public abstract class HttpTransport
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
fromcom.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
.
- For maximum backwards compatibility with older SDK's use
- Other Java environments
com.google.api.client.googleapis.javanet.GoogleNetHttpTransport
is included in google-api-cient 1.22.0, so easy to include.com.google.api.client.javanet.NetHttpTransport
is based on the HttpURLConnection built into the Java SDK, so it used to be 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.
Constructors
HttpTransport()
public HttpTransport()
Methods
buildRequest(String method, String url)
protected abstract LowLevelHttpRequest buildRequest(String method, String url)
Builds a low level HTTP request for the given HTTP method.
Parameters | |
---|---|
Name | Description |
method |
String HTTP method |
url |
String URL |
Returns | |
---|---|
Type | Description |
LowLevelHttpRequest |
new low level HTTP request |
Exceptions | |
---|---|
Type | Description |
IOException |
if HTTP method is not supported |
createRequestFactory()
public final HttpRequestFactory createRequestFactory()
Returns a new instance of an HTTP request factory based on this HTTP transport.
Returns | |
---|---|
Type | Description |
HttpRequestFactory |
new instance of an HTTP request factory |
createRequestFactory(HttpRequestInitializer initializer)
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.
Parameter | |
---|---|
Name | Description |
initializer |
HttpRequestInitializer HTTP request initializer or |
Returns | |
---|---|
Type | Description |
HttpRequestFactory |
new instance of an HTTP request factory |
isMtls()
public boolean isMtls()
Returns whether the transport is mTLS.
Returns | |
---|---|
Type | Description |
boolean |
boolean indicating if the transport is mTLS. |
shutdown()
public void shutdown()
Default implementation does nothing, but subclasses may override to possibly release allocated system resources or close connections.
Exceptions | |
---|---|
Type | Description |
IOException |
I/O exception |
supportsMethod(String method)
public boolean supportsMethod(String method)
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.
Parameter | |
---|---|
Name | Description |
method |
String HTTP method |
Returns | |
---|---|
Type | Description |
boolean |
Exceptions | |
---|---|
Type | Description |
IOException |
I/O exception |