return result;
}

下面在我们需要的地方调用上面函数即可：

String[] args = { "chmod", "777", "(文件路径)"};
exec(args);