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<!-- https://mvnrepository.com/artifact/org.json/json -->
	<dependency>
	    <groupId>org.json</groupId>
	    <artifactId>json</artifactId>
	    <version>20170516</version>
	</dependency>
	
	<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->
	<dependency>
	    <groupId>com.fasterxml.jackson.core</groupId>
	    <artifactId>jackson-core</artifactId>
	    <version>2.9.1</version>
	</dependency>
	
	<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->
	<dependency>
	    <groupId>com.fasterxml.jackson.core</groupId>
	    <artifactId>jackson-databind</artifactId>
	    <version>2.9.1</version>
	</dependency>
	
	<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-annotations -->
	<dependency>
	    <groupId>com.fasterxml.jackson.core</groupId>
	    <artifactId>jackson-annotations</artifactId>
	    <version>2.9.1</version>
	</dependency>

package com.moov.solutions.ribeits.utils;

import java.io.IOException;
import java.io.StringWriter;
import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Arrays;
import java.util.Date;
import java.util.HashSet;
import java.util.Locale;
import java.util.Set;

import org.apache.commons.lang.StringUtils;

import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.ser.FilterProvider;
import com.fasterxml.jackson.databind.ser.impl.SimpleBeanPropertyFilter;
import com.fasterxml.jackson.databind.ser.impl.SimpleFilterProvider;
import com.moov.solutions.ribeits.beans.BeanConfig;
import com.moov.solutions.ribeits.model.exception.UtilsException;

public class JSonUtils <T>{
	
	Class clazz;
	ObjectMapper mapper = new ObjectMapper();
	DateFormat df = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss");
	
	public JSonUtils(Class clazz) {
		this.clazz = clazz;
		mapper.setDateFormat(df);
		
	}
	
	public String beanToJSon(T bean) throws UtilsException{		
		try {
			return mapper.writeValueAsString(bean);
		} catch (JsonProcessingException e) {
			throw new UtilsException("Error al convertir beanToJSon: " + e.getMessage());
		}		
	}
	
	public String beanToJSon(T bean, String datePattern) throws UtilsException{		
		try {
			
			SimpleDateFormat dateFormat = new SimpleDateFormat(datePattern);
			mapper.setDateFormat(dateFormat);
			
			return mapper.writeValueAsString(bean);
		} catch (JsonProcessingException e) {
			throw new UtilsException("Error al convertir beanToJSon: " + e.getMessage());
		}		
	}
	
	public String beanToJSon(T bean, String... fieldsOnlyIncluye ) throws UtilsException{		
		try {
		
			ObjectMapper mapper = new ObjectMapper();
			FilterProvider fp = JSonUtils.printOnlyArray("BeanFilterName", fieldsOnlyIncluye);
			return mapper.writer(fp).writeValueAsString(bean);
		
		} catch (JsonProcessingException e) {
			throw new UtilsException("Error al convertir beanToJSon: " + e.getMessage());
		}		
	}

	public String beanToJSon(T bean, String datePattern, String... fieldsOnlyIncluye ) throws UtilsException{		
		try {
		
			SimpleDateFormat dateFormat = new SimpleDateFormat(datePattern);
			mapper.setDateFormat(dateFormat);
			
			FilterProvider fp = JSonUtils.printOnlyArray("BeanFilterName", fieldsOnlyIncluye);
			return mapper.writer(fp).writeValueAsString(bean);
		
		} catch (JsonProcessingException e) {
			throw new UtilsException("Error al convertir beanToJSon: " + e.getMessage());
		}		
	}
	
	public String beanToJSonSpecific(T bean,String fieldsToJson) throws UtilsException{
		
		StringWriter writer = new StringWriter();
		try {
			JsonGenerator generator = new JsonFactory().createGenerator(writer);
			String[] fields = StringUtils.split(fieldsToJson, ',');
			
			generator.writeStartObject();
			
				for (int i = 0; i < fields.length; i++) {
					writeField(generator,fields[i],bean);
				}
				
			generator.writeEndObject();
			
			generator.close();
			return writer.toString();
			
			
		} catch (IOException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}
		return "";
	}
	
	/*
	 * DATE FORMAT
	 * 	@JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "dd/MM/yyyy HH:mm:ss")
	 * 	private Date date;
	 */
	
	public T JsonToBean(String json) throws UtilsException{		
		try {
			mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
			return (T) mapper.readValue(json, clazz);
		} catch (JsonProcessingException e) {
			throw new UtilsException("Error al convertir beanToJSon: " + e.getMessage());
		} catch (IOException e) {
			throw new UtilsException("Error al convertir beanToJSon: " + e.getMessage());
		}		
	}
	
	private void writeField(final JsonGenerator g, final String fieldName, T bean) throws IOException {
		Field field;
		try {
			field = clazz.getDeclaredField(fieldName);
			Annotation annotation = field.getAnnotation(BeanConfig.class);
			if (annotation != null) {
				field.setAccessible(true);

				BeanConfig beanConfig = (BeanConfig) annotation;

				Object value = field.get(bean);
				
				if (beanConfig.classType() == String.class) {
					if (value != null) {
						g.writeStringField(fieldName, (String) value);
					} else {
						g.writeStringField(fieldName, "");
					}
				}
				if (beanConfig.classType() == Integer.class) {
					if (value != null) {
						g.writeNumberField(fieldName, ((Integer) value).intValue());
					}else{
						g.writeNumberField(fieldName, 0);
					}
				}
				if (beanConfig.classType() == Double.class) {
					if (value != null) {
						g.writeNumberField(fieldName, (Double) value);
					} else {
						g.writeNumberField(fieldName, 0.0);
					}
				}
				if (beanConfig.classType() == Float.class) {
					if (value != null) {
						g.writeNumberField(fieldName, (Float) value);
					} else {
						g.writeNumberField(fieldName, 0.0);
					}
				}
				if (beanConfig.classType() == Boolean.class) {
					if (value != null) {
						g.writeBooleanField(fieldName, (Boolean) value);
					} else {
						g.writeBooleanField(fieldName, false);
					}
				}
				if (beanConfig.classType() == Date.class) {
					
					SimpleDateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss",new Locale("ES", "MX"));
					
					if (value != null) {
						g.writeStringField(fieldName, dateFormat.format((Date)value));
					} else {
						g.writeStringField(fieldName, "");
					}
				}


			}
		} catch (NoSuchFieldException | SecurityException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IllegalArgumentException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IllegalAccessException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

	}
	
	public static FilterProvider printOnlyArray(String filterName,String... values ){
		
		Set<String> printOnlyArray =  new HashSet<String>(Arrays.asList(values));
		SimpleBeanPropertyFilter filter = SimpleBeanPropertyFilter.serializeAll(printOnlyArray);
		FilterProvider fp = new SimpleFilterProvider().addFilter(filterName, filter);
		
		return fp;
	}
	
	public static FilterProvider excludeArray(String filterName,String... values ){
		
		Set<String> excludeArray =  new HashSet<String>(Arrays.asList(values));
		SimpleBeanPropertyFilter filter = SimpleBeanPropertyFilter.serializeAllExcept(excludeArray);
		FilterProvider fp = new SimpleFilterProvider().addFilter(filterName, filter);
		
		return fp;
	}
	
	
}

package omr.api.json;

import java.io.IOException;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.ser.FilterProvider;
import com.fasterxml.jackson.databind.ser.impl.SimpleBeanPropertyFilter;
import com.fasterxml.jackson.databind.ser.impl.SimpleFilterProvider;

import omr.api.exception.JSONException;

public class JSONUtils<T> {
	
	T t;
	
	public JSONUtils(T t) {
		this.t = t;
	}
	
	
	public String beanToJSON(Object bean) throws JSONException {
		String strJson = "";
		
		ObjectMapper mapper = new ObjectMapper();
		try {
			strJson = mapper.writeValueAsString(bean);
		} catch (JsonProcessingException e) {
			throw new JSONException("Error beanToSTring: " + e.getMessage());
		}
		
		return strJson;
	}
	
	public String beanToJSONFilterExclude(Object bean,String... filterFields) throws JSONException {
		String strJson = "";
		
		FilterProvider filterProvider = excludeArray("beanToJSONFilter", filterFields);
		
		ObjectMapper mapper = new ObjectMapper();
		try {
			strJson = mapper.writer(filterProvider).writeValueAsString(bean);
		} catch (JsonProcessingException e) {
			throw new JSONException("Error beanToSTring: " + e.getMessage());
		}
		
		return strJson;
	}
	
	public T JSONToBean(String strJson, Class<T> clazz) throws JSONException {
		T bean;
		
		ObjectMapper mapper = new ObjectMapper();
		try {
			bean = mapper.readValue(strJson,clazz);
		} catch (JsonProcessingException e) {
			throw new JSONException("Error JSONToBean JsonProcessingException: " + e.getMessage());
		} catch (IOException e) {
			throw new JSONException("Error JSONToBean IOException: " + e.getMessage());
		}
		
		return bean;
	}
	
	public static FilterProvider excludeArray(String filterName,String... values ){
		
		Set<String> excludeArray =  new HashSet<String>(Arrays.asList(values));
		SimpleBeanPropertyFilter filter = SimpleBeanPropertyFilter.serializeAllExcept(excludeArray);
		FilterProvider fp = new SimpleFilterProvider().addFilter(filterName, filter);
		
		return fp;
	}
	
	
}