Java中如何实现系统存储

btn_ok.setOnClickListener(new OnClickListener() {

           @Override

           publicvoid onClick(View v) {

              String user = et_user.getText().toString().trim();

              String pwd = et_pwd.getText().toString().trim();

              if(user.isEmpty()||pwd.isEmpty()){

                  Toast.makeText(getApplicationContext(),"不能为空", 200).show();

              }else{

                  String name="data.txt";

                  Stringcontent=user+"="+pwd;

// StringBuffer sb = newStringBuffer();

              String content =sb.append(userName).append("=").append(password).toString();

try {

                     FileOutputStream  fos=openFileOutput(name, MODE_PRIVATE);

                     fos.write(content.getBytes());

                     fos.close();

                     Toast.makeText(getApplicationContext(),"保存成功", 200).show();

                  } catch (Exception e) {

                     // TODO Auto-generated catch block

                     e.printStackTrace();

                  }

              }

           }

btn_show.setOnClickListener(new OnClickListener() {

           @Override

           publicvoid onClick(View v) {

              String name="data.txt";

              try {

                  FileInputStream  fis=openFileInput(name);

                  BufferedReaderbr=new BufferedReader(new InputStreamReader(fis));

                  //读取文档的数据

                  String content =br.readLine();

                  //拆分字符串

                  String[] strs =content.split("=");

                  //显示的数据

                  if(!content.isEmpty()){

                     et_user.setText(strs[0]);

                     et_pwd.setText(strs[1]);

                  }

              } catch (Exception e) {

                  // TODO Auto-generated catch block

                  e.printStackTrace();

              }  

           }