Proyectos de Subversion Android Microlearning

package com.cesams.twogetskills.library;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.RandomAccessFile;

import java.util.UUID;

import android.content.Context;

public class UniqueID {

    private static String sID = null;

    private static final String INSTALLATION = "TwoGetSkillsID.dat";

    public synchronized static String id(Context context) {

        if (sID == null) {

            File installation = new File(context.getFilesDir(), INSTALLATION);

            try {

                if (!installation.exists())

                    writeInstallationFile(installation);

                sID = readInstallationFile(installation);

            } catch (Exception e) {

                throw new RuntimeException(e);

            }

        }

        return sID;

    }

    private static String readInstallationFile(File installation) throws IOException {

        RandomAccessFile f = new RandomAccessFile(installation, "r");

        byte[] bytes = new byte[(int) f.length()];

        f.readFully(bytes);

        f.close();

        return new String(bytes);

    }

    private static void writeInstallationFile(File installation) throws IOException {

        FileOutputStream out = new FileOutputStream(installation);

        String id = UUID.randomUUID().toString();

        out.write(id.getBytes());

        out.close();

    }

}