# Class HttpsURLConnection

java.lang.Object
java.net.URLConnection
java.net.HttpURLConnection
javax.net.ssl.HttpsURLConnection

public abstract class HttpsURLConnection extends HttpURLConnection
`HttpsURLConnection` extends `HttpURLConnection` with support for https-specific features.

See http://www.w3.org/pub/WWW/Protocols/ and RFC 2818 for more details on the https specification.

This class uses `HostnameVerifier` and `SSLSocketFactory`. There are default implementations defined for both classes. However, the implementations can be replaced on a per-class (static) or per-instance basis. All new `HttpsURLConnection`s instances will be assigned the "default" static values at instance creation, but they can be overridden by calling the appropriate per-instance set method(s) before `connect`ing.

Since:
  1.4

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `protected HostnameVerifier`
  `hostnameVerifier`
  The `hostnameVerifier` for this object.

  ### Fields declared in class HttpURLConnection

  `chunkLength, fixedContentLength, fixedContentLengthLong, HTTP_ACCEPTED, HTTP_BAD_GATEWAY, HTTP_BAD_METHOD, HTTP_BAD_REQUEST, HTTP_CLIENT_TIMEOUT, HTTP_CONFLICT, HTTP_CREATED, HTTP_ENTITY_TOO_LARGE, HTTP_FORBIDDEN, HTTP_GATEWAY_TIMEOUT, HTTP_GONE, HTTP_INTERNAL_ERROR, HTTP_LENGTH_REQUIRED, HTTP_MOVED_PERM, HTTP_MOVED_TEMP, HTTP_MULT_CHOICE, HTTP_NO_CONTENT, HTTP_NOT_ACCEPTABLE, HTTP_NOT_AUTHORITATIVE, HTTP_NOT_FOUND, HTTP_NOT_IMPLEMENTED, HTTP_NOT_MODIFIED, HTTP_OK, HTTP_PARTIAL, HTTP_PAYMENT_REQUIRED, HTTP_PRECON_FAILED, HTTP_PROXY_AUTH, HTTP_REQ_TOO_LONG, HTTP_RESET, HTTP_SEE_OTHER, HTTP_SERVER_ERROR, HTTP_UNAUTHORIZED, HTTP_UNAVAILABLE, HTTP_UNSUPPORTED_TYPE, HTTP_USE_PROXY, HTTP_VERSION, instanceFollowRedirects, method, responseCode, responseMessage`

  ### Fields declared in class URLConnection

  `allowUserInteraction, connected, doInput, doOutput, ifModifiedSince, url, useCaches`

- ## Constructor Summary

  Constructors
  Modifier
  Constructor
  Description
  `protected`
  `HttpsURLConnection(URL url)`
  Creates an `HttpsURLConnection` using the URL specified.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `abstract String`
  `getCipherSuite()`
  Returns the cipher suite in use on this connection.
  `static HostnameVerifier`
  `getDefaultHostnameVerifier()`
  Gets the default `HostnameVerifier` that is inherited by new instances of this class.
  `static SSLSocketFactory`
  `getDefaultSSLSocketFactory()`
  Gets the default static `SSLSocketFactory` that is inherited by new instances of this class.
  `HostnameVerifier`
  `getHostnameVerifier()`
  Gets the `HostnameVerifier` in place on this instance.
  `abstract Certificate[]`
  `getLocalCertificates()`
  Returns the certificate(s) that were sent to the server during handshaking.
  `Principal`
  `getLocalPrincipal()`
  Returns the principal that was sent to the server during handshaking.
  `Principal`
  `getPeerPrincipal()`
  Returns the server's principal which was established as part of defining the session.
  `abstract Certificate[]`
  `getServerCertificates()`
  Returns the server's certificate chain which was established as part of defining the session.
  `Optional<SSLSession>`
  `getSSLSession()`
  Returns an `Optional` containing the `SSLSession` in use on this connection.
  `SSLSocketFactory`
  `getSSLSocketFactory()`
  Gets the SSL socket factory to be used when creating sockets for secure https URL connections.
  `static void`
  `setDefaultHostnameVerifier(HostnameVerifier v)`
  Sets the default `HostnameVerifier` inherited by a new instance of this class.
  `static void`
  `setDefaultSSLSocketFactory(SSLSocketFactory sf)`
  Sets the default `SSLSocketFactory` inherited by new instances of this class.
  `void`
  `setHostnameVerifier(HostnameVerifier v)`
  Sets the `HostnameVerifier` for this instance.
  `void`
  `setSSLSocketFactory(SSLSocketFactory sf)`
  Sets the `SSLSocketFactory` to be used when this instance creates sockets for secure https URL connections.

  ### Methods declared in class HttpURLConnection

  `disconnect, getErrorStream, getFollowRedirects, getHeaderField, getHeaderFieldKey, getInstanceFollowRedirects, getPermission, getRequestMethod, getResponseCode, getResponseMessage, setAuthenticator, setChunkedStreamingMode, setFixedLengthStreamingMode, setFixedLengthStreamingMode, setFollowRedirects, setInstanceFollowRedirects, setRequestMethod, usingProxy`

  ### Methods declared in class URLConnection

  `addRequestProperty, connect, getAllowUserInteraction, getConnectTimeout, getContent, getContent, getContentEncoding, getContentLength, getContentLengthLong, getContentType, getDate, getDefaultAllowUserInteraction, getDefaultRequestProperty, getDefaultUseCaches, getDefaultUseCaches, getDoInput, getDoOutput, getExpiration, getFileNameMap, getHeaderField, getHeaderFieldDate, getHeaderFieldInt, getHeaderFieldLong, getHeaderFields, getIfModifiedSince, getInputStream, getLastModified, getOutputStream, getReadTimeout, getRequestProperties, getRequestProperty, getURL, getUseCaches, guessContentTypeFromName, guessContentTypeFromStream, setAllowUserInteraction, setConnectTimeout, setContentHandlerFactory, setDefaultAllowUserInteraction, setDefaultRequestProperty, setDefaultUseCaches, setDefaultUseCaches, setDoInput, setDoOutput, setFileNameMap, setIfModifiedSince, setReadTimeout, setRequestProperty, setUseCaches, toString`

  ### Methods declared in class Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

- ## Field Details

  - ### hostnameVerifier

    protected HostnameVerifier hostnameVerifier
    The `hostnameVerifier` for this object.

- ## Constructor Details

  - ### HttpsURLConnection

    protected HttpsURLConnection(URL url)
    Creates an `HttpsURLConnection` using the URL specified.
    Parameters:
      `url` - the URL

- ## Method Details

  - ### getCipherSuite

    public abstract String getCipherSuite()
    Returns the cipher suite in use on this connection.
    Returns:
      the cipher suite
    Throws:
      `IllegalStateException` - if this method is called before the connection has been established.

  - ### getLocalCertificates

    public abstract Certificate[] getLocalCertificates()
    Returns the certificate(s) that were sent to the server during handshaking.

    Note: This method is useful only when using certificate-based cipher suites.

    When multiple certificates are available for use in a handshake, the implementation chooses what it considers the "best" certificate chain available, and transmits that to the other side. This method allows the caller to know which certificate chain was actually sent.

    Returns:
      an ordered array of certificates, with the client's own certificate first followed by any certificate authorities. If no certificates were sent, then null is returned.
    Throws:
      `IllegalStateException` - if this method is called before the connection has been established.
    See Also:
      - `getLocalPrincipal()`

  - ### getServerCertificates

    public abstract Certificate[] getServerCertificates() throws SSLPeerUnverifiedException
    Returns the server's certificate chain which was established as part of defining the session.

    Note: This method can be used only when using certificate-based cipher suites; using it with non-certificate-based cipher suites, such as Kerberos, will throw an SSLPeerUnverifiedException.

    Note: The returned value may not be a valid certificate chain and should not be relied on for trust decisions.

    Returns:
      an ordered array of server certificates, with the peer's own certificate first followed by any certificate authorities.
    Throws:
      `SSLPeerUnverifiedException` - if the peer is not verified.
      `IllegalStateException` - if this method is called before the connection has been established.
    See Also:
      - `getPeerPrincipal()`

  - ### getPeerPrincipal

    public Principal getPeerPrincipal() throws SSLPeerUnverifiedException
    Returns the server's principal which was established as part of defining the session.

    Note: Subclasses should override this method. If not overridden, it will default to returning the X500Principal of the server's end-entity certificate for certificate-based ciphersuites, or throw an SSLPeerUnverifiedException for non-certificate based ciphersuites, such as Kerberos.

    Returns:
      the server's principal. Returns an X500Principal of the end-entity certificate for X509-based cipher suites, and KerberosPrincipal for Kerberos cipher suites.
    Throws:
      `SSLPeerUnverifiedException` - if the peer was not verified
      `IllegalStateException` - if this method is called before the connection has been established.
    Since:
      1.5
    See Also:
      - `getServerCertificates()`
      - `getLocalPrincipal()`

  - ### getLocalPrincipal

    public Principal getLocalPrincipal()
    Returns the principal that was sent to the server during handshaking.

    Note: Subclasses should override this method. If not overridden, it will default to returning the X500Principal of the end-entity certificate that was sent to the server for certificate-based ciphersuites or, return null for non-certificate based ciphersuites, such as Kerberos.

    Returns:
      the principal sent to the server. Returns an X500Principal of the end-entity certificate for X509-based cipher suites, and KerberosPrincipal for Kerberos cipher suites. If no principal was sent, then null is returned.
    Throws:
      `IllegalStateException` - if this method is called before the connection has been established.
    Since:
      1.5
    See Also:
      - `getLocalCertificates()`
      - `getPeerPrincipal()`

  - ### setDefaultHostnameVerifier

    public static void setDefaultHostnameVerifier(HostnameVerifier v)
    Sets the default `HostnameVerifier` inherited by a new instance of this class.

    If this method is not called, the default `HostnameVerifier` assumes the connection should not be permitted.

    Parameters:
      `v` - the default host name verifier
    Throws:
      `IllegalArgumentException` - if the `HostnameVerifier` parameter is null.
    See Also:
      - `getDefaultHostnameVerifier()`

  - ### getDefaultHostnameVerifier

    public static HostnameVerifier getDefaultHostnameVerifier()
    Gets the default `HostnameVerifier` that is inherited by new instances of this class.
    Returns:
      the default host name verifier
    See Also:
      - `setDefaultHostnameVerifier(HostnameVerifier)`

  - ### setHostnameVerifier

    public void setHostnameVerifier(HostnameVerifier v)
    Sets the `HostnameVerifier` for this instance.

    New instances of this class inherit the default static hostname verifier set by `setDefaultHostnameVerifier`. Calls to this method replace this object's `HostnameVerifier`.

    Parameters:
      `v` - the host name verifier
    Throws:
      `IllegalArgumentException` - if the `HostnameVerifier` parameter is null.
    See Also:
      - `getHostnameVerifier()`
      - `setDefaultHostnameVerifier(HostnameVerifier)`

  - ### getHostnameVerifier

    public HostnameVerifier getHostnameVerifier()
    Gets the `HostnameVerifier` in place on this instance.
    Returns:
      the host name verifier
    See Also:
      - `setHostnameVerifier(HostnameVerifier)`
      - `setDefaultHostnameVerifier(HostnameVerifier)`

  - ### setDefaultSSLSocketFactory

    public static void setDefaultSSLSocketFactory(SSLSocketFactory sf)
    Sets the default `SSLSocketFactory` inherited by new instances of this class.

    The socket factories are used when creating sockets for secure https URL connections.

    Parameters:
      `sf` - the default SSL socket factory
    Throws:
      `IllegalArgumentException` - if the SSLSocketFactory parameter is null.
    See Also:
      - `getDefaultSSLSocketFactory()`

  - ### getDefaultSSLSocketFactory

    public static SSLSocketFactory getDefaultSSLSocketFactory()
    Gets the default static `SSLSocketFactory` that is inherited by new instances of this class.

    The socket factories are used when creating sockets for secure https URL connections.

    Returns:
      the default `SSLSocketFactory`
    See Also:
      - `setDefaultSSLSocketFactory(SSLSocketFactory)`

  - ### setSSLSocketFactory

    public void setSSLSocketFactory(SSLSocketFactory sf)
    Sets the `SSLSocketFactory` to be used when this instance creates sockets for secure https URL connections.

    New instances of this class inherit the default static `SSLSocketFactory` set by `setDefaultSSLSocketFactory`. Calls to this method replace this object's `SSLSocketFactory`.

    Parameters:
      `sf` - the SSL socket factory
    Throws:
      `IllegalArgumentException` - if the `SSLSocketFactory` parameter is null.
    See Also:
      - `getSSLSocketFactory()`

  - ### getSSLSocketFactory

    public SSLSocketFactory getSSLSocketFactory()
    Gets the SSL socket factory to be used when creating sockets for secure https URL connections.
    Returns:
      the `SSLSocketFactory`
    See Also:
      - `setSSLSocketFactory(SSLSocketFactory)`

  - ### getSSLSession

    public Optional<SSLSession> getSSLSession()
    Returns an `Optional` containing the `SSLSession` in use on this connection. Returns an empty `Optional` if the underlying implementation does not support this method.
    Implementation Requirements:
      For compatibility, the default implementation of this method returns an empty `Optional`. Subclasses should override this method with an appropriate implementation since an application may need to access additional parameters associated with the SSL session.
    Returns:
      an `Optional` containing the `SSLSession` in use on this connection.
    Throws:
      `IllegalStateException` - if this method is called before the connection has been established
    Since:
      12
    See Also:
      - `SSLSession`