import java.io.BufferedReader;  import java.io.FileInputStream;  import java.io.IOException;  import java.io.InputStreamReader;  import java.util.ArrayList;  import java.util.HashMap;  import java.util.List;  import java.util.Map;  import java.util.StringTokenizer;    import org.apache.commons.io.FileSystemUtils;    public class OSUtils {        /**       * 功能：可用磁盘       * */      public static int disk() {          try {              long total = FileSystemUtils.freeSpaceKb("/home");              double disk = (double) total / 1024 / 1024;              return (int) disk;          } catch (IOException e) {              e.printStackTrace();          }          return 0;      }        /**       * 功能：获取Linux系统cpu使用率       * */      public static int cpuUsage() {          try {              Map<?, ?> map1 = OSUtils.cpuinfo();              Thread.sleep(5 * 1000);              Map<?, ?> map2 = OSUtils.cpuinfo();                long user1 = Long.parseLong(map1.get("user").toString());              long nice1 = Long.parseLong(map1.get("nice").toString());              long system1 = Long.parseLong(map1.get("system").toString());              long idle1 = Long.parseLong(map1.get("idle").toString());                long user2 = Long.parseLong(map2.get("user").toString());              long nice2 = Long.parseLong(map2.get("nice").toString());              long system2 = Long.parseLong(map2.get("system").toString());              long idle2 = Long.parseLong(map2.get("idle").toString());                long total1 = user1 + system1 + nice1;              long total2 = user2 + system2 + nice2;              float total = total2 - total1;                long totalIdle1 = user1 + nice1 + system1 + idle1;              long totalIdle2 = user2 + nice2 + system2 + idle2;              float totalidle = totalIdle2 - totalIdle1;                float cpusage = (total / totalidle) * 100;              return (int) cpusage;          } catch (InterruptedException e) {              e.printStackTrace();          }          return 0;      }        /**       * 功能：CPU使用信息       * */      public static Map<?, ?> cpuinfo() {          InputStreamReader inputs = null;          BufferedReader buffer = null;          Map<String, Object> map = new HashMap<String, Object>();          try {              inputs = new InputStreamReader(new FileInputStream("/proc/stat"));              buffer = new BufferedReader(inputs);              String line = "";              while (true) {                  line = buffer.readLine();                  if (line == null) {                      break;                  }                  if (line.startsWith("cpu")) {                      StringTokenizer tokenizer = new StringTokenizer(line);                      List<String> temp = new ArrayList<String>();                      while (tokenizer.hasMoreElements()) {                          String value = tokenizer.nextToken();                          temp.add(value);                      }                      map.put("user", temp.get(1));                      map.put("nice", temp.get(2));                      map.put("system", temp.get(3));                      map.put("idle", temp.get(4));                      map.put("iowait", temp.get(5));                      map.put("irq", temp.get(6));                      map.put("softirq", temp.get(7));                      map.put("stealstolen", temp.get(8));                      break;                  }              }          } catch (Exception e) {              e.printStackTrace();          } finally {              try {                  buffer.close();                  inputs.close();              } catch (Exception e2) {                  e2.printStackTrace();              }          }          return map;      }        /**       * 功能：内存使用率       * */      public static int memoryUsage() {          Map<String, Object> map = new HashMap<String, Object>();          InputStreamReader inputs = null;          BufferedReader buffer = null;          try {              inputs = new InputStreamReader(new FileInputStream("/proc/meminfo"));              buffer = new BufferedReader(inputs);              String line = "";              while (true) {                  line = buffer.readLine();                  if (line == null)                      break;                  int beginIndex = 0;                  int endIndex = line.indexOf(":");                  if (endIndex != -1) {                      String key = line.substring(beginIndex, endIndex);                      beginIndex = endIndex + 1;                      endIndex = line.length();                      String memory = line.substring(beginIndex, endIndex);                      String value = memory.replace("kB", "").trim();                      map.put(key, value);                  }              }                long memTotal = Long.parseLong(map.get("MemTotal").toString());              long memFree = Long.parseLong(map.get("MemFree").toString());              long memused = memTotal - memFree;              long buffers = Long.parseLong(map.get("Buffers").toString());              long cached = Long.parseLong(map.get("Cached").toString());                double usage = (double) (memused - buffers - cached) / memTotal * 100;              return (int) usage;          } catch (Exception e) {              e.printStackTrace();          } finally {              try {                  buffer.close();                  inputs.close();              } catch (Exception e2) {                  e2.printStackTrace();              }          }          return 0;      }  }