| /* |
| * Copyright (c) 2015, 2016, 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 |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package jdk.incubator.http.internal.websocket; |
| |
| import java.nio.ByteBuffer; |
| import java.nio.CharBuffer; |
| import java.nio.charset.CharacterCodingException; |
| import java.nio.charset.CharsetDecoder; |
| import java.nio.charset.CoderResult; |
| import java.nio.charset.CodingErrorAction; |
| |
| import static java.lang.System.Logger.Level.WARNING; |
| import static java.nio.charset.StandardCharsets.UTF_8; |
| import static jdk.incubator.http.internal.common.Utils.EMPTY_BYTEBUFFER; |
| import static jdk.incubator.http.internal.websocket.WebSocketImpl.logger; |
| |
| final class UTF8AccumulatingDecoder { |
| |
| private final CharsetDecoder decoder = UTF_8.newDecoder(); |
| |
| { |
| decoder.onMalformedInput(CodingErrorAction.REPORT); |
| decoder.onUnmappableCharacter(CodingErrorAction.REPORT); |
| } |
| |
| private ByteBuffer leftovers = EMPTY_BYTEBUFFER; |
| |
| CharBuffer decode(ByteBuffer in, boolean endOfInput) |
| throws CharacterCodingException |
| { |
| ByteBuffer b; |
| int rem = leftovers.remaining(); |
| if (rem != 0) { |
| // We won't need this wasteful allocation & copying when JDK-8155222 |
| // has been resolved |
| b = ByteBuffer.allocate(rem + in.remaining()); |
| b.put(leftovers).put(in).flip(); |
| } else { |
| b = in; |
| } |
| CharBuffer out = CharBuffer.allocate(b.remaining()); |
| CoderResult r = decoder.decode(b, out, endOfInput); |
| if (r.isError()) { |
| r.throwException(); |
| } |
| if (b.hasRemaining()) { |
| leftovers = ByteBuffer.allocate(b.remaining()).put(b).flip(); |
| } else { |
| leftovers = EMPTY_BYTEBUFFER; |
| } |
| // Since it's UTF-8, the assumption is leftovers.remaining() < 4 |
| // (i.e. small). Otherwise a shared buffer should be used |
| if (!(leftovers.remaining() < 4)) { |
| logger.log(WARNING, |
| "The size of decoding leftovers is greater than expected: {0}", |
| leftovers.remaining()); |
| } |
| b.position(b.limit()); // As if we always read to the end |
| // Decoder promises that in the case of endOfInput == true: |
| // "...any remaining undecoded input will be treated as being |
| // malformed" |
| assert !(endOfInput && leftovers.hasRemaining()) : endOfInput + ", " + leftovers; |
| if (endOfInput) { |
| r = decoder.flush(out); |
| decoder.reset(); |
| if (r.isOverflow()) { |
| // FIXME: for now I know flush() does nothing. But the |
| // implementation of UTF8 decoder might change. And if now |
| // flush() is a no-op, it is not guaranteed to remain so in |
| // the future |
| throw new InternalError("Not yet implemented"); |
| } |
| } |
| return out.flip(); |
| } |
| } |