Json反序列化对象通用工具类

 

 

一、json需要依赖的包

 

 

jackson.version可以参考地址：http://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core

 

	com.fasterxml.jackson.core
	jackson-core
	${jackson.version}


	com.fasterxml.jackson.core
	jackson-annotations
	${jackson.version}


	com.fasterxml.jackson.core
	jackson-databind
	${jackson.version}

 

 

 

二、json反序列化工具类

 

 

 

import java.io.IOException;
import java.util.List;
import java.util.Map;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;

public class JsonUtils {

	// 定义jackson对象
	private static final ObjectMapper MAPPER = new ObjectMapper();
	static {
		// 忽略JSON中没有的字段，防止反序列化对象的时候报找不到属性字段的异常
		MAPPER.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
		// 如果json字符串中含有新行时，加上这个
		MAPPER.configure(JsonParser.Feature.ALLOW_UNQUOTED_CONTROL_CHARS, true);
		//空值转换异常
		MAPPER.configure(JsonParser.Feature.ALLOW_COMMENTS, true) ;   
	}

	/**
	 * 将对象转换成json字符串。
	 * 

	 * Title: pojoToJson
	 * 
	 * 

	 * Description:
	 * 
	 * 
	 * @param data
	 * @return
	 */
	public static String objectToJson(Object data) {
		try {
			String string = MAPPER.writeValueAsString(data);
			return string;
		} catch (JsonProcessingException e) {
			e.printStackTrace();
		}
		return null;
	}

	/**
	 * 将json结果集转化为对象
	 * 
	 * @param jsonData
	 *            json数据
	 * @param clazz
	 *            对象中的object类型
	 * @return
	 */
	public static  T jsonToPojo(String jsonData, Class beanType) {
		try {
			T t = MAPPER.readValue(jsonData, beanType);
			return t;
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}

	/**
	 * 将json数据转换成pojo对象list
	 * 

	 * Title: jsonToList
	 * 
	 * 

	 * Description:
	 * 
	 * 
	 * @param jsonData
	 * @param beanType
	 * @return
	 */
	public static  List jsonToList(String jsonData, Class beanType) {
		JavaType javaType = MAPPER.getTypeFactory().constructParametricType(List.class, beanType);
		try {
			List list = MAPPER.readValue(jsonData, javaType);
			return list;
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
	}

    /**
     * json字符串转Map集合
     * @param jsonStr
     * @return
     * @throws IOException
     */
    @SuppressWarnings("unchecked")
    public static Map parseMap(String jsonStr) throws IOException {
        Map map = MAPPER.readValue(jsonStr, Map.class);
        return map;
    }

    /**
     * json字符串转List集合
     * @param jsonStr
     * @return
     * @throws IOException
     */
    public static List parseList(String jsonStr) throws IOException {
        return MAPPER.readValue(jsonStr, new TypeReference>() {});
    }
}