关于android:Android设备唯一性判断

package com.suning.mobile.epa;
 
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
 
import android.content.Context;
import android.os.Build;
import android.provider.Settings.Secure;
import android.telephony.TelephonyManager;
 
public class DeviceFactoty {
 
 
    // buildId
    public String m_szDevIDShortMaker() {
        String m_szDevIDShort = "35";
 
        m_szDevIDShort += Build.BOARD.length() % 10 + Build.BRAND.length() % 10
                + Build.CPU_ABI.length() % 10 + Build.DEVICE.length() % 10
                + Build.DISPLAY.length() % 10 + Build.HOST.length() % 10
                + Build.ID.length() % 10 + Build.MANUFACTURER.length() % 10
                + Build.MODEL.length() % 10 + Build.PRODUCT.length() % 10
                + Build.TAGS.length() % 10 + Build.TYPE.length() % 10
                + Build.USER.length() % 10 + "";
 
        return m_szDevIDShort;
    }
 
 
 
    public String currentDeviceMark(Context context) {final TelephonyManager tm = (TelephonyManager) context
                .getSystemService(Context.TELEPHONY_SERVICE);
 
        final String tmDevice, tmSerial, androidId;
        tmDevice = "" + tm.getDeviceId();
        tmSerial = "" + tm.getSimSerialNumber();
        androidId = ""
                + android.provider.Settings.Secure.getString(EPApp.getApp()
                        .getContentResolver(), Secure.ANDROID_ID);
        String serial = "";
        if (Build.VERSION.SDK_INT > Build.VERSION_CODES.FROYO){serial = Build.SERIAL;}
        String m_szLongID = tmDevice + tmSerial + androidId + serial
                + m_szDevIDShortMaker();
        MessageDigest m = null;
        try {m = MessageDigest.getInstance("MD5");
        } catch (NoSuchAlgorithmException e) {e.printStackTrace();
        }
        m.update(m_szLongID.getBytes(), 0, m_szLongID.length());
        // get md5 bytes
        byte p_md5Data[] = m.digest();
        // create a hex string
        String m_szUniqueID = new String();
        for (int i = 0; i < p_md5Data.length; i++) {int b = (0xFF & p_md5Data[i]);
            // if it is a single digit, make sure it have 0 in front (proper padding)
            if (b <= 0xF)
                m_szUniqueID += "0";
            // add number to string
            m_szUniqueID += Integer.toHexString(b);
        } // hex string to uppercase
        return m_szUniqueID = m_szUniqueID.toUpperCase();}
}