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/* * Copyright 2015 the original author or authors. * * 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 com.heliosapm.mws.server.net.json; import java.io.IOException; import java.io.InputStream; import com.fasterxml.jackson.core.JsonFactory; import com.fasterxml.jackson.core.JsonParseException; import com.fasterxml.jackson.core.JsonParser; import com.fasterxml.jackson.core.JsonProcessingException; import com.fasterxml.jackson.core.type.TypeReference; import com.fasterxml.jackson.databind.JsonMappingException; import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.databind.node.JsonNodeFactory; import com.fasterxml.jackson.databind.util.JSONPObject; /** * <p>Title: JSON</p> * <p>Description: Static jackson Json methods</p> * <p>Company: Helios Development Group LLC</p> * <p>Mostly copied from <a href="http://opentsdb.net">OpenTSDB</a>. * @author Whitehead (nwhitehead AT heliosdev DOT org) * <p><code>com.heliosapm.mws.server.net.json.JSON</code></p> */ public class JSON { private static final ObjectMapper jsonMapper = new ObjectMapper(); static { jsonMapper.configure(JsonParser.Feature.ALLOW_NON_NUMERIC_NUMBERS, true); jsonMapper.configure(JsonParser.Feature.ALLOW_SINGLE_QUOTES, true); } /** * Deserializes a JSON formatted string to a specific class type * <b>Note:</b> If you get mapping exceptions you may need to provide a * TypeReference * @param json The string to deserialize * @param pojo The class type of the object used for deserialization * @return An object of the {@code pojo} type * @param <T> The expected type of the return object * @throws IllegalArgumentException if the data or class was null or parsing * failed * @throws JSONException if the data could not be parsed */ public static final <T> T parseToObject(final String json, final Class<T> pojo) { if (json == null || json.isEmpty()) throw new IllegalArgumentException("Incoming data was null or empty"); if (pojo == null) throw new IllegalArgumentException("Missing class type"); try { return jsonMapper.readValue(json, pojo); } catch (JsonParseException e) { throw new IllegalArgumentException(e); } catch (JsonMappingException e) { throw new IllegalArgumentException(e); } catch (IOException e) { throw new JSONException(e); } } /** * Deserializes a JSON formatted byte array to a specific class type * <b>Note:</b> If you get mapping exceptions you may need to provide a * TypeReference * @param json The byte array to deserialize * @param pojo The class type of the object used for deserialization * @return An object of the {@code pojo} type * @param <T> The expected type of the return object * @throws IllegalArgumentException if the data or class was null or parsing * failed * @throws JSONException if the data could not be parsed */ public static final <T> T parseToObject(final byte[] json, final Class<T> pojo) { if (json == null) throw new IllegalArgumentException("Incoming data was null"); if (pojo == null) throw new IllegalArgumentException("Missing class type"); try { return jsonMapper.readValue(json, pojo); } catch (JsonParseException e) { throw new IllegalArgumentException(e); } catch (JsonMappingException e) { throw new IllegalArgumentException(e); } catch (IOException e) { throw new JSONException(e); } } /** * Deserializes a JSON formatted string to a specific class type * @param json The string to deserialize * @param type A type definition for a complex object * @return An object of the {@code pojo} type * @param <T> The expected type of the return object * @throws IllegalArgumentException if the data or type was null or parsing * failed * @throws JSONException if the data could not be parsed */ @SuppressWarnings("unchecked") public static final <T> T parseToObject(final String json, final TypeReference<T> type) { if (json == null || json.isEmpty()) throw new IllegalArgumentException("Incoming data was null or empty"); if (type == null) throw new IllegalArgumentException("Missing type reference"); try { return (T) jsonMapper.readValue(json, type); } catch (JsonParseException e) { throw new IllegalArgumentException(e); } catch (JsonMappingException e) { throw new IllegalArgumentException(e); } catch (IOException e) { throw new JSONException(e); } } /** * Deserializes a JSON formatted byte array to a specific class type * @param json The byte array to deserialize * @param type A type definition for a complex object * @return An object of the {@code pojo} type * @param <T> The expected type of the return object * @throws IllegalArgumentException if the data or type was null or parsing * failed * @throws JSONException if the data could not be parsed */ @SuppressWarnings("unchecked") public static final <T> T parseToObject(final byte[] json, final TypeReference<T> type) { if (json == null) throw new IllegalArgumentException("Incoming data was null"); if (type == null) throw new IllegalArgumentException("Missing type reference"); try { return (T) jsonMapper.readValue(json, type); } catch (JsonParseException e) { throw new IllegalArgumentException(e); } catch (JsonMappingException e) { throw new IllegalArgumentException(e); } catch (IOException e) { throw new JSONException(e); } } /** * Parses a JSON formatted string into raw tokens for streaming or tree * iteration * <b>Warning:</b> This method can parse an invalid JSON object without * throwing an error until you start processing the data * @param json The string to parse * @return A JsonParser object to be used for iteration * @throws IllegalArgumentException if the data was null or parsing failed * @throws JSONException if the data could not be parsed */ public static final JsonParser parseToStream(final String json) { if (json == null || json.isEmpty()) throw new IllegalArgumentException("Incoming data was null or empty"); try { return jsonMapper.getFactory().createParser(json); } catch (JsonParseException e) { throw new IllegalArgumentException(e); } catch (IOException e) { throw new JSONException(e); } } /** * Parses a JSON formatted byte array into raw tokens for streaming or tree * iteration * <b>Warning:</b> This method can parse an invalid JSON object without * throwing an error until you start processing the data * @param json The byte array to parse * @return A JsonParser object to be used for iteration * @throws IllegalArgumentException if the data was null or parsing failed * @throws JSONException if the data could not be parsed */ public static final JsonParser parseToStream(final byte[] json) { if (json == null) throw new IllegalArgumentException("Incoming data was null"); try { return jsonMapper.getFactory().createParser(json); } catch (JsonParseException e) { throw new IllegalArgumentException(e); } catch (IOException e) { throw new JSONException(e); } } /** * Parses a JSON formatted inputs stream into raw tokens for streaming or tree * iteration * <b>Warning:</b> This method can parse an invalid JSON object without * throwing an error until you start processing the data * @param json The input stream to parse * @return A JsonParser object to be used for iteration * @throws IllegalArgumentException if the data was null or parsing failed * @throws JSONException if the data could not be parsed */ public static final JsonParser parseToStream(final InputStream json) { if (json == null) throw new IllegalArgumentException("Incoming data was null"); try { return jsonMapper.getFactory().createParser(json); } catch (JsonParseException e) { throw new IllegalArgumentException(e); } catch (IOException e) { throw new JSONException(e); } } /** * Serializes the given object to a JSON string * @param object The object to serialize * @return A JSON formatted string * @throws IllegalArgumentException if the object was null * @throws JSONException if the object could not be serialized * @throws IOException Thrown when there was an issue reading the object */ @SuppressWarnings("javadoc") public static final String serializeToString(final Object object) { if (object == null) throw new IllegalArgumentException("Object was null"); try { return jsonMapper.writeValueAsString(object); } catch (JsonProcessingException e) { throw new JSONException(e); } } /** * Serializes the given object to a JSON byte array * @param object The object to serialize * @return A JSON formatted byte array * @throws IllegalArgumentException if the object was null * @throws JSONException if the object could not be serialized * @throws IOException Thrown when there was an issue reading the object */ @SuppressWarnings("javadoc") public static final byte[] serializeToBytes(final Object object) { if (object == null) throw new IllegalArgumentException("Object was null"); try { return jsonMapper.writeValueAsBytes(object); } catch (JsonProcessingException e) { throw new JSONException(e); } } /** * Serializes the given object and wraps it in a callback function * i.e. <callback>(<json>) * Note: This will not append a trailing semicolon * @param callback The name of the Javascript callback to prepend * @param object The object to serialize * @return A JSONP formatted string * @throws IllegalArgumentException if the callback method name was missing * or object was null * @throws JSONException if the object could not be serialized * @throws IOException Thrown when there was an issue reading the object */ @SuppressWarnings("javadoc") public static final String serializeToJSONPString(final String callback, final Object object) { if (callback == null || callback.isEmpty()) throw new IllegalArgumentException("Missing callback name"); if (object == null) throw new IllegalArgumentException("Object was null"); try { return jsonMapper.writeValueAsString(new JSONPObject(callback, object)); } catch (JsonProcessingException e) { throw new JSONException(e); } } /** * Serializes the given object and wraps it in a callback function * i.e. <callback>(<json>) * Note: This will not append a trailing semicolon * @param callback The name of the Javascript callback to prepend * @param object The object to serialize * @return A JSONP formatted byte array * @throws IllegalArgumentException if the callback method name was missing * or object was null * @throws JSONException if the object could not be serialized * @throws IOException Thrown when there was an issue reading the object */ @SuppressWarnings("javadoc") public static final byte[] serializeToJSONPBytes(final String callback, final Object object) { if (callback == null || callback.isEmpty()) throw new IllegalArgumentException("Missing callback name"); if (object == null) throw new IllegalArgumentException("Object was null"); try { return jsonMapper.writeValueAsBytes(new JSONPObject(callback, object)); } catch (JsonProcessingException e) { throw new JSONException(e); } } /** * Returns a reference to the static ObjectMapper * @return The ObjectMapper */ public final static ObjectMapper getMapper() { return jsonMapper; } /** * Returns a reference to the JsonFactory for streaming creation * @return The JsonFactory object */ public final static JsonFactory getFactory() { return jsonMapper.getFactory(); } /** * @return */ public final static JsonNodeFactory getNodeFactory() { return jsonMapper.getNodeFactory(); } private JSON() { } }