Java tutorial
/* * Copyright (c) 2011-2019 Contributors to the Eclipse Foundation * * This program and the accompanying materials are made available under the * terms of the Eclipse Public License 2.0 which is available at * http://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0 * which is available at https://www.apache.org/licenses/LICENSE-2.0. * * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 */ package io.vertx.core.eventbus.impl; import io.vertx.core.buffer.Buffer; import io.vertx.core.eventbus.MessageCodec; import io.vertx.core.eventbus.ReplyException; import io.vertx.core.eventbus.impl.codecs.*; import io.vertx.core.json.JsonArray; import io.vertx.core.json.JsonObject; import java.util.Objects; import java.util.concurrent.ConcurrentHashMap; import java.util.concurrent.ConcurrentMap; /** * @author <a href="http://tfox.org">Tim Fox</a> */ public class CodecManager { // The standard message codecs public static final MessageCodec<String, String> PING_MESSAGE_CODEC = new PingMessageCodec(); public static final MessageCodec<String, String> NULL_MESSAGE_CODEC = new NullMessageCodec(); public static final MessageCodec<String, String> STRING_MESSAGE_CODEC = new StringMessageCodec(); public static final MessageCodec<Buffer, Buffer> BUFFER_MESSAGE_CODEC = new BufferMessageCodec(); public static final MessageCodec<JsonObject, JsonObject> JSON_OBJECT_MESSAGE_CODEC = new JsonObjectMessageCodec(); public static final MessageCodec<JsonArray, JsonArray> JSON_ARRAY_MESSAGE_CODEC = new JsonArrayMessageCodec(); public static final MessageCodec<byte[], byte[]> BYTE_ARRAY_MESSAGE_CODEC = new ByteArrayMessageCodec(); public static final MessageCodec<Integer, Integer> INT_MESSAGE_CODEC = new IntMessageCodec(); public static final MessageCodec<Long, Long> LONG_MESSAGE_CODEC = new LongMessageCodec(); public static final MessageCodec<Float, Float> FLOAT_MESSAGE_CODEC = new FloatMessageCodec(); public static final MessageCodec<Double, Double> DOUBLE_MESSAGE_CODEC = new DoubleMessageCodec(); public static final MessageCodec<Boolean, Boolean> BOOLEAN_MESSAGE_CODEC = new BooleanMessageCodec(); public static final MessageCodec<Short, Short> SHORT_MESSAGE_CODEC = new ShortMessageCodec(); public static final MessageCodec<Character, Character> CHAR_MESSAGE_CODEC = new CharMessageCodec(); public static final MessageCodec<Byte, Byte> BYTE_MESSAGE_CODEC = new ByteMessageCodec(); public static final MessageCodec<ReplyException, ReplyException> REPLY_EXCEPTION_MESSAGE_CODEC = new ReplyExceptionMessageCodec(); private final MessageCodec[] systemCodecs; private final ConcurrentMap<String, MessageCodec> userCodecMap = new ConcurrentHashMap<>(); private final ConcurrentMap<Class, MessageCodec> defaultCodecMap = new ConcurrentHashMap<>(); public CodecManager() { this.systemCodecs = codecs(NULL_MESSAGE_CODEC, PING_MESSAGE_CODEC, STRING_MESSAGE_CODEC, BUFFER_MESSAGE_CODEC, JSON_OBJECT_MESSAGE_CODEC, JSON_ARRAY_MESSAGE_CODEC, BYTE_ARRAY_MESSAGE_CODEC, INT_MESSAGE_CODEC, LONG_MESSAGE_CODEC, FLOAT_MESSAGE_CODEC, DOUBLE_MESSAGE_CODEC, BOOLEAN_MESSAGE_CODEC, SHORT_MESSAGE_CODEC, CHAR_MESSAGE_CODEC, BYTE_MESSAGE_CODEC, REPLY_EXCEPTION_MESSAGE_CODEC); } public MessageCodec lookupCodec(Object body, String codecName) { MessageCodec codec; if (codecName != null) { codec = userCodecMap.get(codecName); if (codec == null) { throw new IllegalArgumentException("No message codec for name: " + codecName); } } else if (body == null) { codec = NULL_MESSAGE_CODEC; } else if (body instanceof String) { codec = STRING_MESSAGE_CODEC; } else if (body instanceof Buffer) { codec = BUFFER_MESSAGE_CODEC; } else if (body instanceof JsonObject) { codec = JSON_OBJECT_MESSAGE_CODEC; } else if (body instanceof JsonArray) { codec = JSON_ARRAY_MESSAGE_CODEC; } else if (body instanceof byte[]) { codec = BYTE_ARRAY_MESSAGE_CODEC; } else if (body instanceof Integer) { codec = INT_MESSAGE_CODEC; } else if (body instanceof Long) { codec = LONG_MESSAGE_CODEC; } else if (body instanceof Float) { codec = FLOAT_MESSAGE_CODEC; } else if (body instanceof Double) { codec = DOUBLE_MESSAGE_CODEC; } else if (body instanceof Boolean) { codec = BOOLEAN_MESSAGE_CODEC; } else if (body instanceof Short) { codec = SHORT_MESSAGE_CODEC; } else if (body instanceof Character) { codec = CHAR_MESSAGE_CODEC; } else if (body instanceof Byte) { codec = BYTE_MESSAGE_CODEC; } else if (body instanceof ReplyException) { codec = defaultCodecMap.get(body.getClass()); if (codec == null) { codec = REPLY_EXCEPTION_MESSAGE_CODEC; } } else { codec = defaultCodecMap.get(body.getClass()); if (codec == null) { throw new IllegalArgumentException("No message codec for type: " + body.getClass()); } } return codec; } public MessageCodec getCodec(String codecName) { return userCodecMap.get(codecName); } public void registerCodec(MessageCodec codec) { Objects.requireNonNull(codec, "codec"); Objects.requireNonNull(codec.name(), "code.name()"); checkSystemCodec(codec); if (userCodecMap.containsKey(codec.name())) { throw new IllegalStateException("Already a codec registered with name " + codec.name()); } userCodecMap.put(codec.name(), codec); } public void unregisterCodec(String name) { Objects.requireNonNull(name); userCodecMap.remove(name); } public <T> void registerDefaultCodec(Class<T> clazz, MessageCodec<T, ?> codec) { Objects.requireNonNull(clazz); Objects.requireNonNull(codec, "codec"); Objects.requireNonNull(codec.name(), "code.name()"); checkSystemCodec(codec); if (defaultCodecMap.containsKey(clazz)) { throw new IllegalStateException("Already a default codec registered for class " + clazz); } if (userCodecMap.containsKey(codec.name())) { throw new IllegalStateException("Already a codec registered with name " + codec.name()); } defaultCodecMap.put(clazz, codec); userCodecMap.put(codec.name(), codec); } public void unregisterDefaultCodec(Class clazz) { Objects.requireNonNull(clazz); MessageCodec codec = defaultCodecMap.remove(clazz); if (codec != null) { userCodecMap.remove(codec.name()); } } public MessageCodec[] systemCodecs() { return systemCodecs; } private void checkSystemCodec(MessageCodec codec) { if (codec.systemCodecID() != -1) { throw new IllegalArgumentException("Can't register a system codec"); } } private MessageCodec[] codecs(MessageCodec... codecs) { MessageCodec[] arr = new MessageCodec[codecs.length]; for (MessageCodec codec : codecs) { arr[codec.systemCodecID()] = codec; } return arr; } }