[Chapter 28] 28.9 java.net.HttpURLConnection (JDK 1.1)

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| Chapter 28 The java.net Package |

## 28.9 java.net.HttpURLConnection (JDK 1.1)

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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, and 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.

    public abstract class HttpURLConnection extends URLConnection {
        // Protected Constructor
                protected HttpURLConnection(URL u);
        // Response Code Constants
                public static final int HTTP_ACCEPTED, HTTP_BAD_GATEWAY, HTTP_BAD_METHOD;
                public static final int HTTP_BAD_REQUEST, HTTP_CLIENT_TIMEOUT, HTTP_CONFLICT;
                public static final int HTTP_CREATED, HTTP_ENTITY_TOO_LARGE, HTTP_FORBIDDEN;
                public static final int HTTP_GATEWAY_TIMEOUT, HTTP_GONE, HTTP_INTERNAL_ERROR;
                public static final int HTTP_LENGTH_REQUIRED, HTTP_MOVED_PERM, HTTP_MOVED_TEMP;
                public static final int HTTP_MULT_CHOICE, HTTP_NOT_ACCEPTABLE, HTTP_NOT_AUTHORITATIVE;
                public static final int HTTP_NOT_FOUND, HTTP_NOT_MODIFIED, HTTP_NO_CONTENT;
                public static final int HTTP_OK, HTTP_PARTIAL, HTTP_PAYMENT_REQUIRED;
                public static final int HTTP_PRECON_FAILED, HTTP_PROXY_AUTH, HTTP_REQ_TOO_LONG;
                public static final int HTTP_RESET, HTTP_SEE_OTHER, HTTP_SERVER_ERROR;
                public static final int HTTP_UNAUTHORIZED, HTTP_UNAVAILABLE, HTTP_UNSUPPORTED_TYPE;
                public static final int HTTP_USE_PROXY, HTTP_VERSION;
        // Protected Instance Variables
                protected String method;
                protected int responseCode;
                protected String responseMessage;
        // Class Methods
                public static boolean getFollowRedirects();
                public static void setFollowRedirects(boolean set);
        // Public Instance Methods
                public abstract void disconnect();
                public String getRequestMethod();
                public int getResponseCode() throws IOException;
                public String getResponseMessage() throws IOException;
                public void setRequestMethod(String method) throws ProtocolException;
                public abstract boolean usingProxy();
    }

### Hierarchy:

Object->URLConnection->HttpURLConnection

java.net.FileNameMap (JDK 1.1) |  | java.net.InetAddress (JDK 1.0)