* 取得linux系统下的cpu、内存信息
*
* */
public  final  class LinuxSystemTool
{
/**
* get memory by used info
*
* @return int[] result
* result.length==4;int[0]=MemTotal;int[1]=MemFree;int[2]=SwapTotal;int[3]=SwapFree;
* @throws IOException
* @throws InterruptedException
*/
public  static  int [] getMemInfo() throws IOException, InterruptedException
{
File file = new File( "/proc/meminfo" );
BufferedReader br = new BufferedReader( new InputStreamReader(
new FileInputStream(file)));
int [] result = new  int [ 4 ];
String str = null ;
StringTokenizer token = null ;
while ((str = br.readLine()) != null )
{
token = new StringTokenizer(str);
if (!token.hasMoreTokens())
continue ;  str = token.nextToken();
if (!token.hasMoreTokens())
continue ;  if (str.equalsIgnoreCase( "MemTotal:" ))
result[0 ] = Integer.parseInt(token.nextToken());
else  if (str.equalsIgnoreCase( "MemFree:" ))
result[1 ] = Integer.parseInt(token.nextToken());
else  if (str.equalsIgnoreCase( "SwapTotal:" ))
result[2 ] = Integer.parseInt(token.nextToken());
else  if (str.equalsIgnoreCase( "SwapFree:" ))
result[3 ] = Integer.parseInt(token.nextToken());
}  return result;
}  /**
* get memory by used info
*
* @return float efficiency
* @throws IOException
* @throws InterruptedException
*/
public  static  float getCpuInfo() throws IOException, InterruptedException
{
File file = new File( "/proc/stat" );
BufferedReader br = new BufferedReader( new InputStreamReader(
new FileInputStream(file)));
StringTokenizer token = new StringTokenizer(br.readLine());
token.nextToken();
int user1 = Integer.parseInt(token.nextToken());
int nice1 = Integer.parseInt(token.nextToken());
int sys1 = Integer.parseInt(token.nextToken());
int idle1 = Integer.parseInt(token.nextToken());  Thread.sleep(1000 );  br = new BufferedReader(
new InputStreamReader( new FileInputStream(file)));
token = new StringTokenizer(br.readLine());
token.nextToken();
int user2 = Integer.parseInt(token.nextToken());
int nice2 = Integer.parseInt(token.nextToken());
int sys2 = Integer.parseInt(token.nextToken());
int idle2 = Integer.parseInt(token.nextToken());  return ( float )((user2 + sys2 + nice2) - (user1 + sys1 + nice1)) / ( float )((user2 + nice2 + sys2 + idle2) - (user1 + nice1 + sys1 + idle1));
}
}  

$ cat /proc/meminfo total: used: free: shared: buffers: cached:
Mem: 1057009664 851668992 205340672 0 67616768 367820800
Swap: 2146787328 164429824 1982357504
MemTotal: 1032236 kB
MemFree: 200528 kB
MemShared: 0 kB 

CREATE  TABLE `warnlist` (

 `Id` bigint (20) NOT  NULL auto_increment,

 `warnleave` tinyint(2) NOT  NULL  default  '0' ,//告警级别：告警的严重程度

 `fromguy` varchar (20) NOT  NULL ,//属于哪个用户哪个组织的告警

 `warncontent` varchar (100) NOT  NULL ,//告警内容，比如cpu使用率超过80%

 `aviliablevalue` varchar (12) default  NULL ,//允许值 比如85%

 `warnvalue` varchar (12) default  NULL ,//告警值 80

 `warntime` datetime NOT  NULL ,//告警时间

 `stackinfo` varchar (255) default  NULL ,//异常的堆栈信息

 `dealwith` tinyint(2) NOT  NULL  default  '0' ,//处理结果

 `version` int (11) default  NULL ,//version

 `organizerID` varchar (20) default  NULL ,//组织id

 `des` varchar (255) default  NULL ,

 PRIMARY  KEY  (`Id`)

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

假设我ajax从系统取信息后，那么要写个逻辑，if(cpuTempature>75C)or if(cpuUserd>80%)则写入数据库，然后再查询大于上一次发送Ajax数据库的最大id的告警信息（这期间如果发生的以下错误一并查 出：用户存储空间不足，还有我们公司的业务操作失败告警，Exception等），循环插入一个xml解析类中，大概形式是这样的Ajax返回这个 xml,供页面提取信息