Map的key转小写后转驼峰再转换成实体类

转换的工具方法,只需把他们放入Util工具类中,或自己的类中即可使用;

    
    private Object mapToObject(Map<String, Object> map, Class<?> beanClass) throws Exception {
		if (map == null)
			return null;

		String json=JSONUtils.toJSONString(toReplaceKeyLow(map));
		return JSONArray.parseObject(json, beanClass);
	}
	public static String underlineToCamel2(String param){
    	param = param.toLowerCase();//此处为全部转小写,方便根据_判定后一位转驼峰
        if (param==null||"".equals(param.trim())){
            return "";
        }
        //使用正则表达式
        StringBuilder sb=new StringBuilder(param);
        Matcher mc= Pattern.compile("_").matcher(param);
        int i=0;
        while (mc.find()){
            int position=mc.end()-(i++);
            //String.valueOf(Character.toUpperCase(sb.charAt(position)));
            sb.replace(position-1,position+1,sb.substring(position,position+1).toUpperCase());
        }
        return sb.toString();
    }
    public static Map<String, Object> toReplaceKeyLow(Map<String, Object> map) {
        Map re_map = new HashMap();
        if(re_map != null) {
            Iterator var2 = map.entrySet().iterator();

            while(var2.hasNext()) {
                Entry<String, Object> entry = (Entry)var2.next();
                re_map.put(underlineToCamel2((String)entry.getKey()), map.get(entry.getKey()));
            }

            map.clear();
        }

        return re_map;
    }

调用的例子,

List reslist = null;
//query的结构是List<Map<String,Object>()>()
//TemplateAttachedRelation是一个实体类
for (int i = 0; i < query.size(); i++) {
		reslist.add((TemplateAttachedRelation) mapToObject((Map<String, Object>) query.get(i), TemplateAttachedRelation.class ));
		}

Map转驼峰

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class CamelAndlineUtils {
	public static void main(String[] args) {
        String str = "{'user_name':'ok','user_sex':0,object_info':{'business_code':'0001','object_info2':{'object_1':'ok'}}}";
        String strs[] = str.split(":");
        /*for (String is : strs) {
        	System.out.println(is);
        }*/
        StringBuilder sb = new StringBuilder();
        for (String o : strs) {
        	String _tmp[]  = o.split(",");
        	if(_tmp.length > 1){
        		//替换数组2的值为驼峰
        		sb.append(_tmp[0]).append(",").append(underlineToCamel2(_tmp[1]));
        	}else{
        		//替换''里的数值为驼峰
        		sb.append(underlineToCamel2(_tmp[0]));
        	}
        	
        	sb.append(":");
        }
        
        String str2 = "{'userName':'ok','userSex':0,objectInfo':{'businessCode':'0001','objectInfo2':{'object1':'ok'}}}";
        String strs2[] = str2.split(":");
        /*for (String is : strs) {
            System.out.println(is);
        }*/
        StringBuilder sb2 = new StringBuilder();
        for (String o : strs) {
            String _tmp[]  = o.split(",");
            if(_tmp.length > 1){
                //替换数组2的值为驼峰
                sb2.append(_tmp[0]).append(",").append(camelToUnderline(_tmp[1]));
            }else{
                //替换''里的数值为驼峰
                sb2.append(camelToUnderline(_tmp[0]));
            }

            sb2.append(":");
        }
        System.out.println(sb.substring(0,sb.length() - 1).toString());
        System.out.println(sb2.substring(0,sb2.length() - 1).toString());

        Map mymap = new HashMap<>();
        mymap.put("userName", "zhangsan");
        mymap.put("USER_ID", "zhangsan");
        mymap.put("USER_AGE", "zhangsan");
        mymap.put("USER_HHHH", "zhangsan");
        mymap.put("USER_NAEE", "zhangsan");
        Map replaceKeyLow = new HashMap<>();
        replaceKeyLow = toReplaceKeyLow(mymap);
        replaceKeyLow = null;
    }


    public static final char UNDERLINE='_';
    public static String camelToUnderline(String param){
        if (param==null||"".equals(param.trim())){
            return "";
        }
        int len=param.length();
        StringBuilder sb=new StringBuilder(len);
        for (int i = 0; i < len; i++) {
            char c=param.charAt(i);
            if (Character.isUpperCase(c)){
                sb.append(UNDERLINE);
                sb.append(Character.toLowerCase(c));
            }else{
                sb.append(c);
            }
        }
        return sb.toString();
    }
    public static String underlineToCamel(String param){
    	param = param.toLowerCase();
        if (param==null||"".equals(param.trim())){
            return "";
        }
        int len=param.length();
        StringBuilder sb=new StringBuilder(len);
        for (int i = 0; i < len; i++) {
            char c=param.charAt(i);
            if (c==UNDERLINE){
                if (++i<len){
                    sb.append(Character.toUpperCase(param.charAt(i)));
                }
            }else{
                sb.append(c);
            }
        }
        return sb.toString();
    }
    public static String underlineToCamel2(String param){
    	param = param.toLowerCase();
        if (param==null||"".equals(param.trim())){
            return "";
        }
        StringBuilder sb=new StringBuilder(param);
        Matcher mc= Pattern.compile("_").matcher(param);
        int i=0;
        while (mc.find()){
            int position=mc.end()-(i++);
            //String.valueOf(Character.toUpperCase(sb.charAt(position)));
            sb.replace(position-1,position+1,sb.substring(position,position+1).toUpperCase());
        }
        return sb.toString();
    }
    public static Map<String, Object> toReplaceKeyLow(Map<String, Object> map) {
        Map re_map = new HashMap();
        if(re_map != null) {
            Iterator var2 = map.entrySet().iterator();

            while(var2.hasNext()) {
                Entry<String, Object> entry = (Entry)var2.next();
                re_map.put(underlineToCamel2((String)entry.getKey()), map.get(entry.getKey()));
            }

            map.clear();
        }

        return re_map;
    }
}
原文地址:https://www.cnblogs.com/himonkey/p/9702649.html