J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package com.sun.net.httpserver; |
| 27 | |
| 28 | import java.io.*; |
| 29 | import java.nio.*; |
| 30 | import java.nio.channels.*; |
| 31 | import java.net.*; |
| 32 | import javax.net.ssl.*; |
| 33 | import java.util.*; |
| 34 | import sun.net.www.MessageHeader; |
| 35 | |
| 36 | /** |
| 37 | * This class encapsulates a HTTP request received and a |
| 38 | * response to be generated in one exchange. It provides methods |
| 39 | * for examining the request from the client, and for building and |
| 40 | * sending the response. |
| 41 | * <p> |
| 42 | * The typical life-cycle of a HttpExchange is shown in the sequence |
| 43 | * below. |
| 44 | * <ol><li>{@link #getRequestMethod()} to determine the command |
| 45 | * <li>{@link #getRequestHeaders()} to examine the request headers (if needed) |
| 46 | * <li>{@link #getRequestBody()} returns a {@link java.io.InputStream} for reading the request body. |
| 47 | * After reading the request body, the stream is close. |
| 48 | * <li>{@link #getResponseHeaders()} to set any response headers, except content-length |
| 49 | * <li>{@link #sendResponseHeaders(int,long)} to send the response headers. Must be called before |
| 50 | * next step. |
| 51 | * <li>{@link #getResponseBody()} to get a {@link java.io.OutputStream} to send the response body. |
| 52 | * When the response body has been written, the stream must be closed to terminate the exchange. |
| 53 | * </ol> |
| 54 | * <b>Terminating exchanges</b> |
| 55 | * <br> |
| 56 | * Exchanges are terminated when both the request InputStream and response OutputStream are closed. |
| 57 | * Closing the OutputStream, implicitly closes the InputStream (if it is not already closed). |
| 58 | * However, it is recommended |
| 59 | * to consume all the data from the InputStream before closing it. |
| 60 | * The convenience method {@link #close()} does all of these tasks. |
| 61 | * Closing an exchange without consuming all of the request body is not an error |
| 62 | * but may make the underlying TCP connection unusable for following exchanges. |
| 63 | * The effect of failing to terminate an exchange is undefined, but will typically |
| 64 | * result in resources failing to be freed/reused. |
| 65 | * @since 1.6 |
| 66 | */ |
| 67 | |
| 68 | public abstract class HttpExchange { |
| 69 | |
| 70 | protected HttpExchange () { |
| 71 | } |
| 72 | |
| 73 | /** |
| 74 | * Returns an immutable Map containing the HTTP headers that were |
| 75 | * included with this request. The keys in this Map will be the header |
| 76 | * names, while the values will be a List of Strings containing each value |
| 77 | * that was included (either for a header that was listed several times, |
| 78 | * or one that accepts a comma-delimited list of values on a single line). |
| 79 | * In either of these cases, the values for the header name will be |
| 80 | * presented in the order that they were included in the request. |
| 81 | * <p> |
| 82 | * The keys in Map are case-insensitive. |
| 83 | * @return a read-only Map which can be used to access request headers |
| 84 | */ |
| 85 | public abstract Headers getRequestHeaders () ; |
| 86 | |
| 87 | /** |
| 88 | * Returns a mutable Map into which the HTTP response headers can be stored |
| 89 | * and which will be transmitted as part of this response. The keys in the |
| 90 | * Map will be the header names, while the values must be a List of Strings |
| 91 | * containing each value that should be included multiple times |
| 92 | * (in the order that they should be included). |
| 93 | * <p> |
| 94 | * The keys in Map are case-insensitive. |
| 95 | * @return a writable Map which can be used to set response headers. |
| 96 | */ |
| 97 | public abstract Headers getResponseHeaders () ; |
| 98 | |
| 99 | /** |
| 100 | * Get the request URI |
| 101 | * |
| 102 | * @return the request URI |
| 103 | */ |
| 104 | public abstract URI getRequestURI () ; |
| 105 | |
| 106 | /** |
| 107 | * Get the request method |
| 108 | * @return the request method |
| 109 | */ |
| 110 | public abstract String getRequestMethod (); |
| 111 | |
| 112 | /** |
| 113 | * Get the HttpContext for this exchange |
| 114 | * @return the HttpContext |
| 115 | */ |
| 116 | public abstract HttpContext getHttpContext (); |
| 117 | |
| 118 | /** |
| 119 | * Ends this exchange by doing the following in sequence:<p><ol> |
| 120 | * <li>close the request InputStream, if not already closed<p></li> |
| 121 | * <li>close the response OutputStream, if not already closed. </li> |
| 122 | * </ol> |
| 123 | */ |
| 124 | public abstract void close () ; |
| 125 | |
| 126 | /** |
| 127 | * returns a stream from which the request body can be read. |
| 128 | * Multiple calls to this method will return the same stream. |
| 129 | * It is recommended that applications should consume (read) all of the |
| 130 | * data from this stream before closing it. If a stream is closed |
| 131 | * before all data has been read, then the close() call will |
| 132 | * read and discard remaining data (up to an implementation specific |
| 133 | * number of bytes). |
| 134 | * @return the stream from which the request body can be read. |
| 135 | */ |
| 136 | public abstract InputStream getRequestBody () ; |
| 137 | |
| 138 | /** |
| 139 | * returns a stream to which the response body must be |
| 140 | * written. {@link #sendResponseHeaders(int,long)}) must be called prior to calling |
| 141 | * this method. Multiple calls to this method (for the same exchange) |
| 142 | * will return the same stream. In order to correctly terminate |
| 143 | * each exchange, the output stream must be closed, even if no |
| 144 | * response body is being sent. |
| 145 | * <p> |
| 146 | * Closing this stream implicitly |
| 147 | * closes the InputStream returned from {@link #getRequestBody()} |
| 148 | * (if it is not already closed). |
| 149 | * <P> |
| 150 | * If the call to sendResponseHeaders() specified a fixed response |
| 151 | * body length, then the exact number of bytes specified in that |
| 152 | * call must be written to this stream. If too many bytes are written, |
| 153 | * then write() will throw an IOException. If too few bytes are written |
| 154 | * then the stream close() will throw an IOException. In both cases, |
| 155 | * the exchange is aborted and the underlying TCP connection closed. |
| 156 | * @return the stream to which the response body is written |
| 157 | */ |
| 158 | public abstract OutputStream getResponseBody () ; |
| 159 | |
| 160 | |
| 161 | /** |
| 162 | * Starts sending the response back to the client using the current set of response headers |
| 163 | * and the numeric response code as specified in this method. The response body length is also specified |
| 164 | * as follows. If the response length parameter is greater than zero, this specifies an exact |
| 165 | * number of bytes to send and the application must send that exact amount of data. |
| 166 | * If the response length parameter is <code>zero</code>, then chunked transfer encoding is |
| 167 | * used and an arbitrary amount of data may be sent. The application terminates the |
| 168 | * response body by closing the OutputStream. If response length has the value <code>-1</code> |
| 169 | * then no response body is being sent. |
| 170 | * <p> |
| 171 | * If the content-length response header has not already been set then |
| 172 | * this is set to the apropriate value depending on the response length parameter. |
| 173 | * <p> |
| 174 | * This method must be called prior to calling {@link #getResponseBody()}. |
| 175 | * @param rCode the response code to send |
| 176 | * @param responseLength if > 0, specifies a fixed response body length |
| 177 | * and that exact number of bytes must be written |
| 178 | * to the stream acquired from getResponseBody(), or else |
| 179 | * if equal to 0, then chunked encoding is used, |
| 180 | * and an arbitrary number of bytes may be written. |
| 181 | * if <= -1, then no response body length is specified and |
| 182 | * no response body may be written. |
| 183 | * @see HttpExchange#getResponseBody() |
| 184 | */ |
| 185 | public abstract void sendResponseHeaders (int rCode, long responseLength) throws IOException ; |
| 186 | |
| 187 | /** |
| 188 | * Returns the address of the remote entity invoking this request |
| 189 | * @return the InetSocketAddress of the caller |
| 190 | */ |
| 191 | public abstract InetSocketAddress getRemoteAddress (); |
| 192 | |
| 193 | /** |
| 194 | * Returns the response code, if it has already been set |
| 195 | * @return the response code, if available. <code>-1</code> if not available yet. |
| 196 | */ |
| 197 | public abstract int getResponseCode (); |
| 198 | |
| 199 | /** |
| 200 | * Returns the local address on which the request was received |
| 201 | * @return the InetSocketAddress of the local interface |
| 202 | */ |
| 203 | public abstract InetSocketAddress getLocalAddress (); |
| 204 | |
| 205 | /** |
| 206 | * Returns the protocol string from the request in the form |
| 207 | * <i>protocol/majorVersion.minorVersion</i>. For example, |
| 208 | * "HTTP/1.1" |
| 209 | * @return the protocol string from the request |
| 210 | */ |
| 211 | public abstract String getProtocol (); |
| 212 | |
| 213 | /** |
| 214 | * Filter modules may store arbitrary objects with HttpExchange |
| 215 | * instances as an out-of-band communication mechanism. Other Filters |
| 216 | * or the exchange handler may then access these objects. |
| 217 | * <p> |
| 218 | * Each Filter class will document the attributes which they make |
| 219 | * available. |
| 220 | * @param name the name of the attribute to retrieve |
| 221 | * @return the attribute object, or null if it does not exist |
| 222 | * @throws NullPointerException if name is <code>null</code> |
| 223 | */ |
| 224 | public abstract Object getAttribute (String name) ; |
| 225 | |
| 226 | /** |
| 227 | * Filter modules may store arbitrary objects with HttpExchange |
| 228 | * instances as an out-of-band communication mechanism. Other Filters |
| 229 | * or the exchange handler may then access these objects. |
| 230 | * <p> |
| 231 | * Each Filter class will document the attributes which they make |
| 232 | * available. |
| 233 | * @param name the name to associate with the attribute value |
| 234 | * @param value the object to store as the attribute value. <code>null</code> |
| 235 | * value is permitted. |
| 236 | * @throws NullPointerException if name is <code>null</code> |
| 237 | */ |
| 238 | public abstract void setAttribute (String name, Object value) ; |
| 239 | |
| 240 | /** |
| 241 | * Used by Filters to wrap either (or both) of this exchange's InputStream |
| 242 | * and OutputStream, with the given filtered streams so |
| 243 | * that subsequent calls to {@link #getRequestBody()} will |
| 244 | * return the given {@link java.io.InputStream}, and calls to |
| 245 | * {@link #getResponseBody()} will return the given |
| 246 | * {@link java.io.OutputStream}. The streams provided to this |
| 247 | * call must wrap the original streams, and may be (but are not |
| 248 | * required to be) sub-classes of {@link java.io.FilterInputStream} |
| 249 | * and {@link java.io.FilterOutputStream}. |
| 250 | * @param i the filtered input stream to set as this object's inputstream, |
| 251 | * or <code>null</code> if no change. |
| 252 | * @param o the filtered output stream to set as this object's outputstream, |
| 253 | * or <code>null</code> if no change. |
| 254 | */ |
| 255 | public abstract void setStreams (InputStream i, OutputStream o); |
| 256 | |
| 257 | |
| 258 | /** |
| 259 | * If an authenticator is set on the HttpContext that owns this exchange, |
| 260 | * then this method will return the {@link HttpPrincipal} that represents |
| 261 | * the authenticated user for this HttpExchange. |
| 262 | * @return the HttpPrincipal, or <code>null</code> if no authenticator is set. |
| 263 | */ |
| 264 | public abstract HttpPrincipal getPrincipal (); |
| 265 | } |