winterwell.jtwitter

Class URLConnectionHttpClient

java.lang.Object

winterwell.jtwitter.URLConnectionHttpClient

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, Twitter.IHttpClient

Direct Known Subclasses:

BearerAuthHttpClient, OAuthSignpostClient

public class URLConnectionHttpClient
extends java.lang.Object
implements Twitter.IHttpClient, java.io.Serializable, java.lang.Cloneable

A simple http client that uses the built in URLConnection class.

Provides Twitter-focused error-handling, generating the right TwitterException. Also has a retry-on-error mode which can help smooth out Twitter's sometimes intermittent service. See setRetryOnError(boolean).

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.String	name
protected int	timeout

Constructor Summary

Constructors

Constructor and Description
URLConnectionHttpClient()
URLConnectionHttpClient(java.lang.String name, java.lang.String password)

Method Summary

Modifier and Type	Method and Description
boolean	canAuthenticate() Whether this client is setup to do authentication when contacting the Twitter server.
protected java.lang.String	checkRateLimit(java.lang.String url)
URLConnectionHttpClient	clone() Identical to copy()
java.net.HttpURLConnection	connect(java.lang.String url, java.util.Map<java.lang.String,java.lang.String> vars, boolean authenticate) Lower-level GET method.
Twitter.IHttpClient	copy()
java.lang.String	delete(java.lang.String uri, boolean authenticate) Send an HTTP DELETE request and return the response body.
protected void	disconnect(java.net.HttpURLConnection connection)
java.lang.String	getHeader(java.lang.String headerName) Fetch a header from the last http request.
java.lang.String	getPage(java.lang.String url, java.util.Map<java.lang.String,java.lang.String> vars, boolean authenticate) Send an HTTP GET request and return the response body.
RateLimit	getRateLimit(Twitter.KRequestType reqType)
java.util.Map<java.lang.String,RateLimit>	getRateLimits()
boolean	isRetryOnError() If true, will wait 1/2 second and make a 2nd request when presented with a server error (E50X).
java.lang.String	post(java.lang.String uri, java.util.Map<java.lang.String,java.lang.String> vars, boolean authenticate) Send an HTTP POST request and return the response body.
java.net.HttpURLConnection	post2_connect(java.lang.String uri, com.winterwell.json.JSONObject body) Lower-level POST method - stringifies JSON body instead of encoding vars
java.net.HttpURLConnection	post2_connect(java.lang.String uri, java.util.Map<java.lang.String,java.lang.String> vars) Lower-level POST method.
java.net.HttpURLConnection	post2_connect(java.lang.String uri, java.lang.String payload) Lower-level POST method - takes raw string for body
protected java.lang.String	post2_getPayload(java.util.Map<java.lang.String,java.lang.String> vars)
java.lang.String	postJSON(java.lang.String uri, com.winterwell.json.JSONObject body, boolean authenticate)
protected void	processHeaders(java.net.HttpURLConnection connection, java.lang.String resource) Cache headers for getHeader(String)
protected void	setAuthentication(java.net.URLConnection connection) Set a header for basic authentication login.
void	setGzip(boolean gzip) Set whether or not to request gzipped responses.
URLConnectionHttpClient	setHtmlImpliesError(boolean htmlImpliesError)
void	setMinRateLimit(int minRateLimit) Use this to protect your Twitter API rate-limit.
void	setRetryOnError(boolean retryOnError) False by default.
void	setTimeout(int millisecs) Set the timeout for a single get/post request.
java.lang.String	toString()
java.util.Map<java.lang.String,RateLimit>	updateRateLimits() Call Twitter to get the rate limit.

Methods inherited from class java.lang.Object

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

Field Detail

name

protected java.lang.String name

timeout

protected int timeout

Constructor Detail

URLConnectionHttpClient

public URLConnectionHttpClient()

URLConnectionHttpClient

public URLConnectionHttpClient(java.lang.String name,
                               java.lang.String password)

Method Detail

isRetryOnError

public boolean isRetryOnError()

Description copied from interface: Twitter.IHttpClient

If true, will wait 1/2 second and make a 2nd request when presented with a server error (E50X). Only retries once -- a 2nd fail will throw an exception. This policy handles most Twitter server glitches.

Specified by:

isRetryOnError in interface Twitter.IHttpClient

setGzip

public void setGzip(boolean gzip)

Set whether or not to request gzipped responses. The default is true.

setHtmlImpliesError

public URLConnectionHttpClient setHtmlImpliesError(boolean htmlImpliesError)

Parameters:

htmlImpliesError - default is true. If true, an html response will be treated as a server error & generate a TwitterException.E50X

Returns:

canAuthenticate

public boolean canAuthenticate()

Description copied from interface: Twitter.IHttpClient

Whether this client is setup to do authentication when contacting the Twitter server. Note: This is a fast method that does not call the server, so it does not check whether the access token or password is valid. See {Twitter#isValidLogin()} or Twitter_Account.verifyCredentials() if you need to check a login.

Specified by:

canAuthenticate in interface Twitter.IHttpClient

connect

public java.net.HttpURLConnection connect(java.lang.String url,
                                          java.util.Map<java.lang.String,java.lang.String> vars,
                                          boolean authenticate)
                                   throws java.io.IOException

Description copied from interface: Twitter.IHttpClient

Lower-level GET method.

Specified by:

connect in interface Twitter.IHttpClient

Returns:

Throws:

java.io.IOException

copy

public Twitter.IHttpClient copy()

Specified by:

copy in interface Twitter.IHttpClient

Returns:

a copy of this client. The copy can share structure, but it MUST be safe for passing to a new thread to be used in parallel with the original.

clone

public URLConnectionHttpClient clone()

Identical to copy()

Overrides:

clone in class java.lang.Object

disconnect

protected final void disconnect(java.net.HttpURLConnection connection)

getHeader

public java.lang.String getHeader(java.lang.String headerName)

Description copied from interface: Twitter.IHttpClient

Fetch a header from the last http request. This is inherently NOT thread safe. Headers from error messages should (probably) be cached.

Specified by:

getHeader in interface Twitter.IHttpClient

Returns:

header value, or null if unset

getRateLimits

public java.util.Map<java.lang.String,RateLimit> getRateLimits()

Specified by:

getRateLimits in interface Twitter.IHttpClient

Returns:

resource-to-rate-limit info, if known, or null. This method does _not_ perform a Twitter call.

updateRateLimits

public java.util.Map<java.lang.String,RateLimit> updateRateLimits()

Call Twitter to get the rate limit.

Returns:

latest rate limits (which will also be cached here for fast checks)

getPage

public final java.lang.String getPage(java.lang.String url,
                                      java.util.Map<java.lang.String,java.lang.String> vars,
                                      boolean authenticate)
                               throws TwitterException

Description copied from interface: Twitter.IHttpClient

Send an HTTP GET request and return the response body. Note that this will change all line breaks into system line breaks!

Specified by:

getPage in interface Twitter.IHttpClient

Parameters:

url - The uri to fetch

vars - get arguments to add to the uri

authenticate - If true, use authentication. The authentication method used depends on the implementation (basic-auth, OAuth). It is an error to use true if no authentication details have been set.

Throws:

TwitterException - for a variety of reasons

TwitterException.E404 - for resource-does-not-exist errors

getRateLimit

public RateLimit getRateLimit(Twitter.KRequestType reqType)

Specified by:

getRateLimit in interface Twitter.IHttpClient

See Also:

Twitter.IHttpClient.getRateLimits()

post

public final java.lang.String post(java.lang.String uri,
                                   java.util.Map<java.lang.String,java.lang.String> vars,
                                   boolean authenticate)
                            throws TwitterException

Description copied from interface: Twitter.IHttpClient

Send an HTTP POST request and return the response body.

Specified by:

post in interface Twitter.IHttpClient

Parameters:

uri - The uri to post to.

vars - The form variables to send. These are URL encoded before sending.

authenticate - If true, send user authentication

Returns:

The response from the server.

Throws:

TwitterException - for a variety of reasons

TwitterException.E404 - for resource-does-not-exist errors

postJSON

public final java.lang.String postJSON(java.lang.String uri,
                                       com.winterwell.json.JSONObject body,
                                       boolean authenticate)

Specified by:

postJSON in interface Twitter.IHttpClient

post2_connect

public java.net.HttpURLConnection post2_connect(java.lang.String uri,
                                                java.util.Map<java.lang.String,java.lang.String> vars)
                                         throws java.lang.Exception

Description copied from interface: Twitter.IHttpClient

Lower-level POST method.

Specified by:

post2_connect in interface Twitter.IHttpClient

Returns:

a freshly opened authorised connection

Throws:

TwitterException

java.lang.Exception

post2_connect

public java.net.HttpURLConnection post2_connect(java.lang.String uri,
                                                com.winterwell.json.JSONObject body)
                                         throws java.lang.Exception

Description copied from interface: Twitter.IHttpClient

Lower-level POST method - stringifies JSON body instead of encoding vars

Specified by:

post2_connect in interface Twitter.IHttpClient

Returns:

a freshly opened authorised connection

Throws:

TwitterException

java.lang.Exception

post2_connect

public java.net.HttpURLConnection post2_connect(java.lang.String uri,
                                                java.lang.String payload)
                                         throws java.lang.Exception

Description copied from interface: Twitter.IHttpClient

Lower-level POST method - takes raw string for body

Specified by:

post2_connect in interface Twitter.IHttpClient

Returns:

a freshly opened authorised connection

Throws:

TwitterException

java.lang.Exception

checkRateLimit

protected java.lang.String checkRateLimit(java.lang.String url)

post2_getPayload

protected java.lang.String post2_getPayload(java.util.Map<java.lang.String,java.lang.String> vars)

Parameters:

vars - Keys & values will be url-encoded. Special case: if there is 1 key "", then just the value is returned (url-encoded).

Returns:

delete

public final java.lang.String delete(java.lang.String uri,
                                     boolean authenticate)
                              throws TwitterException

Description copied from interface: Twitter.IHttpClient

Send an HTTP DELETE request and return the response body.

Specified by:

delete in interface Twitter.IHttpClient

Parameters:

uri - The uri to post to.

authenticate - If true, send user authentication

Returns:

The response from the server.

Throws:

TwitterException - for a variety of reasons

TwitterException.E404 - for resource-does-not-exist errors

processHeaders

protected final void processHeaders(java.net.HttpURLConnection connection,
                                    java.lang.String resource)

Cache headers for getHeader(String)

Parameters:

connection -

setAuthentication

protected void setAuthentication(java.net.URLConnection connection)

Set a header for basic authentication login.

setMinRateLimit

public void setMinRateLimit(int minRateLimit)

Use this to protect your Twitter API rate-limit. E.g. if you want to keep some credit in reserve for core activity. 0 by default. this http client object will start pre-emptively throwing rate-limit exceptions when it gets down to the specified level.

setRetryOnError

public void setRetryOnError(boolean retryOnError)

False by default. Setting this to true switches on a robustness workaround: when presented with a 50X server error, the system will wait 1/2 a second and make a second attempt.

Specified by:

setRetryOnError in interface Twitter.IHttpClient

setTimeout

public void setTimeout(int millisecs)

Description copied from interface: Twitter.IHttpClient

Set the timeout for a single get/post request. This is an optional method - implementations can ignore it!

Specified by:

setTimeout in interface Twitter.IHttpClient

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object