android项目得到进程数量，运行内存和剩余运行内存

package com.itheima.utils;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStreamReader;

import android.app.ActivityManager;
import android.app.ActivityManager.MemoryInfo;
import android.content.Context;
import android.text.format.Formatter;

public class RunRomUtils {
    //得到运行的程序
    public static int getCountRom(Context context){
        ActivityManager am = (ActivityManager) context.getSystemService(context.ACTIVITY_SERVICE);
        return am.getRunningAppProcesses().size();
        
    }
    //得到剩余运行内存空间
    public static String getAvail(Context context){
        ActivityManager am = (ActivityManager) context.getSystemService(context.ACTIVITY_SERVICE);
        MemoryInfo outInfo = new MemoryInfo();
        am.getMemoryInfo(outInfo );
        
        return Formatter.formatFileSize(context, outInfo.availMem);
    }
    //得到总运行内存空间
    public static String getTotal(Context context){
        //4.1.2及以上可以用这个办法
//        ActivityManager am = (ActivityManager) context.getSystemService(context.ACTIVITY_SERVICE);
//        MemoryInfo outInfo = new MemoryInfo();
//        am.getMemoryInfo(outInfo );
//        return Formatter.formatFileSize(context, outInfo.totalMem);
        File file = new File("/proc/meminfo");
        FileInputStream fileIn;
        try {
            fileIn = new FileInputStream(file);
            InputStreamReader in = new InputStreamReader(fileIn);
            BufferedReader br = new BufferedReader(in);
            String result = br.readLine();
            String total = "";
            StringBuffer sb = new StringBuffer();
            for (char c : result.toCharArray()) {
                if(c>='0'&&c<='9'){
                    sb.append(c);
                }
            }
            int c = Integer.valueOf(sb.toString())*1024;
            return Formatter.formatFileSize(context,c);
            
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return "";
        }
    }
}