Java tutorial
/* * Copyright (C) 2016 Toshiaki Maki <makingx@gmail.com> * * Licensed 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 am.ik.sendgrid.util; import java.io.IOException; import java.io.InputStream; import java.io.UncheckedIOException; import java.util.function.Function; import com.fasterxml.jackson.core.JsonProcessingException; import com.fasterxml.jackson.core.type.TypeReference; import com.fasterxml.jackson.databind.ObjectMapper; import io.netty.buffer.ByteBuf; import io.netty.buffer.ByteBufAllocator; import io.netty.util.AsciiString; import reactor.core.Exceptions; import reactor.ipc.netty.http.HttpClientRequest; public final class JsonCodec { private static final AsciiString APPLICATION_JSON = new AsciiString("application/json; charset=utf-8"); private static final AsciiString CONTENT_TYPE = new AsciiString("Content-Type"); public static <T> Function<InputStream, T> decode(ObjectMapper objectMapper, Class<T> type) { return inputStream -> { try (InputStream in = inputStream) { return objectMapper.readValue(in, type); } catch (IOException e) { throw new UncheckedIOException("Unable to parse JSON Payload", e); } }; } public static <T> Function<InputStream, T> decode(ObjectMapper objectMapper, TypeReference<T> type) { return inputStream -> { try (InputStream in = inputStream) { return objectMapper.readValue(in, type); } catch (IOException e) { throw new UncheckedIOException("Unable to parse JSON Payload", e); } }; } public static <T> Function<T, ByteBuf> encode(ObjectMapper objectMapper, HttpClientRequest request) { request.header(CONTENT_TYPE, APPLICATION_JSON); return source -> encode(request.delegate().alloc(), objectMapper, source); } static <T> ByteBuf encode(ByteBufAllocator allocator, ObjectMapper objectMapper, T source) { try { return allocator.directBuffer().writeBytes(objectMapper.writeValueAsBytes(source)); } catch (JsonProcessingException e) { throw Exceptions.propagate(e); } } }