java我想将字符串存储到存储器中，这样每当我重新打开应用程序时，字符串都应该在那里进行编辑

Question

我希望将两个用户输入字符串（ip和端口）保存到存储器中，以便在我输入并点击保存按钮后，即使在关闭并重新打开应用程序后，它们也应该在存储器中

public class MainActivity extends AppCompatActivity {

public static String p = "port number";
public static String u = "url/ip ";
public static String Mypreferences = "myprefs";
Activity context;
EditText iptxt,porttxt;
Button save;
SharedPreferences sharedPreferences;

u/Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
iptxt=(EditText)findViewById(R.id.txturl);
porttxt=(EditText)findViewById(R.id.txtport);
save = (Button)findViewById(R.id.btn1);
sharedPreferences = getSharedPreferences(Mypreferences,context.MODE_PRIVATE);
save.setOnClickListener(new View.OnClickListener() {
u/Override
public void onClick (View v ) {
String ip = iptxt.getText().toString();
String port = porttxt.getText().toString();
String clientId = MqttClient.generateClientId();
MqttAndroidClient client =
new MqttAndroidClient(context.getApplicationContext(), "tcp://"+ip +port,
clientId);
try {
IMqttToken token = client.connect();
token.setActionCallback(new IMqttActionListener() {
u/Override
public void onSuccess(IMqttToken asyncActionToken) {
// We are connected
//Log.d(TAG, "onSuccess");
}

u/Override
public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
// Something went wrong e.g. connection timeout or firewall problems
//Log.d(TAG, "onFailure");
}
});
} catch (MqttException e) {
e.printStackTrace();
}
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString(p,port);
editor.putString(u,ip);
editor.commit();
ip = sharedPreferences.getString(u,"defaul if empty");
port = sharedPreferences.getString(p,"dfault ");
}

});
}

}