Java 8 中Map转成对象-Toy模板网

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功能：

1. HashMap＜Object,Object＞转成对象 AlertDeviceInfo

2 List＜HashMap＜Object,Object＞＞转为 List＜AlertDeviceInfo>

核心代码：

package com.whm.bigdata;

import cn.hutool.json.JSONUtil;
import com.fasterxml.jackson.core.type.TypeReference;
import lombok.extern.slf4j.Slf4j;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.stream.Collectors;

@Slf4j
public class testA {
    public static void main(String[] args) {
        List<HashMap<Object, Object>> list = new ArrayList<>();
        HashMap<Object, Object> map = new HashMap<>();
        map.put("devUid", 201);
        map.put("devLogIds", Arrays.asList("1"));
        map.put("devAttackResult", 1);
        map.put("vendor", "sangfor");
        map.put("productVer", "AF8.0.1");
        map.put("originProductType", "SIP");
        map.put("originProductVer", "SIP5.0.58");
        map.put("deviceId", "HGFEDCBA");
        map.put("productType", "AF");
        map.put("manage", "ABCDEFGH");
        map.put("devLogCount", 10);
        list.add(map);

        List<AlertDeviceInfo> hostInfos = list.stream()
                .map(entity -> JSONUtil.toBean(JSONUtil.parseObj(entity), AlertDeviceInfo.class)).collect(Collectors.toList());
        log.info("--list: {}", hostInfos);

        System.out.println(get(list));

        AlertDeviceInfo alertDeviceInfo = JSONUtil.toBean(JSONUtil.parseObj(map), AlertDeviceInfo.class);
        log.info("--map: {}", alertDeviceInfo);

    }

    private static List<AlertDeviceInfo> get(Object object) {
        List<AlertDeviceInfo> alertDeviceInfos = new ArrayList<>();
        try {
            alertDeviceInfos = JsonUtil.getObjectMapper().convertValue(
                    object,
                    new TypeReference<List<AlertDeviceInfo>>() {
                    }
            );
        } catch (Exception e) {
            System.out.println("转换错误");
        }
        return alertDeviceInfos;
    }
}

工具包

package com.whm.bigdata;

import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;

import javax.validation.constraints.NotNull;

public class JsonUtil {

    private static ObjectMapper OBJECT_MAPPER;

    private JsonUtil() {
    }

    @NotNull
    public static ObjectMapper getObjectMapper() {
        if (OBJECT_MAPPER == null) {
            ObjectMapper localObjectMapper = new ObjectMapper();
            localObjectMapper.enable(new JsonParser.Feature[]{JsonParser.Feature.ALLOW_COMMENTS});
            localObjectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
            localObjectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
            OBJECT_MAPPER = localObjectMapper;
        }

        return OBJECT_MAPPER;
    }
}

实体类，如果要控制输出属性，就展示要输出的，比如上面11个属性，只要2个，写一个输出对象，就只有2个属性的，我这根据有个需求，不同公司返回该对象的不同字段展示

package com.whm.bigdata;

import com.fasterxml.jackson.annotation.JsonProperty;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.util.List;

@AllArgsConstructor
@NoArgsConstructor
@Data
public class AlertDeviceInfo {
    private String deviceId;

    private String manage;

//    private String originProductType;
//
//    private String originProductVer;
//
//    private String vendor;
//
//    private String productType;
//
//    private String productVer;
//
//    @JsonProperty("devUId")
//    private Integer devUid;
//
//    private List<String> devLogIds;
//
//    private Integer devLogCount;
//
//    private Integer devAttackResult;
}

JSON + JAVA 8 Stream处理该问题文章来源地址https://www.toymoban.com/news/detail-660219.html

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