package com.kmall.common.utils;

import java.io.IOException;
import java.io.StringWriter;

import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

/**
 * bean转json格式或者json转bean格式, 项目中我们通常使用这个工具类进行json---java互相转化
 */
public class JacksonUtil {
    private static ObjectMapper mapper = new ObjectMapper();

    public static String bean2Json(Object obj) throws IOException {
        StringWriter sw = new StringWriter();
        JsonGenerator gen = new JsonFactory().createJsonGenerator(sw);
        mapper.writeValue(gen, obj);
        gen.close();
        return sw.toString();
    }

    public static <T> T json2Bean(String jsonStr, Class<T> objClass)
            throws JsonParseException, JsonMappingException, IOException {
        return mapper.readValue(jsonStr, objClass);
    }
}