封装JsonUtils工具类

Posted 2022-05-28 cqming

import java.util.List;

import com.fasterxml.jackson.core.JsonProcessingException;
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();

    /**
     * 将对象转换成json字符串。
     * <p>Title: pojoToJson</p>
     * <p>Description: </p>
     * @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> T jsonToPojo(String jsonData, Class<T> 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
     * <p>Title: jsonToList</p>
     * <p>Description: </p>
     * @param jsonData
     * @param beanType
     * @return
     */
    public static <T>List<T> jsonToList(String jsonData, Class<T> beanType) 
    	JavaType javaType = MAPPER.getTypeFactory().constructParametricType(List.class, beanType);
    	try 
    		List<T> list = MAPPER.readValue(jsonData, javaType);
    		return list;
		 catch (Exception e) 
			e.printStackTrace();
		
    	
    	return null;