Java tutorial
/* * Copyright 2015 The Netty Project * * The Netty Project licenses this file to you under the Apache License, * version 2.0 (the "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. */ package io.netty.handler.codec.http.cookie; import static io.netty.handler.codec.http.cookie.CookieUtil.add; import static io.netty.handler.codec.http.cookie.CookieUtil.addQuoted; import static io.netty.handler.codec.http.cookie.CookieUtil.stringBuilder; import static io.netty.handler.codec.http.cookie.CookieUtil.stripTrailingSeparator; import static io.netty.util.internal.ObjectUtil.checkNotNull; import io.netty.handler.codec.DateFormatter; import io.netty.handler.codec.http.HttpConstants; import io.netty.handler.codec.http.HttpResponse; import java.util.ArrayList; import java.util.Collection; import java.util.Collections; import java.util.Date; import java.util.HashMap; import java.util.Iterator; import java.util.List; import java.util.Map; /** * A <a href="http://tools.ietf.org/html/rfc6265">RFC6265</a> compliant cookie encoder to be used server side, * so some fields are sent (Version is typically ignored). * * As Netty's Cookie merges Expires and MaxAge into one single field, only Max-Age field is sent. * * Note that multiple cookies must be sent as separate "Set-Cookie" headers. * * <pre> * // Example * {@link HttpResponse} res = ...; * res.setHeader("Set-Cookie", {@link ServerCookieEncoder}.encode("JSESSIONID", "1234")); * </pre> * * @see ServerCookieDecoder */ public final class ServerCookieEncoder extends CookieEncoder { /** * Strict encoder that validates that name and value chars are in the valid scope * defined in RFC6265, and (for methods that accept multiple cookies) that only * one cookie is encoded with any given name. (If multiple cookies have the same * name, the last one is the one that is encoded.) */ public static final ServerCookieEncoder STRICT = new ServerCookieEncoder(true); /** * Lax instance that doesn't validate name and value, and that allows multiple * cookies with the same name. */ public static final ServerCookieEncoder LAX = new ServerCookieEncoder(false); private ServerCookieEncoder(boolean strict) { super(strict); } /** * Encodes the specified cookie name-value pair into a Set-Cookie header value. * * @param name the cookie name * @param value the cookie value * @return a single Set-Cookie header value */ public String encode(String name, String value) { return encode(new DefaultCookie(name, value)); } /** * Encodes the specified cookie into a Set-Cookie header value. * * @param cookie the cookie * @return a single Set-Cookie header value */ public String encode(Cookie cookie) { final String name = checkNotNull(cookie, "cookie").name(); final String value = cookie.value() != null ? cookie.value() : ""; validateCookie(name, value); StringBuilder buf = stringBuilder(); if (cookie.wrap()) { addQuoted(buf, name, value); } else { add(buf, name, value); } if (cookie.maxAge() != Long.MIN_VALUE) { add(buf, CookieHeaderNames.MAX_AGE, cookie.maxAge()); Date expires = new Date(cookie.maxAge() * 1000 + System.currentTimeMillis()); buf.append(CookieHeaderNames.EXPIRES); buf.append('='); DateFormatter.append(expires, buf); buf.append(';'); buf.append(HttpConstants.SP_CHAR); } if (cookie.path() != null) { add(buf, CookieHeaderNames.PATH, cookie.path()); } if (cookie.domain() != null) { add(buf, CookieHeaderNames.DOMAIN, cookie.domain()); } if (cookie.isSecure()) { add(buf, CookieHeaderNames.SECURE); } if (cookie.isHttpOnly()) { add(buf, CookieHeaderNames.HTTPONLY); } return stripTrailingSeparator(buf); } /** Deduplicate a list of encoded cookies by keeping only the last instance with a given name. * * @param encoded The list of encoded cookies. * @param nameToLastIndex A map from cookie name to index of last cookie instance. * @return The encoded list with all but the last instance of a named cookie. */ private static List<String> dedup(List<String> encoded, Map<String, Integer> nameToLastIndex) { boolean[] isLastInstance = new boolean[encoded.size()]; for (int idx : nameToLastIndex.values()) { isLastInstance[idx] = true; } List<String> dedupd = new ArrayList<String>(nameToLastIndex.size()); for (int i = 0, n = encoded.size(); i < n; i++) { if (isLastInstance[i]) { dedupd.add(encoded.get(i)); } } return dedupd; } /** * Batch encodes cookies into Set-Cookie header values. * * @param cookies a bunch of cookies * @return the corresponding bunch of Set-Cookie headers */ public List<String> encode(Cookie... cookies) { if (checkNotNull(cookies, "cookies").length == 0) { return Collections.emptyList(); } List<String> encoded = new ArrayList<String>(cookies.length); Map<String, Integer> nameToIndex = strict && cookies.length > 1 ? new HashMap<String, Integer>() : null; boolean hasDupdName = false; for (int i = 0; i < cookies.length; i++) { Cookie c = cookies[i]; encoded.add(encode(c)); if (nameToIndex != null) { hasDupdName |= nameToIndex.put(c.name(), i) != null; } } return hasDupdName ? dedup(encoded, nameToIndex) : encoded; } /** * Batch encodes cookies into Set-Cookie header values. * * @param cookies a bunch of cookies * @return the corresponding bunch of Set-Cookie headers */ public List<String> encode(Collection<? extends Cookie> cookies) { if (checkNotNull(cookies, "cookies").isEmpty()) { return Collections.emptyList(); } List<String> encoded = new ArrayList<String>(cookies.size()); Map<String, Integer> nameToIndex = strict && cookies.size() > 1 ? new HashMap<String, Integer>() : null; int i = 0; boolean hasDupdName = false; for (Cookie c : cookies) { encoded.add(encode(c)); if (nameToIndex != null) { hasDupdName |= nameToIndex.put(c.name(), i++) != null; } } return hasDupdName ? dedup(encoded, nameToIndex) : encoded; } /** * Batch encodes cookies into Set-Cookie header values. * * @param cookies a bunch of cookies * @return the corresponding bunch of Set-Cookie headers */ public List<String> encode(Iterable<? extends Cookie> cookies) { Iterator<? extends Cookie> cookiesIt = checkNotNull(cookies, "cookies").iterator(); if (!cookiesIt.hasNext()) { return Collections.emptyList(); } List<String> encoded = new ArrayList<String>(); Cookie firstCookie = cookiesIt.next(); Map<String, Integer> nameToIndex = strict && cookiesIt.hasNext() ? new HashMap<String, Integer>() : null; int i = 0; encoded.add(encode(firstCookie)); boolean hasDupdName = nameToIndex != null && nameToIndex.put(firstCookie.name(), i++) != null; while (cookiesIt.hasNext()) { Cookie c = cookiesIt.next(); encoded.add(encode(c)); if (nameToIndex != null) { hasDupdName |= nameToIndex.put(c.name(), i++) != null; } } return hasDupdName ? dedup(encoded, nameToIndex) : encoded; } }