Class HttpTransport

  • Direct Known Subclasses:
    ApacheHttpTransport, MockHttpTransport, NetHttpTransport

    public abstract class HttpTransport
    extends Object
    Thread-safe abstract HTTP transport.

    Implementation is thread-safe, and sub-classes must be thread-safe. For maximum efficiency, applications should use a single globally-shared instance of the HTTP transport.

    The recommended concrete implementation HTTP transport library to use depends on what environment you are running in:

    • Google App Engine: use com.google.api.client.extensions.appengine.http.UrlFetchTransport.
      • com.google.api.client.apache.ApacheHttpTransport doesn't work on App Engine because the Apache HTTP Client opens its own sockets (though in theory there are ways to hack it to work on App Engine that might work).
      • com.google.api.client.javanet.NetHttpTransport is discouraged due to a bug in the App Engine SDK itself in how it parses HTTP headers in the response.
    • Android:
      • For maximum backwards compatibility with older SDK's use newCompatibleTransport from com.google.api.client.extensions.android.http.AndroidHttp (read its JavaDoc for details).
      • If your application is targeting Gingerbread (SDK 2.3) or higher, simply use com.google.api.client.javanet.NetHttpTransport.
    • Other Java environments
      • com.google.api.client.javanet.NetHttpTransport is based on the HttpURLConnection built into the Java SDK, so it is normally the preferred choice.
      • com.google.api.client.apache.ApacheHttpTransport is a good choice for users of the Apache HTTP Client, especially if you need some of the configuration options available in that library.

    Some HTTP transports do not support all HTTP methods. Use supportsMethod(String) to check if a certain HTTP method is supported. Calling buildRequest() on a method that is not supported will result in an IllegalArgumentException.

    Subclasses should override supportsMethod(String) and buildRequest(String, String) to build requests and specify which HTTP methods are supported.

    Since:
    1.0
    Author:
    Yaniv Inbar
    • Constructor Detail

      • HttpTransport

        public HttpTransport()
    • Method Detail

      • createRequestFactory

        public final HttpRequestFactory createRequestFactory()
        Returns a new instance of an HTTP request factory based on this HTTP transport.
        Returns:
        new instance of an HTTP request factory
        Since:
        1.4
      • createRequestFactory

        public final HttpRequestFactory createRequestFactory​(HttpRequestInitializer initializer)
        Returns a new instance of an HTTP request factory based on this HTTP transport with the given HTTP request initializer.
        Parameters:
        initializer - HTTP request initializer or null for none
        Returns:
        new instance of an HTTP request factory
        Since:
        1.4
      • supportsMethod

        public boolean supportsMethod​(String method)
                               throws IOException
        Returns whether a specified HTTP method is supported by this transport.

        Default implementation returns true if and only if the request method is "DELETE", "GET", "POST", or "PUT". Subclasses should override.

        Parameters:
        method - HTTP method
        Throws:
        IOException - I/O exception
        Since:
        1.12
      • shutdown

        public void shutdown()
                      throws IOException
        Default implementation does nothing, but subclasses may override to possibly release allocated system resources or close connections.
        Throws:
        IOException - I/O exception
        Since:
        1.4