Added in [API level 37](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  
Also in [C Extensions 22](https://developer.android.com/sdkExtensions) Summary: [Ctors](https://developer.android.com/reference/android/net/ssl/EchConfigMismatchException#pubctors) \| [Methods](https://developer.android.com/reference/android/net/ssl/EchConfigMismatchException#pubmethods) \| [Inherited Methods](https://developer.android.com/reference/android/net/ssl/EchConfigMismatchException#inhmethods)

# EchConfigMismatchException

*** ** * ** ***

` public class EchConfigMismatchException `   
` ` ` ` ` ` ` ` ` extends https://developer.android.com/reference/javax/net/ssl/SSLException ` ` `

|---|---|---|---|---|---|
| [java.lang.Object](https://developer.android.com/reference/java/lang/Object) ||||||
| ↳ | [java.lang.Throwable](https://developer.android.com/reference/java/lang/Throwable) |||||
|   | ↳ | [java.lang.Exception](https://developer.android.com/reference/java/lang/Exception) ||||
|   |   | ↳ | [java.io.IOException](https://developer.android.com/reference/java/io/IOException) |||
|   |   |   | ↳ | [javax.net.ssl.SSLException](https://developer.android.com/reference/javax/net/ssl/SSLException) ||
|   |   |   |   | ↳ | android.net.ssl.EchConfigMismatchException |

<br />

*** ** * ** ***

Exception thrown when the provided ECH (Encrypted Client Hello) config does not match the server.

Before accessing the retry configuration, clients **must** call `https://developer.android.com/reference/android/net/ssl/EchConfigMismatchException#getPublicHostname()` and verify that the hostname matches the connection hostname (using their preferred `https://developer.android.com/reference/javax/net/ssl/HostnameVerifier`). If the returned hostname is `null`, any provided retry configuration must be ignored.

Clients can then attempt to establish a new connection, using the provided retry `https://developer.android.com/reference/android/net/ssl/EchConfigList`, if available. A retry `https://developer.android.com/reference/android/net/ssl/EchConfigList` may not be available if the server has not provided any.

## Summary

| ### Public constructors ||
|---|---|
| ` https://developer.android.com/reference/android/net/ssl/EchConfigMismatchException#EchConfigMismatchException(java.lang.String,%20java.lang.String,%20android.net.ssl.EchConfigList)(https://developer.android.com/reference/java/lang/String message, https://developer.android.com/reference/java/lang/String publicName, https://developer.android.com/reference/android/net/ssl/EchConfigList echRetryConfigList) ` Constructs a new `EchConfigMismatchException`. |

| ### Public methods ||
|---|---|
| ` https://developer.android.com/reference/java/lang/String` | ` https://developer.android.com/reference/android/net/ssl/EchConfigMismatchException#getPublicHostname()() ` Returns the hostname that should be used for verification. |
| ` https://developer.android.com/reference/android/net/ssl/EchConfigList` | ` https://developer.android.com/reference/android/net/ssl/EchConfigMismatchException#getRetryConfigList()() ` Returns the `https://developer.android.com/reference/android/net/ssl/EchConfigList` provided by the server for retrying the connection, or `null` if no retry configuration was set by the server. |
| ` boolean` | ` https://developer.android.com/reference/android/net/ssl/EchConfigMismatchException#hasRetryConfigList()() ` Returns `true` if a retry `https://developer.android.com/reference/android/net/ssl/EchConfigList` is available, false otherwise. |

### Inherited methods

From class ` https://developer.android.com/reference/java/lang/Throwable ` ` final void` ` https://developer.android.com/reference/java/lang/Throwable#addSuppressed(java.lang.Throwable)(https://developer.android.com/reference/java/lang/Throwable exception) `

Appends the specified exception to the exceptions that were suppressed in order to deliver this exception.
` https://developer.android.com/reference/java/lang/Throwable` ` https://developer.android.com/reference/java/lang/Throwable#fillInStackTrace()() `

Fills in the execution stack trace.
` https://developer.android.com/reference/java/lang/Throwable` ` https://developer.android.com/reference/java/lang/Throwable#getCause()() `

Returns the cause of this throwable or `null` if the cause is nonexistent or unknown.
` https://developer.android.com/reference/java/lang/String` ` https://developer.android.com/reference/java/lang/Throwable#getLocalizedMessage()() `

Creates a localized description of this throwable.
` https://developer.android.com/reference/java/lang/String` ` https://developer.android.com/reference/java/lang/Throwable#getMessage()() `

Returns the detail message string of this throwable.
` https://developer.android.com/reference/java/lang/StackTraceElement` ` https://developer.android.com/reference/java/lang/Throwable#getStackTrace()() `

Provides programmatic access to the stack trace information printed by `https://developer.android.com/reference/java/lang/Throwable#printStackTrace()`.
` final https://developer.android.com/reference/java/lang/Throwable` ` https://developer.android.com/reference/java/lang/Throwable#getSuppressed()() `

Returns an array containing all of the exceptions that were suppressed, typically by the `try`-with-resources statement, in order to deliver this exception.
` https://developer.android.com/reference/java/lang/Throwable` ` https://developer.android.com/reference/java/lang/Throwable#initCause(java.lang.Throwable)(https://developer.android.com/reference/java/lang/Throwable cause) `

Initializes the *cause* of this throwable to the specified value.
` void` ` https://developer.android.com/reference/java/lang/Throwable#printStackTrace()() `

Prints this throwable and its backtrace to the standard error stream.
` void` ` https://developer.android.com/reference/java/lang/Throwable#printStackTrace(java.io.PrintWriter)(https://developer.android.com/reference/java/io/PrintWriter s) `

Prints this throwable and its backtrace to the specified print writer.
` void` ` https://developer.android.com/reference/java/lang/Throwable#printStackTrace(java.io.PrintStream)(https://developer.android.com/reference/java/io/PrintStream s) `

Prints this throwable and its backtrace to the specified print stream.
` void` ` https://developer.android.com/reference/java/lang/Throwable#setStackTrace(java.lang.StackTraceElement[])(https://developer.android.com/reference/java/lang/StackTraceElement stackTrace) `

Sets the stack trace elements that will be returned by `https://developer.android.com/reference/java/lang/Throwable#getStackTrace()` and printed by `https://developer.android.com/reference/java/lang/Throwable#printStackTrace()` and related methods.
` https://developer.android.com/reference/java/lang/String` ` https://developer.android.com/reference/java/lang/Throwable#toString()() `

Returns a short description of this throwable.
From class ` https://developer.android.com/reference/java/lang/Object ` ` https://developer.android.com/reference/java/lang/Object` ` https://developer.android.com/reference/java/lang/Object#clone()() `

Creates and returns a copy of this object.
` boolean` ` https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object)(https://developer.android.com/reference/java/lang/Object obj) `

Indicates whether some other object is "equal to" this one.
` void` ` https://developer.android.com/reference/java/lang/Object#finalize()() `

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
` final https://developer.android.com/reference/java/lang/Class<?>` ` https://developer.android.com/reference/java/lang/Object#getClass()() `

Returns the runtime class of this `Object`.
` int` ` https://developer.android.com/reference/java/lang/Object#hashCode()() `

Returns a hash code value for the object.
` final void` ` https://developer.android.com/reference/java/lang/Object#notify()() `

Wakes up a single thread that is waiting on this object's monitor.
` final void` ` https://developer.android.com/reference/java/lang/Object#notifyAll()() `

Wakes up all threads that are waiting on this object's monitor.
` https://developer.android.com/reference/java/lang/String` ` https://developer.android.com/reference/java/lang/Object#toString()() `

Returns a string representation of the object.
` final void` ` https://developer.android.com/reference/java/lang/Object#wait(long,%20int)(long timeoutMillis, int nanos) `

Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*, or until a certain amount of real time has elapsed.
` final void` ` https://developer.android.com/reference/java/lang/Object#wait(long)(long timeoutMillis) `

Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*, or until a certain amount of real time has elapsed.
` final void` ` https://developer.android.com/reference/java/lang/Object#wait()() `

Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*.

## Public constructors

### EchConfigMismatchException

Added in [API level 37](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  
Also in [C Extensions 22](https://developer.android.com/sdkExtensions)

```
public EchConfigMismatchException (String message, 
                String publicName, 
                EchConfigList echRetryConfigList)
```

Constructs a new `EchConfigMismatchException`.

<br />

| Parameters ||
|---|---|
| `message` | `String`: the detail message. This value may be `null`. <br /> |
| `publicName` | `String`: the hostname that must be used for verification, or `null` if the server did not provide a valid public name. <br /> |
| `echRetryConfigList` | `EchConfigList`: the `https://developer.android.com/reference/android/net/ssl/EchConfigList` provided by the server for retrying the connection, or `null` if no retry configuration was set by the server. <br /> |

## Public methods

### getPublicHostname

Added in [API level 37](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  
Also in [C Extensions 22](https://developer.android.com/sdkExtensions)

```
public String getPublicHostname ()
```

Returns the hostname that should be used for verification. This method must be called before interpreting the retry config list, returned by `https://developer.android.com/reference/android/net/ssl/EchConfigMismatchException#getRetryConfigList()`. For more details see section 6.1.7 "Authenticating for the Public Name" in RFC TLS Encrypted Client Hello (draft-ietf-tls-esni-25).

<br />

| Returns ||
|---|---|
| `https://developer.android.com/reference/java/lang/String` | This value may be `null`. <br /> |

### getRetryConfigList

Added in [API level 37](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  
Also in [C Extensions 22](https://developer.android.com/sdkExtensions)

```
public EchConfigList getRetryConfigList ()
```

Returns the `https://developer.android.com/reference/android/net/ssl/EchConfigList` provided by the server for retrying the connection, or `null` if no retry configuration was set by the server. Prior to reading this value, the client **must** verify that the certificate is valid for the name returned by `https://developer.android.com/reference/android/net/ssl/EchConfigMismatchException#getPublicHostname()`.

<br />

| Returns ||
|---|---|
| `https://developer.android.com/reference/android/net/ssl/EchConfigList` | <br /> |

### hasRetryConfigList

Added in [API level 37](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  
Also in [C Extensions 22](https://developer.android.com/sdkExtensions)

```
public boolean hasRetryConfigList ()
```

Returns `true` if a retry `https://developer.android.com/reference/android/net/ssl/EchConfigList` is available, false otherwise.

<br />

| Returns ||
|---|---|
| `boolean` | <br /> |