com.evrythng.java.wrapper.util.JSONUtils.java Source code

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Here is the source code for com.evrythng.java.wrapper.util.JSONUtils.java

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/*
 * (c) Copyright Reserved EVRYTHNG Limited 2016. All rights reserved.
 * Use of this material is subject to license.
 * Copying and unauthorised use of this material strictly prohibited.
 */
package com.evrythng.java.wrapper.util;

import com.evrythng.java.wrapper.exception.WrappedRuntimeException;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.databind.deser.std.StdScalarDeserializer;
import com.fasterxml.jackson.databind.deser.std.StringDeserializer;
import com.fasterxml.jackson.databind.module.SimpleModule;
import com.fasterxml.jackson.databind.util.ISO8601DateFormat;
import org.apache.commons.lang3.StringUtils;

import java.io.IOException;
import java.io.InputStream;

/**
 * JSON utilities based on Jackson {@link ObjectMapper}.
 */
public final class JSONUtils {

    /**
     * ObjectMapper singleton.
     */
    public static final ObjectMapper OBJECT_MAPPER = createObjectMapper();

    private JSONUtils() {
        /* Hide default constructor */
    }

    /**
     * Deserializes the provided {@code json} {@link String} to a native {@code type} representation.
     *
     * @return Deserialized native instance
     *
     * @deprecated since 1.15
     */
    @Deprecated
    public static <T> T read(final String json, final Class<T> type) {

        try {
            return OBJECT_MAPPER.readValue(json, type);
        } catch (Exception e) {
            // Wrap into unchecked exception:
            throw new WrappedRuntimeException(e);
        }
    }

    /**
     * Deserializes the provided {@code json} {@link String} to a native {@code type} representation.
     *
     * @return Deserialized native instance
     */
    public static <T> T read(final String json, final TypeReference<T> type) {

        try {
            return OBJECT_MAPPER.readValue(json, type);
        } catch (Exception e) {
            // Wrap into unchecked exception:
            throw new WrappedRuntimeException(e);
        }
    }

    /**
     * Deserializes the provided {@link InputStream} to a native {@code type} representation.
     *
     * @return Deserialized native instance
     *
     * @deprecated since 1.15
     */
    @Deprecated
    public static <T> T read(final InputStream inputStream, final TypeReference<T> type) {

        try {
            return OBJECT_MAPPER.readValue(inputStream, type);
        } catch (Exception e) {
            // Wrap into unchecked exception:
            throw new WrappedRuntimeException(e);
        }
    }

    /**
     * Deserializes the provided {@link InputStream} to a native {@code valueType} representation.
     *
     * @return Deserialized native instance
     *
     * @deprecated since 1.15
     */
    @Deprecated
    public static <T> T read(final InputStream inputStream, final Class<T> valueType) {

        try {
            return OBJECT_MAPPER.readValue(inputStream, valueType);
        } catch (Exception e) {
            // Wrap into unchecked exception:
            throw new WrappedRuntimeException(e);
        }
    }

    /**
     * Converts the provided {@code object} to an JSON {@link String}.
     */
    public static String write(final Object object) {

        try {
            return OBJECT_MAPPER.writeValueAsString(object);
        } catch (Exception e) {
            // Wrap into unchecked exception:
            throw new WrappedRuntimeException(e);
        }
    }

    /**
     * Creates a pre-configured {@link ObjectMapper}.
     */
    public static ObjectMapper createObjectMapper() {

        ObjectMapper mapper = new ObjectMapper();

        mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
        mapper.configure(SerializationFeature.WRITE_NULL_MAP_VALUES, false);
        mapper.configure(SerializationFeature.ORDER_MAP_ENTRIES_BY_KEYS, true);
        mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
        mapper.setDateFormat(new ISO8601DateFormat());

        mapper.registerModule(new CoreModule());

        return mapper;
    }

    private static class CoreModule extends SimpleModule {

        private CoreModule() {

            addDeserializer(String.class, new StdScalarDeserializer<String>(String.class) {

                private static final long serialVersionUID = 6977627268309308664L;
                private final StringDeserializer STRING_DESERIALIZER = new StringDeserializer();

                @Override
                public String deserialize(final JsonParser jp, final DeserializationContext ctx)
                        throws IOException {

                    return StringUtils.trim(STRING_DESERIALIZER.deserialize(jp, ctx));
                }
            });
        }
    }
}