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/*
* Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package java.net;
import java.io.InputStream;
import java.io.IOException;
import java.security.Permission;
import java.util.Date;
// Android-changed: top-level documentation substantially changed/rewritten.
/**
* A URLConnection with support for HTTP-specific features. See
* the spec for
* details.
*
*
*
Uses of this class follow a pattern:
*
* - Obtain a new {@code HttpURLConnection} by calling {@link
* URL#openConnection() URL.openConnection()} and casting the result to
* {@code HttpURLConnection}.
*
- Prepare the request. The primary property of a request is its URI.
* Request headers may also include metadata such as credentials, preferred
* content types, and session cookies.
*
- Optionally upload a request body. Instances must be configured with
* {@link #setDoOutput(boolean) setDoOutput(true)} if they include a
* request body. Transmit data by writing to the stream returned by {@link
* #getOutputStream()}.
*
- Read the response. Response headers typically include metadata such as
* the response body's content type and length, modified dates and session
* cookies. The response body may be read from the stream returned by {@link
* #getInputStream()}. If the response has no body, that method returns an
* empty stream.
*
- Disconnect. Once the response body has been read, the {@code
* HttpURLConnection} should be closed by calling {@link #disconnect()}.
* Disconnecting releases the resources held by a connection so they may
* be closed or reused.
*
*
* For example, to retrieve the webpage at {@code http://www.android.com/}:
*
{@code
* URL url = new URL("http://www.android.com/");
* HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
* try {
* InputStream in = new BufferedInputStream(urlConnection.getInputStream());
* readStream(in);
* } finally {
* urlConnection.disconnect();
* }
* }
*
* Secure Communication with HTTPS
* Calling {@link URL#openConnection()} on a URL with the "https"
* scheme will return an {@code HttpsURLConnection}, which allows for
* overriding the default {@link javax.net.ssl.HostnameVerifier
* HostnameVerifier} and {@link javax.net.ssl.SSLSocketFactory
* SSLSocketFactory}. An application-supplied {@code SSLSocketFactory}
* created from an {@link javax.net.ssl.SSLContext SSLContext} can
* provide a custom {@link javax.net.ssl.X509TrustManager
* X509TrustManager} for verifying certificate chains and a custom
* {@link javax.net.ssl.X509KeyManager X509KeyManager} for supplying
* client certificates. See {@link javax.net.ssl.HttpsURLConnection
* HttpsURLConnection} for more details.
*
* Response Handling
* {@code HttpURLConnection} will follow up to five HTTP redirects. It will
* follow redirects from one origin server to another. This implementation
* doesn't follow redirects from HTTPS to HTTP or vice versa.
*
* If the HTTP response indicates that an error occurred, {@link
* #getInputStream()} will throw an {@link IOException}. Use {@link
* #getErrorStream()} to read the error response. The headers can be read in
* the normal way using {@link #getHeaderFields()},
*
*
Posting Content
* To upload data to a web server, configure the connection for output using
* {@link #setDoOutput(boolean) setDoOutput(true)}.
*
* For best performance, you should call either {@link
* #setFixedLengthStreamingMode(int)} when the body length is known in advance,
* or {@link #setChunkedStreamingMode(int)} when it is not. Otherwise {@code
* HttpURLConnection} will be forced to buffer the complete request body in
* memory before it is transmitted, wasting (and possibly exhausting) heap and
* increasing latency.
*
*
For example, to perform an upload:
{@code
* HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
* try {
* urlConnection.setDoOutput(true);
* urlConnection.setChunkedStreamingMode(0);
*
* OutputStream out = new BufferedOutputStream(urlConnection.getOutputStream());
* writeStream(out);
*
* InputStream in = new BufferedInputStream(urlConnection.getInputStream());
* readStream(in);
* } finally {
* urlConnection.disconnect();
* }
* }
*
* Performance
* The input and output streams returned by this class are not
* buffered. Most callers should wrap the returned streams with {@link
* java.io.BufferedInputStream BufferedInputStream} or {@link
* java.io.BufferedOutputStream BufferedOutputStream}. Callers that do only bulk
* reads or writes may omit buffering.
*
* When transferring large amounts of data to or from a server, use streams
* to limit how much data is in memory at once. Unless you need the entire
* body to be in memory at once, process it as a stream (rather than storing
* the complete body as a single byte array or string).
*
*
To reduce latency, this class may reuse the same underlying {@code Socket}
* for multiple request/response pairs. As a result, HTTP connections may be
* held open longer than necessary. Calls to {@link #disconnect()} may return
* the socket to a pool of connected sockets.
*
*
By default, this implementation of {@code HttpURLConnection} requests that
* servers use gzip compression and it automatically decompresses the data for
* callers of {@link #getInputStream()}. The Content-Encoding and Content-Length
* response headers are cleared in this case. Gzip compression can be disabled by
* setting the acceptable encodings in the request header:
{@code
* urlConnection.setRequestProperty("Accept-Encoding", "identity");
* }
*
* Setting the Accept-Encoding request header explicitly disables automatic
* decompression and leaves the response headers intact; callers must handle
* decompression as needed, according to the Content-Encoding header of the
* response.
*
*
{@link #getContentLength()} returns the number of bytes transmitted and
* cannot be used to predict how many bytes can be read from
* {@link #getInputStream()} for compressed streams. Instead, read that stream
* until it is exhausted, i.e. when {@link InputStream#read} returns -1.
*
*
Handling Network Sign-On
* Some Wi-Fi networks block Internet access until the user clicks through a
* sign-on page. Such sign-on pages are typically presented by using HTTP
* redirects. You can use {@link #getURL()} to test if your connection has been
* unexpectedly redirected. This check is not valid until after
* the response headers have been received, which you can trigger by calling
* {@link #getHeaderFields()} or {@link #getInputStream()}. For example, to
* check that a response was not redirected to an unexpected host:
* {@code
* HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
* try {
* InputStream in = new BufferedInputStream(urlConnection.getInputStream());
* if (!url.getHost().equals(urlConnection.getURL().getHost())) {
* // we were redirected! Kick the user out to the browser to sign on?
* }
* ...
* } finally {
* urlConnection.disconnect();
* }
* }
*
* HTTP Authentication
* {@code HttpURLConnection} supports HTTP basic authentication. Use
* {@link Authenticator} to set the VM-wide authentication handler:
* {@code
* Authenticator.setDefault(new Authenticator() {
* protected PasswordAuthentication getPasswordAuthentication() {
* return new PasswordAuthentication(username, password.toCharArray());
* }
* });
* }
* Unless paired with HTTPS, this is not a secure mechanism for
* user authentication. In particular, the username, password, request and
* response are all transmitted over the network without encryption.
*
* Sessions with Cookies
* To establish and maintain a potentially long-lived session between client
* and server, {@code HttpURLConnection} includes an extensible cookie manager.
* Enable VM-wide cookie management using {@link CookieHandler} and {@link
* CookieManager}: {@code
* CookieManager cookieManager = new CookieManager();
* CookieHandler.setDefault(cookieManager);
* }
* By default, {@code CookieManager} accepts cookies from the origin
* server only. Two other policies are included: {@link
* CookiePolicy#ACCEPT_ALL} and {@link CookiePolicy#ACCEPT_NONE}. Implement
* {@link CookiePolicy} to define a custom policy.
*
* The default {@code CookieManager} keeps all accepted cookies in memory. It
* will forget these cookies when the VM exits. Implement {@link CookieStore} to
* define a custom cookie store.
*
*
In addition to the cookies set by HTTP responses, you may set cookies
* programmatically. To be included in HTTP request headers, cookies must have
* the domain and path properties set.
*
*
By default, new instances of {@code HttpCookie} work only with servers
* that support RFC 2965
* cookies. Many web servers support only the older specification, RFC 2109. For compatibility
* with the most web servers, set the cookie version to 0.
*
*
For example, to receive {@code www.twitter.com} in French:
{@code
* HttpCookie cookie = new HttpCookie("lang", "fr");
* cookie.setDomain("twitter.com");
* cookie.setPath("/");
* cookie.setVersion(0);
* cookieManager.getCookieStore().add(new URI("http://twitter.com/"), cookie);
* }
*
* HTTP Methods
* {@code HttpURLConnection} uses the {@code GET} method by default. It will
* use {@code POST} if {@link #setDoOutput setDoOutput(true)} has been called.
* Other HTTP methods ({@code OPTIONS}, {@code HEAD}, {@code PUT}, {@code
* DELETE} and {@code TRACE}) can be used with {@link #setRequestMethod}.
*
*
Proxies
* By default, this class will connect directly to the origin
* server. It can also connect via an {@link Proxy.Type#HTTP HTTP} or {@link
* Proxy.Type#SOCKS SOCKS} proxy. To use a proxy, use {@link
* URL#openConnection(Proxy) URL.openConnection(Proxy)} when creating the
* connection.
*
* IPv6 Support
* This class includes transparent support for IPv6. For hosts with both IPv4
* and IPv6 addresses, it will attempt to connect to each of a host's addresses
* until a connection is established.
*
*
Response Caching
* Android 4.0 (Ice Cream Sandwich, API level 15) includes a response cache. See
* {@code android.net.http.HttpResponseCache} for instructions on enabling HTTP
* caching in your application.
*
* Avoiding Bugs In Earlier Releases
* Prior to Android 2.2 (Froyo), this class had some frustrating bugs. In
* particular, calling {@code close()} on a readable {@code InputStream} could
* poison the
* connection pool. Work around this by disabling connection pooling:
* {@code
* private void disableConnectionReuseIfNecessary() {
* // Work around pre-Froyo bugs in HTTP connection reuse.
* if (Integer.parseInt(Build.VERSION.SDK) < Build.VERSION_CODES.FROYO) {
* System.setProperty("http.keepAlive", "false");
* }
* }}
*
* Each instance of {@code HttpURLConnection} may be used for one
* request/response pair. Instances of this class are not thread safe.
*
* @see java.net.HttpURLConnection#disconnect()
* @since JDK1.1
*/
abstract public class HttpURLConnection extends URLConnection {
/* instance variables */
/**
* The HTTP method (GET,POST,PUT,etc.).
*/
protected String method = "GET";
/**
* The chunk-length when using chunked encoding streaming mode for output.
* A value of {@code -1} means chunked encoding is disabled for output.
* @since 1.5
*/
protected int chunkLength = -1;
/**
* The fixed content-length when using fixed-length streaming mode.
* A value of {@code -1} means fixed-length streaming mode is disabled
* for output.
*
*
NOTE: {@link #fixedContentLengthLong} is recommended instead
* of this field, as it allows larger content lengths to be set.
*
* @since 1.5
*/
protected int fixedContentLength = -1;
/**
* The fixed content-length when using fixed-length streaming mode.
* A value of {@code -1} means fixed-length streaming mode is disabled
* for output.
*
* @since 1.7
*/
protected long fixedContentLengthLong = -1;
/**
* Returns the key for the {@code n}th header field.
* Some implementations may treat the {@code 0}th
* header field as special, i.e. as the status line returned by the HTTP
* server. In this case, {@link #getHeaderField(int) getHeaderField(0)} returns the status
* line, but {@code getHeaderFieldKey(0)} returns null.
*
* @param n an index, where {@code n >=0}.
* @return the key for the {@code n}th header field,
* or {@code null} if the key does not exist.
*/
public String getHeaderFieldKey (int n) {
return null;
}
/**
* This method is used to enable streaming of a HTTP request body
* without internal buffering, when the content length is known in
* advance.
*
* An exception will be thrown if the application
* attempts to write more data than the indicated
* content-length, or if the application closes the OutputStream
* before writing the indicated amount.
*
* When output streaming is enabled, authentication
* and redirection cannot be handled automatically.
* A HttpRetryException will be thrown when reading
* the response if authentication or redirection are required.
* This exception can be queried for the details of the error.
*
* This method must be called before the URLConnection is connected.
*
* NOTE: {@link #setFixedLengthStreamingMode(long)} is recommended
* instead of this method as it allows larger content lengths to be set.
*
* @param contentLength The number of bytes which will be written
* to the OutputStream.
*
* @throws IllegalStateException if URLConnection is already connected
* or if a different streaming mode is already enabled.
*
* @throws IllegalArgumentException if a content length less than
* zero is specified.
*
* @see #setChunkedStreamingMode(int)
* @since 1.5
*/
public void setFixedLengthStreamingMode (int contentLength) {
if (connected) {
throw new IllegalStateException ("Already connected");
}
if (chunkLength != -1) {
throw new IllegalStateException ("Chunked encoding streaming mode set");
}
if (contentLength < 0) {
throw new IllegalArgumentException ("invalid content length");
}
fixedContentLength = contentLength;
}
/**
* This method is used to enable streaming of a HTTP request body
* without internal buffering, when the content length is known in
* advance.
*
*
An exception will be thrown if the application attempts to write
* more data than the indicated content-length, or if the application
* closes the OutputStream before writing the indicated amount.
*
*
When output streaming is enabled, authentication and redirection
* cannot be handled automatically. A {@linkplain HttpRetryException} will
* be thrown when reading the response if authentication or redirection
* are required. This exception can be queried for the details of the
* error.
*
*
This method must be called before the URLConnection is connected.
*
*
The content length set by invoking this method takes precedence
* over any value set by {@link #setFixedLengthStreamingMode(int)}.
*
* @param contentLength
* The number of bytes which will be written to the OutputStream.
*
* @throws IllegalStateException
* if URLConnection is already connected or if a different
* streaming mode is already enabled.
*
* @throws IllegalArgumentException
* if a content length less than zero is specified.
*
* @since 1.7
*/
public void setFixedLengthStreamingMode(long contentLength) {
if (connected) {
throw new IllegalStateException("Already connected");
}
if (chunkLength != -1) {
throw new IllegalStateException(
"Chunked encoding streaming mode set");
}
if (contentLength < 0) {
throw new IllegalArgumentException("invalid content length");
}
fixedContentLengthLong = contentLength;
}
/* Default chunk size (including chunk header) if not specified;
* we want to keep this in sync with the one defined in
* sun.net.www.http.ChunkedOutputStream
*/
private static final int DEFAULT_CHUNK_SIZE = 4096;
/**
* This method is used to enable streaming of a HTTP request body
* without internal buffering, when the content length is not
* known in advance. In this mode, chunked transfer encoding
* is used to send the request body. Note, not all HTTP servers
* support this mode.
*
* When output streaming is enabled, authentication
* and redirection cannot be handled automatically.
* A HttpRetryException will be thrown when reading
* the response if authentication or redirection are required.
* This exception can be queried for the details of the error.
*
* This method must be called before the URLConnection is connected.
*
* @param chunklen The number of bytes to write in each chunk.
* If chunklen is less than or equal to zero, a default
* value will be used.
*
* @throws IllegalStateException if URLConnection is already connected
* or if a different streaming mode is already enabled.
*
* @see #setFixedLengthStreamingMode(int)
* @since 1.5
*/
public void setChunkedStreamingMode (int chunklen) {
if (connected) {
throw new IllegalStateException ("Can't set streaming mode: already connected");
}
if (fixedContentLength != -1 || fixedContentLengthLong != -1) {
throw new IllegalStateException ("Fixed length streaming mode set");
}
chunkLength = chunklen <=0? DEFAULT_CHUNK_SIZE : chunklen;
}
/**
* Returns the value for the {@code n}th header field.
* Some implementations may treat the {@code 0}th
* header field as special, i.e. as the status line returned by the HTTP
* server.
*
* This method can be used in conjunction with the
* {@link #getHeaderFieldKey getHeaderFieldKey} method to iterate through all
* the headers in the message.
*
* @param n an index, where {@code n>=0}.
* @return the value of the {@code n}th header field,
* or {@code null} if the value does not exist.
* @see java.net.HttpURLConnection#getHeaderFieldKey(int)
*/
public String getHeaderField(int n) {
return null;
}
/**
* An {@code int} representing the three digit HTTP Status-Code.
*
* - 1xx: Informational
*
- 2xx: Success
*
- 3xx: Redirection
*
- 4xx: Client Error
*
- 5xx: Server Error
*
*/
protected int responseCode = -1;
/**
* The HTTP response message.
*/
protected String responseMessage = null;
/* static variables */
/* do we automatically follow redirects? The default is true. */
private static boolean followRedirects = true;
/**
* If {@code true}, the protocol will automatically follow redirects.
* If {@code false}, the protocol will not automatically follow
* redirects.
*
* This field is set by the {@code setInstanceFollowRedirects}
* method. Its value is returned by the {@code getInstanceFollowRedirects}
* method.
*
* Its default value is based on the value of the static followRedirects
* at HttpURLConnection construction time.
*
* @see java.net.HttpURLConnection#setInstanceFollowRedirects(boolean)
* @see java.net.HttpURLConnection#getInstanceFollowRedirects()
* @see java.net.HttpURLConnection#setFollowRedirects(boolean)
*/
protected boolean instanceFollowRedirects = followRedirects;
/* valid HTTP methods */
private static final String[] methods = {
"GET", "POST", "HEAD", "OPTIONS", "PUT", "DELETE", "TRACE"
};
/**
* Constructor for the HttpURLConnection.
* @param u the URL
*/
protected HttpURLConnection (URL u) {
super(u);
}
/**
* Sets whether HTTP redirects (requests with response code 3xx) should
* be automatically followed by this class. True by default. Applets
* cannot change this variable.
*
* If there is a security manager, this method first calls
* the security manager's {@code checkSetFactory} method
* to ensure the operation is allowed.
* This could result in a SecurityException.
*
* @param set a {@code boolean} indicating whether or not
* to follow HTTP redirects.
* @exception SecurityException if a security manager exists and its
* {@code checkSetFactory} method doesn't
* allow the operation.
* @see SecurityManager#checkSetFactory
* @see #getFollowRedirects()
*/
public static void setFollowRedirects(boolean set) {
SecurityManager sec = System.getSecurityManager();
if (sec != null) {
// seems to be the best check here...
sec.checkSetFactory();
}
followRedirects = set;
}
/**
* Returns a {@code boolean} indicating
* whether or not HTTP redirects (3xx) should
* be automatically followed.
*
* @return {@code true} if HTTP redirects should
* be automatically followed, {@code false} if not.
* @see #setFollowRedirects(boolean)
*/
public static boolean getFollowRedirects() {
return followRedirects;
}
/**
* Sets whether HTTP redirects (requests with response code 3xx) should
* be automatically followed by this {@code HttpURLConnection}
* instance.
*
* The default value comes from followRedirects, which defaults to
* true.
*
* @param followRedirects a {@code boolean} indicating
* whether or not to follow HTTP redirects.
*
* @see java.net.HttpURLConnection#instanceFollowRedirects
* @see #getInstanceFollowRedirects
* @since 1.3
*/
public void setInstanceFollowRedirects(boolean followRedirects) {
instanceFollowRedirects = followRedirects;
}
/**
* Returns the value of this {@code HttpURLConnection}'s
* {@code instanceFollowRedirects} field.
*
* @return the value of this {@code HttpURLConnection}'s
* {@code instanceFollowRedirects} field.
* @see java.net.HttpURLConnection#instanceFollowRedirects
* @see #setInstanceFollowRedirects(boolean)
* @since 1.3
*/
public boolean getInstanceFollowRedirects() {
return instanceFollowRedirects;
}
/**
* Set the method for the URL request, one of:
*
* - GET
*
- POST
*
- HEAD
*
- OPTIONS
*
- PUT
*
- DELETE
*
- TRACE
*
are legal, subject to protocol restrictions. The default
* method is GET.
*
* @param method the HTTP method
* @exception ProtocolException if the method cannot be reset or if
* the requested method isn't valid for HTTP.
* @exception SecurityException if a security manager is set and the
* method is "TRACE", but the "allowHttpTrace"
* NetPermission is not granted.
* @see #getRequestMethod()
*/
public void setRequestMethod(String method) throws ProtocolException {
if (connected) {
throw new ProtocolException("Can't reset method: already connected");
}
// This restriction will prevent people from using this class to
// experiment w/ new HTTP methods using java. But it should
// be placed for security - the request String could be
// arbitrarily long.
for (int i = 0; i < methods.length; i++) {
if (methods[i].equals(method)) {
if (method.equals("TRACE")) {
SecurityManager s = System.getSecurityManager();
if (s != null) {
s.checkPermission(new NetPermission("allowHttpTrace"));
}
}
this.method = method;
return;
}
}
throw new ProtocolException("Invalid HTTP method: " + method);
}
/**
* Get the request method.
* @return the HTTP request method
* @see #setRequestMethod(java.lang.String)
*/
public String getRequestMethod() {
return method;
}
/**
* Gets the status code from an HTTP response message.
* For example, in the case of the following status lines:
*
* HTTP/1.0 200 OK
* HTTP/1.0 401 Unauthorized
*
* It will return 200 and 401 respectively.
* Returns -1 if no code can be discerned
* from the response (i.e., the response is not valid HTTP).
* @throws IOException if an error occurred connecting to the server.
* @return the HTTP Status-Code, or -1
*/
public int getResponseCode() throws IOException {
/*
* We're got the response code already
*/
if (responseCode != -1) {
return responseCode;
}
/*
* Ensure that we have connected to the server. Record
* exception as we need to re-throw it if there isn't
* a status line.
*/
Exception exc = null;
try {
getInputStream();
} catch (Exception e) {
exc = e;
}
/*
* If we can't a status-line then re-throw any exception
* that getInputStream threw.
*/
String statusLine = getHeaderField(0);
if (statusLine == null) {
if (exc != null) {
if (exc instanceof RuntimeException)
throw (RuntimeException)exc;
else
throw (IOException)exc;
}
return -1;
}
/*
* Examine the status-line - should be formatted as per
* section 6.1 of RFC 2616 :-
*
* Status-Line = HTTP-Version SP Status-Code SP Reason-Phrase
*
* If status line can't be parsed return -1.
*/
if (statusLine.startsWith("HTTP/1.")) {
int codePos = statusLine.indexOf(' ');
if (codePos > 0) {
int phrasePos = statusLine.indexOf(' ', codePos+1);
if (phrasePos > 0 && phrasePos < statusLine.length()) {
responseMessage = statusLine.substring(phrasePos+1);
}
// deviation from RFC 2616 - don't reject status line
// if SP Reason-Phrase is not included.
if (phrasePos < 0)
phrasePos = statusLine.length();
try {
responseCode = Integer.parseInt
(statusLine.substring(codePos+1, phrasePos));
return responseCode;
} catch (NumberFormatException e) { }
}
}
return -1;
}
/**
* Gets the HTTP response message, if any, returned along with the
* response code from a server. From responses like:
*
* HTTP/1.0 200 OK
* HTTP/1.0 404 Not Found
*
* Extracts the Strings "OK" and "Not Found" respectively.
* Returns null if none could be discerned from the responses
* (the result was not valid HTTP).
* @throws IOException if an error occurred connecting to the server.
* @return the HTTP response message, or {@code null}
*/
public String getResponseMessage() throws IOException {
getResponseCode();
return responseMessage;
}
@SuppressWarnings("deprecation")
public long getHeaderFieldDate(String name, long Default) {
String dateString = getHeaderField(name);
try {
if (dateString.indexOf("GMT") == -1) {
dateString = dateString+" GMT";
}
return Date.parse(dateString);
} catch (Exception e) {
}
return Default;
}
/**
* Indicates that other requests to the server
* are unlikely in the near future. Calling disconnect()
* should not imply that this HttpURLConnection
* instance can be reused for other requests.
*/
public abstract void disconnect();
/**
* Indicates if the connection is going through a proxy.
* @return a boolean indicating if the connection is
* using a proxy.
*/
public abstract boolean usingProxy();
/**
* Returns a {@link SocketPermission} object representing the
* permission necessary to connect to the destination host and port.
*
* @exception IOException if an error occurs while computing
* the permission.
*
* @return a {@code SocketPermission} object representing the
* permission necessary to connect to the destination
* host and port.
*/
public Permission getPermission() throws IOException {
int port = url.getPort();
port = port < 0 ? 80 : port;
String host = url.getHost() + ":" + port;
Permission permission = new SocketPermission(host, "connect");
return permission;
}
/**
* Returns the error stream if the connection failed
* but the server sent useful data nonetheless. The
* typical example is when an HTTP server responds
* with a 404, which will cause a FileNotFoundException
* to be thrown in connect, but the server sent an HTML
* help page with suggestions as to what to do.
*
* This method will not cause a connection to be initiated. If
* the connection was not connected, or if the server did not have
* an error while connecting or if the server had an error but
* no error data was sent, this method will return null. This is
* the default.
*
* @return an error stream if any, null if there have been no
* errors, the connection is not connected or the server sent no
* useful data.
*/
public InputStream getErrorStream() {
return null;
}
/**
* The response codes for HTTP, as of version 1.1.
*/
// REMIND: do we want all these??
// Others not here that we do want??
/* 2XX: generally "OK" */
/**
* HTTP Status-Code 200: OK.
*/
public static final int HTTP_OK = 200;
/**
* HTTP Status-Code 201: Created.
*/
public static final int HTTP_CREATED = 201;
/**
* HTTP Status-Code 202: Accepted.
*/
public static final int HTTP_ACCEPTED = 202;
/**
* HTTP Status-Code 203: Non-Authoritative Information.
*/
public static final int HTTP_NOT_AUTHORITATIVE = 203;
/**
* HTTP Status-Code 204: No Content.
*/
public static final int HTTP_NO_CONTENT = 204;
/**
* HTTP Status-Code 205: Reset Content.
*/
public static final int HTTP_RESET = 205;
/**
* HTTP Status-Code 206: Partial Content.
*/
public static final int HTTP_PARTIAL = 206;
/* 3XX: relocation/redirect */
/**
* HTTP Status-Code 300: Multiple Choices.
*/
public static final int HTTP_MULT_CHOICE = 300;
/**
* HTTP Status-Code 301: Moved Permanently.
*/
public static final int HTTP_MOVED_PERM = 301;
/**
* HTTP Status-Code 302: Temporary Redirect.
*/
public static final int HTTP_MOVED_TEMP = 302;
/**
* HTTP Status-Code 303: See Other.
*/
public static final int HTTP_SEE_OTHER = 303;
/**
* HTTP Status-Code 304: Not Modified.
*/
public static final int HTTP_NOT_MODIFIED = 304;
/**
* HTTP Status-Code 305: Use Proxy.
*/
public static final int HTTP_USE_PROXY = 305;
/* 4XX: client error */
/**
* HTTP Status-Code 400: Bad Request.
*/
public static final int HTTP_BAD_REQUEST = 400;
/**
* HTTP Status-Code 401: Unauthorized.
*/
public static final int HTTP_UNAUTHORIZED = 401;
/**
* HTTP Status-Code 402: Payment Required.
*/
public static final int HTTP_PAYMENT_REQUIRED = 402;
/**
* HTTP Status-Code 403: Forbidden.
*/
public static final int HTTP_FORBIDDEN = 403;
/**
* HTTP Status-Code 404: Not Found.
*/
public static final int HTTP_NOT_FOUND = 404;
/**
* HTTP Status-Code 405: Method Not Allowed.
*/
public static final int HTTP_BAD_METHOD = 405;
/**
* HTTP Status-Code 406: Not Acceptable.
*/
public static final int HTTP_NOT_ACCEPTABLE = 406;
/**
* HTTP Status-Code 407: Proxy Authentication Required.
*/
public static final int HTTP_PROXY_AUTH = 407;
/**
* HTTP Status-Code 408: Request Time-Out.
*/
public static final int HTTP_CLIENT_TIMEOUT = 408;
/**
* HTTP Status-Code 409: Conflict.
*/
public static final int HTTP_CONFLICT = 409;
/**
* HTTP Status-Code 410: Gone.
*/
public static final int HTTP_GONE = 410;
/**
* HTTP Status-Code 411: Length Required.
*/
public static final int HTTP_LENGTH_REQUIRED = 411;
/**
* HTTP Status-Code 412: Precondition Failed.
*/
public static final int HTTP_PRECON_FAILED = 412;
/**
* HTTP Status-Code 413: Request Entity Too Large.
*/
public static final int HTTP_ENTITY_TOO_LARGE = 413;
/**
* HTTP Status-Code 414: Request-URI Too Large.
*/
public static final int HTTP_REQ_TOO_LONG = 414;
/**
* HTTP Status-Code 415: Unsupported Media Type.
*/
public static final int HTTP_UNSUPPORTED_TYPE = 415;
/* 5XX: server error */
/**
* HTTP Status-Code 500: Internal Server Error.
* @deprecated it is misplaced and shouldn't have existed.
*/
@Deprecated
public static final int HTTP_SERVER_ERROR = 500;
/**
* HTTP Status-Code 500: Internal Server Error.
*/
public static final int HTTP_INTERNAL_ERROR = 500;
/**
* HTTP Status-Code 501: Not Implemented.
*/
public static final int HTTP_NOT_IMPLEMENTED = 501;
/**
* HTTP Status-Code 502: Bad Gateway.
*/
public static final int HTTP_BAD_GATEWAY = 502;
/**
* HTTP Status-Code 503: Service Unavailable.
*/
public static final int HTTP_UNAVAILABLE = 503;
/**
* HTTP Status-Code 504: Gateway Timeout.
*/
public static final int HTTP_GATEWAY_TIMEOUT = 504;
/**
* HTTP Status-Code 505: HTTP Version Not Supported.
*/
public static final int HTTP_VERSION = 505;
}