获取一般linux系统的系统信息，java获取单个进程的CPU使用率

引用

一般linux系统内用这些命令获取系统信息：
<info name="cpuCmd" value="top -b -n 1|grep Cpu"></info>
<info name="memCmd" value="top -b -n 1|grep Mem"></info>
<info name="spaceCmd" value="df -h|sed -n '3,$p'"></info><!-- 需要检查系统df命令，是否'3,$p'第三行开始是磁盘信息 -->

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获取单个进程CPU,内存的占用率

cmd脚本命令：top -b -n 1 -p $pid | sed '$d' | sed -n '$p'
上面的$pid，就是进程的PID

/**
	 *  获取当前进程的CPU占有率
	 *  cmd:top -b -n 1 -p $pid | sed '$d' | sed -n '$p' | awk '{print $9}'
	  * @Title: getProcCpu
	  * @Description: TODO
	  * @author:zjz
	  * @create-date:2012-7-16 下午6:22:53
	  * @modify-date:2012-7-16 下午6:22:53
	  * @param @param pid
	  * @param @return    
	  * @return double    
	  * @throws
	*
	 */
public double getProcCpu(int pid){
		Process process=null;
		BufferedReader br = null;
		try {
			if("".equals(procCpuShell))return 0;
			procCpuShell = procCpuShell.replaceAll("\\$pid", pid+"");
			String[] cmd = new String[]{"/bin/sh","-c",procCpuShell};
			process = Runtime.getRuntime().exec(cmd);
			int resultCode = process.waitFor();
			LogCvt.debug("执行结果PID："+pid+"："+resultCode);
			br = new BufferedReader(new InputStreamReader(process.getInputStream()));
			String line = null;
			while((line = br.readLine())!=null ){
				Double cpu = Double.parseDouble(line);
				if(cpu>100)cpu = cpu/10;//刚启动会出现CPU100多情况，则处理除于10
			    return cpu;
			}
		} catch (Exception e) {
			LogCvt.error("执行获取进程CPU使用率错误",e);
		}finally{
			try{
				if(process!=null)process.destroy();
				if(br!=null)br.close();
			}catch(Exception e){
				LogCvt.error(e.getMessage());
			}
			
		}
		return 0.0;
	}

如果要获取单个进程使用的内存可以这样:

        int mb = 1024*1024;    
        // 可使用内存    
        long totalMemory = Runtime.getRuntime().totalMemory() / mb;    
        // 剩余内存    
        long freeMemory = Runtime.getRuntime().freeMemory() / mb;
        // 最大可使用内存    
        long maxMemory =Runtime.getRuntime().maxMemory() / mb;