[android] 保存文件到SD卡

package com.tsh.savefile.service;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStreamReader;
import java.util.HashMap;
import java.util.Map;

import android.content.Context;
import android.os.Environment;
import android.widget.Toast;

public class LoginService {
    /**
     * 保存用户名和方法的业务方法
     * @param context 上下文
     * @param username 用户名
     * @param password 方法
     * @return
     */
    public static boolean saveUserInfo(Context context,String username,String password){
        if(!Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
            Toast.makeText(context, "sd卡不可用", Toast.LENGTH_SHORT).show();
            return false;
        }
        File file=new File(Environment.getExternalStorageDirectory(),"/info1.txt");
        try {
            FileOutputStream fos=new FileOutputStream(file);
            String info=username+"##"+password;
            fos.write(info.getBytes());
            fos.close();
            return true;
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
        
    }
    /**
     * 读取
     * @return
     */
    public static Map<String,String> getSavedUserInfo(Context context){
        File file=new File(Environment.getExternalStorageDirectory(),"/info1.txt");
        try {
            FileInputStream fis=new FileInputStream(file);
            BufferedReader br=new BufferedReader(new InputStreamReader(fis));
            String[] res=br.readLine().split("##");
            Map<String, String> map=new HashMap<String,String>();
            map.put("username", res[0]);
            map.put("password", res[1]);
            return map;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
        
    }
}