org.bremersee.sms.ExtensionUtils.java Source code

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Here is the source code for org.bremersee.sms.ExtensionUtils.java

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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 org.bremersee.sms;

import java.io.IOException;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;

import org.apache.commons.lang3.Validate;
import org.w3c.dom.Node;

import com.fasterxml.jackson.databind.ObjectMapper;

/**
 * <p>
 * Utility methods to transform an extension that was serialized by a
 * {@link JAXBContext} or an {@link ObjectMapper} into a POJO.
 * </p>
 * 
 * @author Christian Bremer
 */
public abstract class ExtensionUtils {

    private ExtensionUtils() {
    }

    private static final ObjectMapper DEFAULT_OBJECT_MAPPER = new ObjectMapper();

    private static final Map<java.lang.reflect.AnnotatedElement, JAXBContext> JAXB_CONTEXTS = new ConcurrentHashMap<>();

    private static JAXBContext getJaxbContext(Class<?> valueType) throws JAXBException {
        JAXBContext jaxbContext = JAXB_CONTEXTS.get(valueType.getPackage());
        if (jaxbContext == null) {
            jaxbContext = JAXB_CONTEXTS.get(valueType);
        }
        if (jaxbContext == null) {
            try {
                jaxbContext = JAXBContext.newInstance(valueType.getPackage().getName());
            } catch (JAXBException e) {
                jaxbContext = JAXBContext.newInstance(valueType);
                JAXB_CONTEXTS.put(valueType, jaxbContext);
            }
        }
        return jaxbContext;
    }

    /**
     * Transforms a XML node or a JSON map into an object.
     * 
     * @param xmlNodeOrJsonMap
     *            the XML node or JSON map
     * @param valueType
     *            the class of the target object
     * @param jaxbContext
     *            the {@link JAXBContext} (can be null)
     * @param objectMapper
     *            the JSON object mapper (optional)
     * @return the target object
     * @throws Exception
     *             if transformation fails
     */
    @SuppressWarnings("unchecked")
    public static <T> T transform(Object xmlNodeOrJsonMap, Class<T> valueType, JAXBContext jaxbContext,
            ObjectMapper objectMapper) throws Exception {
        if (xmlNodeOrJsonMap == null) {
            return null;
        }
        Validate.notNull(valueType, "valueType must not be null");
        if (valueType.isAssignableFrom(xmlNodeOrJsonMap.getClass())) {
            return valueType.cast(xmlNodeOrJsonMap);
        }
        if (xmlNodeOrJsonMap instanceof Node) {
            return xmlNodeToObject((Node) xmlNodeOrJsonMap, valueType, jaxbContext);
        }
        if (xmlNodeOrJsonMap instanceof Map) {
            return jsonMapToObject((Map<String, Object>) xmlNodeOrJsonMap, valueType, objectMapper);
        }
        throw new IllegalArgumentException("xmlNodeOrJsonMap must be of type " + valueType + ", "
                + Node.class.getName() + " or of type " + Map.class.getName());
    }

    /**
     * Transforms a XML node or a JSON map into an object.
     * 
     * @param xmlNodeOrJsonMap
     *            the XML node or JSON map
     * @param valueType
     *            the class of the target object
     * @param jaxbContextOrObjectMapper
     *            a {@link JAXBContext} or a {@link ObjectMapper} (can be null)
     * @return the target object
     * @throws Exception
     *             if transformation fails
     * @deprecated Use
     *             {@link ExtensionUtils#transform(Object, Class, JAXBContext, ObjectMapper)}
     *             instead.
     */
    @Deprecated
    @SuppressWarnings("unchecked")
    public static <T> T transform(Object xmlNodeOrJsonMap, Class<T> valueType, Object jaxbContextOrObjectMapper)
            throws Exception {
        if (xmlNodeOrJsonMap == null) {
            return null;
        }
        Validate.notNull(valueType, "valueType must not be null");
        if (valueType.isAssignableFrom(xmlNodeOrJsonMap.getClass())) {
            return valueType.cast(xmlNodeOrJsonMap);
        }
        if (xmlNodeOrJsonMap instanceof Node) {
            JAXBContext jaxbContext;
            if (jaxbContextOrObjectMapper != null && jaxbContextOrObjectMapper instanceof JAXBContext) {
                jaxbContext = (JAXBContext) jaxbContextOrObjectMapper;
            } else {
                jaxbContext = null;
            }
            return xmlNodeToObject((Node) xmlNodeOrJsonMap, valueType, jaxbContext);
        }
        if (xmlNodeOrJsonMap instanceof Map) {
            ObjectMapper objectMapper;
            if (jaxbContextOrObjectMapper != null && jaxbContextOrObjectMapper instanceof ObjectMapper) {
                objectMapper = (ObjectMapper) jaxbContextOrObjectMapper;
            } else {
                objectMapper = null;
            }
            return jsonMapToObject((Map<String, Object>) xmlNodeOrJsonMap, valueType, objectMapper);
        }
        throw new IllegalArgumentException(
                "xmlNodeOrJsonMap must be of type " + Node.class.getName() + " or of type " + Map.class.getName());
    }

    /**
     * Transforms a XML node into an object.
     * 
     * @param node
     *            the XML node
     * @param valueType
     *            the class of the target object
     * @param jaxbContext
     *            the {@link JAXBContext} (can be null)
     * @return the target object
     * @throws JAXBException
     *             if transformation fails
     */
    public static <T> T xmlNodeToObject(Node node, Class<T> valueType, JAXBContext jaxbContext)
            throws JAXBException {
        if (node == null) {
            return null;
        }
        Validate.notNull(valueType, "valueType must not be null");
        if (jaxbContext == null) {
            jaxbContext = getJaxbContext(valueType);
        }
        return valueType.cast(jaxbContext.createUnmarshaller().unmarshal(node));
    }

    /**
     * Transforms a JSON map into an object.
     * 
     * @param map
     *            the JSON map
     * @param valueType
     *            the class of the target object
     * @param objectMapper
     *            the JSON object mapper (can be null)
     * @return the target object
     * @throws IOException
     *             if transformation fails
     */
    public static <T> T jsonMapToObject(Map<String, Object> map, Class<T> valueType, ObjectMapper objectMapper)
            throws IOException {
        if (map == null) {
            return null;
        }
        Validate.notNull(valueType, "valueType must not be null");
        if (objectMapper == null) {
            objectMapper = DEFAULT_OBJECT_MAPPER;
        }
        return objectMapper.readValue(objectMapper.writeValueAsBytes(map), valueType);
    }

}