Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF 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.kyligence.benchmark.loadtest.util; import com.fasterxml.jackson.core.JsonGenerationException; import com.fasterxml.jackson.core.JsonParseException; import com.fasterxml.jackson.core.JsonProcessingException; import com.fasterxml.jackson.core.type.TypeReference; import com.fasterxml.jackson.databind.DeserializationFeature; import com.fasterxml.jackson.databind.JsonMappingException; import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.databind.SerializationFeature; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.Reader; import java.util.HashMap; import java.util.Map; public class JsonUtil { // reuse the object mapper to save memory footprint private static final ObjectMapper mapper = new ObjectMapper(); private static final ObjectMapper indentMapper = new ObjectMapper(); static { mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false); indentMapper.configure(SerializationFeature.INDENT_OUTPUT, true); } public static <T> T readValue(File src, Class<T> valueType) throws IOException, JsonParseException, JsonMappingException { return mapper.readValue(src, valueType); } public static <T> T readValue(String content, Class<T> valueType) throws IOException, JsonParseException, JsonMappingException { return mapper.readValue(content, valueType); } public static <T> T readValue(Reader src, Class<T> valueType) throws IOException, JsonParseException, JsonMappingException { return mapper.readValue(src, valueType); } public static <T> T readValue(InputStream src, Class<T> valueType) throws IOException, JsonParseException, JsonMappingException { return mapper.readValue(src, valueType); } public static <T> T readValue(byte[] src, Class<T> valueType) throws IOException, JsonParseException, JsonMappingException { return mapper.readValue(src, valueType); } public static Map<String, String> readValueAsMap(String content) throws IOException { TypeReference<HashMap<String, String>> typeRef = new TypeReference<HashMap<String, String>>() { }; return mapper.readValue(content, typeRef); } public static void writeValueIndent(OutputStream out, Object value) throws IOException, JsonGenerationException, JsonMappingException { indentMapper.writeValue(out, value); } public static void writeValue(OutputStream out, Object value) throws IOException, JsonGenerationException, JsonMappingException { mapper.writeValue(out, value); } public static String writeValueAsString(Object value) throws JsonProcessingException { return mapper.writeValueAsString(value); } public static byte[] writeValueAsBytes(Object value) throws JsonProcessingException { return mapper.writeValueAsBytes(value); } public static String writeValueAsIndentString(Object value) throws JsonProcessingException { return indentMapper.writeValueAsString(value); } }