Java编程获取硬盘空间

Java编程获取硬盘空间2010-12-06因为论坛有人问到这个问题，所以就写了这篇文章。希望对大家有所帮助。

一般来讲,要用java得到硬盘空间,有3种方法:

1. 调用system的command,然后分析得到的结果,这种方法有很强的系统依赖性,linux下和win下要分别写程序。

下面是一个win下的例子,编译成功之后,运行java Diskspace yourdir（比如c:）

import java.io.BufferedReader;import java.io.InputStreamReader; /*** Determine free disk space for a given directory by * parsing the output of the dir command.* This class is inspired by the code at* Works only under Windows under certain circumstances.* Yes, it"s that shaky.* Requires Java 1.4 or higher.* @[EMAIL PROTECTED] *Marco Schmidt*/public class Diskspace{ private Diskspace（） {  // prevent instantiation of this class }/*** Return available free disk space for a directory.* @[EMAIL PROTECTED]dirName name of the directory* @[EMAIL PROTECTED]free disk space in bytes or -1 if unknown*/ public static long getFreeDiskSpace（String dirName） {  try  {   // guess correct "dir" command by looking at the    // operating system name   String os = System.getProperty（"os.name"）;   String command;   if （os.equals（"Windows NT"） ||os.equals（"Windows 2000"））   {    command = "cmd.exe /c dir " + dirName;   }   else   {    command = "command.com /c dir " + dirName;   }   // run the dir command on the argument directory name   Runtime runtime = Runtime.getRuntime（）;   Process process = null;   process = runtime.exec（command）;   if （process == null）   {    return -1;   }   // read the output of the dir command   // only the last line is of interest    BufferedReader in = new BufferedReader（new InputStreamReader（process.getInputStream（）））;   String line;   String freeSpace = null;   while （（line = in.readLine（）） ！= null）   {    freeSpace = line;   }   if （freeSpace == null）   {    return -1;   }   process.destroy（）;   // remove dots & commas & leading and trailing whitespace   freeSpace = freeSpace.trim（）;   freeSpace = freeSpace.replaceAll（"\.", ""）;   freeSpace = freeSpace.replaceAll（",", ""）;   String[] items = freeSpace.split（" "）;   // the first valid numeric value in items after（！） index 0   // is probably the free disk space   int index = 1;   while （index < items.length）   {    try    {     long bytes = Long.parseLong（items[index++]）;     return bytes;    }    catch （NumberFormatException nfe）    {    }   }   return -1;  }  catch （Exception exception）  {    return -1;  }  }/*** Command line program to print the free diskspace to stdout* for all 26 potential root directories A: to Z:* （when no parameters are given to this program）* or for those directories （drives） specified as parameters.* @[EMAIL PROTECTED]args program parameters*/ public static void main（String[] args） {  if （args.length == 0）  {   for （char c = "A"; c <= "Z"; c++）   {    String dirName = c + ":\";    System.out.println（dirName + " " +    getFreeDiskSpace（dirName））;   }  }  else  {   for （int i = 0; i < args.length; i++）   {    System.out.println（args[i] + " " + getFreeDiskSpace（args[i]））;   }  } }}