**Last updated**: 30 October 2025 | [**Change log**](/products/checkout/android/changelog/)

# Create `sessionState`

Create a `sessionState` by sending your customer's card details.

### `sessionState`

A `sessionState` is a unique identifier for your customer's card details, which is generated by the SDK.

#### Full Integration example

See our GitHub repository for the [full integration](https://github.com/Worldpay/access-checkout-android/blob/v1.2.0/checkout/sample/src/main/java/com/worldpay/access/checkout/MainActivity.kt) example.

## Implementing callbacks

Our SDK uses callbacks to notify you when your customer's card details have been converted into a `sessionState`.

### `SessionResponseListener`

You must create a class that implements our `SessionResponseListener`.

The `SessionResponseListener` receives notifications during the lifecycle of the request. The `SessionResponseListener` generates and returns the `sessionState`.

Here is an example of how you would create a class that implements our `SessionResponseListener`.

Kotlin

```java
class YourSessionResponseListener: SessionResponseListener {
    override fun onRequestStarted() {
        ...
    }
    
    override fun onRequestFinished(sessionState: String?, error: AccessCheckoutException?) {
        ....
    }
}
```

Java

```java
public class YourSessionResponseListener implements SessionResponseListener {
    @Override
    public void onRequestStarted() {
        ...
    }
    
    @Override
    public void onRequestFinished(@Nullable String sessionState, @Nullable AccessCheckoutException error) {
        ...
    }
}
```

details
summary
AccessCheckoutException
If there is an error, the error is returned by the `SessionResponseListener` through the `onRequestFinished(sessionState: String?, error: AccessCheckoutException?)` callback, this time with `sessionState` as `null` and error as a non-null error. See the table below for all the possible returned errors.
The following table of errors can be found in the enum class `com.worldpay.access.checkout.api.AccessCheckoutException.Error`

| HTTP Code | Error name | Message |
|  --- | --- | --- |
| 400 | `bodyIsNotJson` | The body within the request is not valid JSON. |
| 400 | `bodyIsEmpty` | The body within the request is empty. |
| 400 | `bodyDoesNotMatchSchema` | The JSON body provided does not match the expected schema. |
| 404 | `resourceNotFound` | Requested resource was not found. |
| 404 | `endpointNotFound` | Requested endpoint was not found. |
| 405 | `methodNotAllowed` | Requested method is not allowed. |
| 406 | `unsupportedAcceptHeader` | Accept header is not supported. |
| 415 | `unsupportedContentType` | Content-type header is not supported. |
| 500 | `internalErrorOccurred` | Internal server error. |
| 500 | `unknownError` | Unknown error. |


If you're presented with a `bodyDoesNotMatchSchema` error, a list of the broken validation rules is provided to help with debugging the problem.

`AccessCheckoutClientError` is the subclass used for the above issues.


```
data class AccessCheckoutClientError(
    val error: Error,
    override val message: String?,
    val validationRules: List<ValidationRule>? = null
) : AccessCheckoutException()
```

The `validationRules` list contains a list of `ValidationRule`s, which includes the error, a description message and the JSON path to the location where the error was caused.

data class ValidationRule(val errorName: ValidationRuleName, val message: String, val jsonPath: String)

## Initialize the SDK

Once you've created the class and extended the callback, you must initialize the SDK using the `AccessCheckoutClient` method.

To initialize the SDK, you must provide your `BaseURL`, `merchantID` and other parameters. See the table below for more information.

Here's an example of how you would initialize the SDK with the parameters and configurations you must include.

Kotlin

```java
override fun onStart(){
    super.onStart()
    
    val accessCheckoutClient=AccessCheckoutClient.init(
        getBaseUrl(),           // Base API URL 
        getMerchantID(),        // Your merchant ID
        sessionResponseListener,// SessionResponseListener
        applicationContext,     // Context
        lifecycleOwner          // LifecycleOwner
    )
}
```

Java

```java
@Override
protected void onStart(){
    super.onStart();
    
    AccessCheckoutClient accessCheckoutClient=AccessCheckoutClient.init(
    getBaseUrl(),           // Base API URL
    getMerchantID(),        // Your merchant ID
    sessionResponseListener,// SessionResponseListener
    applicationContext,     // Context
    lifecycleOwner          // LifecycleOwner
    );
}
```

| Methods | Descriptions |
|  --- | --- |
| `BaseURL` | For testing use : `https://try.access.worldpay.com/`For live use : `https://access.worldpay.com/` |
| `MerchantID` | Your unique merchant ID. |
| `sessionResponseListener` | The callback listener that returns your customer's `sessionState`. |
| `applicationContext` | [Android Context](https://developer.android.com/reference/android/content/Context) |
| `lifecycle` | [Android LifecycleOwner](https://developer.android.com/reference/android/arch/lifecycle/LifecycleOwner) |


## Submitting your customer's card details

Once your customer has finished entering their card details and clicks the submit button, you must invoke the `accessCheckoutClient.generateSessionState(...)` method.

Here's an example of what you should do when your customer clicks the submit button.

Kotlin

```java
...
submit.setOnClickListener {
    val pan = panView.getInsertedText()
    val month = cardExpiryText.getMonth()
    val year = cardExpiryText.getYear()
    val cvv = cardCVVText.getInsertedText()
    accessCheckoutClient.generateSessionState(pan, month, year, cvv)
}
```

Java

```java
...
submit.setOnClickListener(new View.OnClickListener() {
   @Override
    public void onClick(View v) {
      String pan = panView.getInsertedText();
      int month = cardExpiryText.getMonth();
      int year = cardExpiryText.getYear();
      String cvv = cardCVVText.getInsertedText();
      accessCheckoutClient.generateSessionState(pan, month, year, cvv);
  }
});
```

## Generate `sessionState`

### Generating the `sessionState`

The `sessionState` is returned in the response of the `onRequestFinished()` method, invoked in [`YourSessionResponseListener`](#sessionresponselistener) class.

Kotlin

```java
...
override fun onRequestFinished(sessionState: String?, error: AccessCheckoutException?) {
    ...
}
```

Java

```java
...
@Override
public void onRequestFinished(@Nullable String sessionState, @Nullable AccessCheckoutException error) {
    ...
}
```

### Create a Verified token

Once you've received a `sessionState` you must create a [verified token](/products/verified-tokens/create-verified-token#create-a-verified-token-request) to [take a payment](/products/card-payments/v6/authorize-a-payment#authorize-a-payment).

**Next steps**

[Verified token](/products/verified-tokens/create-verified-token)