Java in a Nutshell, 5th Edition [Electronic resources] نسخه متنی

This class is a specialization of
URLConnection. An instance of this class is
returned when the openConnection( ) method is
called for a URL object that uses the HTTP
protocol. The many
constants
defined by this class are the status codes returned by HTTP servers.
setRequestMethod(
) specifies what kind of HTTP request is made.
The contents of this request must be sent through the
OutputStream returned by the
getOutputStream(
) method of the superclass. Once an HTTP
request has been sent, getresponseCode(
) returns the HTTP server's
response code as an integer, and geTResponseMessage(
) returns the server's
response message. The disconnect(
)
method closes the connection. The static setFollowRedirects(
) specifies whether URL connections that use the HTTP
protocol should automatically follow redirect responses sent by HTTP
servers. In order to successfully use this class, you need to
understand the details of the HTTP protocol.

Figure 12-5. java.net.HttpURLConnection

public abstract class

HttpURLConnection extends URLConnection {
// Protected Constructors
protected

HttpURLConnection (URL

u );
// Public Constants
public static final int

HTTP_ACCEPTED ; =202
public static final int

HTTP_BAD_GATEWAY ; =502
public static final int

HTTP_BAD_METHOD ; =405
public static final int

HTTP_BAD_REQUEST ; =400
public static final int

HTTP_CLIENT_TIMEOUT ; =408
public static final int

HTTP_CONFLICT ; =409
public static final int

HTTP_CREATED ; =201
public static final int

HTTP_ENTITY_TOO_LARGE ; =413
public static final int

HTTP_FORBIDDEN ; =403
public static final int

HTTP_GATEWAY_TIMEOUT ; =504
public static final int

HTTP_GONE ; =410
public static final int

HTTP_INTERNAL_ERROR ; =500
public static final int

HTTP_LENGTH_REQUIRED ; =411
public static final int

HTTP_MOVED_PERM ; =301
public static final int

HTTP_MOVED_TEMP ; =302
public static final int

HTTP_MULT_CHOICE ; =300
public static final int

HTTP_NO_CONTENT ; =204
public static final int

HTTP_NOT_ACCEPTABLE ; =406
public static final int

HTTP_NOT_AUTHORITATIVE ; =203
public static final int

HTTP_NOT_FOUND ; =404

1.3 public static final int

HTTP_NOT_IMPLEMENTED ; =501
public static final int

HTTP_NOT_MODIFIED ; =304
public static final int

HTTP_OK ; =200
public static final int

HTTP_PARTIAL ; =206
public static final int

HTTP_PAYMENT_REQUIRED ; =402
public static final int

HTTP_PRECON_FAILED ; =412
public static final int

HTTP_PROXY_AUTH ; =407
public static final int

HTTP_REQ_TOO_LONG ; =414
public static final int

HTTP_RESET ; =205
public static final int

HTTP_SEE_OTHER ; =303
public static final int

HTTP_UNAUTHORIZED ; =401
public static final int

HTTP_UNAVAILABLE ; =503
public static final int

HTTP_UNSUPPORTED_TYPE ; =415
public static final int

HTTP_USE_PROXY ; =305
public static final int

HTTP_VERSION ; =505
// Public Class Methods
public static boolean

getFollowRedirects ( );
public static void

setFollowRedirects (boolean

set );
// Public Instance Methods
public abstract void

disconnect ( );

1.2 public java.io.InputStream

getErrorStream ( ); constant

1.3 public boolean

getInstanceFollowRedirects ( );
public String

getRequestMethod ( );
public int

getResponseCode ( ) throws java.io.IOException;
public String

getResponseMessage ( ) throws java.io.IOException;

5.0 public void

setChunkedStreamingMode (int

chunklen );

5.0 public void

setFixedLengthStreamingMode (int

contentLength );

1.3 public void

setInstanceFollowRedirects (boolean

followRedirects );
public void

setRequestMethod (String

method ) throws ProtocolException;
public abstract boolean

usingProxy ( );
// Public Methods Overriding URLConnection

1.4 public String

getHeaderField (int

n ); constant

1.3 public long

getHeaderFieldDate (String

name , long

Default );

1.4 public String

getHeaderFieldKey (int

n ); constant

1.2 public java.security.Permission

getPermission ( )
throws java.io.IOException;
// Protected Instance Fields

5.0 protected int

chunkLength ;

5.0 protected int

fixedContentLength ;

1.3 protected boolean

instanceFollowRedirects ;
protected String

method ;
protected int

responseCode ;
protected String

responseMessage ;
// Deprecated Public Fields

# public static final int

HTTP_SERVER_ERROR ; =500
}

Subclasses

javax.net.ssl.HttpsURLConnection