实例_在文件中保留上次输入的类容

public class MainActivity extends Activity
{
private EditText et;

//
//创建活动时读取是否有上次保存的内容
//
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
et = (EditText) findViewById(R.id.et);

String inputText = load();
//
//if(!(inputText == null || inputText.length() == 0))
//android.text.TextUtils
//
if(!TextUtils.isEmpty(inputText))//empty  空的 adj
{
et.setText(inputText);
et.setSelection(inputText.length());
Toast.makeText(this, "Restoring succeeded", Toast.LENGTH_SHORT).show();
}

}

//
//销毁活动时在文件中保存内容
//
@Override
protected void onDestroy()
{
super.onDestroy();
String inputText = et.getText().toString();

save(inputText);
}

//
//保存
//
private void save(String inputText)
{
BufferedWriter bWriter = null;

try
{
bWriter = new BufferedWriter(new OutputStreamWriter(openFileOutput("data", Context.MODE_PRIVATE)));
bWriter.write(inputText);
} catch (IOException e)
{
e.printStackTrace();
} finally
{
if (bWriter != null)
{
try
{
bWriter.close();
} catch (IOException e)
{
e.printStackTrace();
}
}
}
}

//
//读取
//
private String load()
{
StringBuffer content = new StringBuffer();
BufferedReader bReader = null;
try
{
bReader = new BufferedReader(new InputStreamReader(openFileInput("data")));
String line = "";
while ((line = bReader.readLine()) != null)
{
content.append(line);
}
} catch (IOException e)
{
e.printStackTrace();
} finally
{
if(bReader != null)
{
try
{
bReader.close();
} catch (IOException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

return content.toString();
}
}