com.lightbox.android.webservices.processors.JacksonProcessor.java Source code

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Here is the source code for com.lightbox.android.webservices.processors.JacksonProcessor.java

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/**
 * Copyright (c) 2012 Lightbox
 *
 * 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.lightbox.android.webservices.processors;

import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Set;

import org.apache.commons.io.IOUtils;
import org.codehaus.jackson.JsonGenerationException;
import org.codehaus.jackson.JsonParseException;
import org.codehaus.jackson.map.DeserializationConfig;
import org.codehaus.jackson.map.JsonMappingException;
import org.codehaus.jackson.map.ObjectMapper;
import org.codehaus.jackson.map.PropertyNamingStrategy;
import org.codehaus.jackson.map.ser.FilterProvider;
import org.codehaus.jackson.map.ser.impl.SimpleBeanPropertyFilter;
import org.codehaus.jackson.map.ser.impl.SimpleFilterProvider;

import android.util.Log;

/** 
 * JacksonProcessor 
 * @author Fabien Devos
 */
public class JacksonProcessor<T> implements Processor<T> {
    /** Used to tag logs */
    //@SuppressWarnings("unused")
    private static final String TAG = "JacksonProcessor";

    public static final String PROPERTIES_FILTER = "propertiesFilter";

    // Can be reused as long as it is configured first 
    private static ObjectMapper sObjectMapper = new ObjectMapper();
    private static ObjectMapper sObjectMapperWithoutNamingStrategy = new ObjectMapper();
    static {
        sObjectMapper.configure(DeserializationConfig.Feature.FAIL_ON_UNKNOWN_PROPERTIES, false);
        sObjectMapper.setPropertyNamingStrategy(PropertyNamingStrategy.CAMEL_CASE_TO_LOWER_CASE_WITH_UNDERSCORES);
        sObjectMapperWithoutNamingStrategy.configure(DeserializationConfig.Feature.FAIL_ON_UNKNOWN_PROPERTIES,
                false);
    }

    @Override
    public T parse(Class<T> parsedClass, InputStream source) throws ParsingException {
        return parse(parsedClass, source, true);
    }

    public T parse(Class<T> parsedClass, InputStream source, boolean useNamingStrategy) throws ParsingException {
        T parsedObject = null;
        try {
            ObjectMapper objectMapper = useNamingStrategy ? sObjectMapper : sObjectMapperWithoutNamingStrategy;
            parsedObject = objectMapper.readValue(source, parsedClass);
        } catch (JsonParseException e) {
            Log.w(TAG, e);
            throw new ParsingException(e);
        } catch (JsonMappingException e) {
            Log.w(TAG, e);
            throw new ParsingException(e);
        } catch (IOException e) {
            Log.w(TAG, e);
            throw new ParsingException(e);
        }
        return parsedObject;
    }

    @Override
    public String generate(T sourceObject, Set<String> propertiesToInclude) throws GenerationException {
        return generate(sourceObject, propertiesToInclude, true);
    }

    public String generate(T sourceObject, Set<String> propertiesToInclude, boolean useNamingStrategy)
            throws GenerationException {
        String generatedString = null;
        try {
            ObjectMapper objectMapper = useNamingStrategy ? sObjectMapper : sObjectMapperWithoutNamingStrategy;
            // Filtering properties
            if (propertiesToInclude != null) {
                FilterProvider filterProvider = new SimpleFilterProvider().addFilter(PROPERTIES_FILTER,
                        SimpleBeanPropertyFilter.filterOutAllExcept(propertiesToInclude));
                generatedString = objectMapper.writer(filterProvider).writeValueAsString(sourceObject);
                // Do not filter properties
            } else {
                generatedString = objectMapper.writeValueAsString(sourceObject);
            }
        } catch (JsonGenerationException e) {
            Log.w(TAG, e);
            throw new GenerationException(e);
        } catch (JsonMappingException e) {
            Log.w(TAG, e);
            throw new GenerationException(e);
        } catch (IOException e) {
            Log.w(TAG, e);
            throw new GenerationException(e);
        }
        return generatedString;
    }

    //----------------------------------------------
    // Utility methods

    @SuppressWarnings("unchecked")
    public static HashMap<String, Object> jsonToMap(String json) throws ParsingException {
        HashMap<String, Object> map = null;
        // To Map
        if (json != null) {
            @SuppressWarnings("rawtypes")
            JacksonProcessor<HashMap> processor = new JacksonProcessor<HashMap>();
            map = processor.parse(HashMap.class, IOUtils.toInputStream(json));
        }
        return map;
    }

    public static String mapToJson(HashMap<String, Object> map) throws GenerationException {
        String json = null;
        // To JSON
        if (map != null) {
            @SuppressWarnings("rawtypes")
            JacksonProcessor<HashMap> processor = new JacksonProcessor<HashMap>();
            json = processor.generate(map, null);
        }
        return json;
    }

}