StringUtils

Posted 2020-12-15 f-society

package com.intfish.util;

/**
 *
 */

import org.apache.commons.lang3.StringEscapeUtils;
import org.apache.commons.lang3.text.StrBuilder;

import java.io.UnsupportedEncodingException;
import java.text.NumberFormat;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;


public class StringUtils extends org.apache.commons.lang3.StringUtils {

    /**
     * 替换掉html标签方法
     */
    public static String stripHtml(String html) {
        if (isBlank(html)){
            return "";
        }
        String regEx = "<.+?>";
        Pattern p = Pattern.compile(regEx);
        Matcher m = p.matcher(html);
        String s = m.replaceAll("");
        return s;
    }

    /**
     * 缩略字符串（不区分中英文字符）
     * @param str 目标字符串
     * @param length 截取长度
     * @return
     */
    public static String abbr(String str, int length) {
        if (str == null) {
            return "";
        }
        try {
            StringBuilder sb = new StringBuilder();
            int currentLength = 0;
            for (char c : stripHtml(StringEscapeUtils.unescapeHtml4(str)).toCharArray()) {
                currentLength += String.valueOf(c).getBytes("GBK").length;
                if (currentLength <= length - 3) {
                    sb.append(c);
                } else {
                    sb.append("...");
                    break;
                }
            }
            return sb.toString();
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return "";
    }



    /**空字符串*/
    private static final String NULLSTR = "";

    /**
     * 获取参数不为空
     * @param value
     * @param defaultValue
     * @param <T>
     * @return
     */
    public static <T> T nvl(T value,T defaultValue){
        return value !=null ? value : defaultValue;
    }

    /**
     * 判断一个对象是否为空
     * @param object
     * @return true为空 false为非空
     */
    public static boolean isNull(Object object){
        return object == null;
    }

    /**
     * 判断一个对象为非空
     * @param object
     * @return true:空  false：非空
     */
    public static boolean isNotNUll(Object object){
        return !isNull(object);
    }

    /**
     * 判断一个Collection是否为空，包含List,Set,Queue
     * @param coll
     * @return true:为空,false：非空
     */
    public static boolean isEmpty(Collection<?> coll){
        return isNull(coll) || coll.isEmpty();
    }

    /**
     * 判断一个Collection是否非空
     * @param coll
     * @return true:非空 false：空
     */
    public static boolean isNotEmpty(Collection<?> coll){
        return !isEmpty(coll);
    }

    /**
     * 判断一个对象数组是否为空
     * @param objects
     * @return true:为空,false：非空
     */
    public static boolean isEmpty(Object[] objects){
        return isNull(objects) || objects.length==0;
    }

    /**
     * 判断一个对象数组为非空
     * @param objects
     * @return true:非空 false：空
     */
    public static boolean isNotEmpty(Object[] objects){
        return !isEmpty(objects);
    }

    /**
     * 判断一个Map 是否为空
     * @param map
     * @return rue:为空,false：非空
     */
    public static boolean isEmpty(Map<?,?> map){
        return isNull(map) || map.isEmpty();
    }

    /**
     * 判断一个Map是否非空
     * @param map
     * @return true:非空 false：空
     */
    public static boolean isNotEmpty(Map<?,?> map){
        return !isEmpty(map);
    }

    /**
     * 判断一个字符串是否为空
     * @param str
     * @return true:非空 false：空
     */
    public static boolean isEmpty(String str){
        return isNull(str) || NULLSTR.equals(str.trim());
    }

    /**
     * 判断一个字符串为非空
     * @param str
     * @return true：非空 false：空
     */
    public static boolean isNotEmpty(String str){
        return !isEmpty(str);
    }


    public static boolean isEmpty(Object obj){
        return obj == null || "".equals(obj);
    }

    public static boolean isNotEmpty(Object obj){
        return !isEmpty(obj);
    }

    /**
     * 判断一个对象是否是数组类型
     * @param object
     * @return true：是数组 false：不是数组
     */
//    public static boolean isArray(Object object){
//        return isNotNUll(object) && object.getClass().isArray();
//    }

    /**
     * 去字符串头尾空格
     * @param str
     * @return
     */
    public static String trim(String str){
        return str == null ? "" : str.trim();
    }

    /**
     * 截取字符串
     * @param str
     * @param start
     * @param end
     * @return
     */
    public static String substring(final String str,int start,int end){
        if (str == null){
            return NULLSTR;
        }
        if (end < 0){
            end = str.length() + end;
        }
        if (start < 0 ){
            start = str.length() + start;
        }
        if (end > str.length()){
            end = str.length();
        }
        if (start > end){
            return NULLSTR;
        }
        if (start < 0){
            start = 0;
        }
        if (end < 0){
            end = 0;
        }
        return str.substring(start,end);
    }

    /**
     * 字符串首字母小写
     * @param str
     * @return
     */
    public static String uncapitalize(String str){
        int strLen;
        if (str == null || (strLen = str.length()) == 0){
            return str;
        }
        return new StrBuilder(strLen).append(Character.toLowerCase(str.charAt(0))).append(str.substring(1)).toString();
    }

    /**
     * 判断是否包含字符串
     * @param str
     * @param strs
     * @return
     */
    public static boolean inStringIgnoreCase(String str,String... strs){
        if (str != null && strs != null){
            for(String s : strs){
                if (str.equalsIgnoreCase(trim(s))){
                    return true;
                }
            }
        }
        return false;
    }

    /**
     * 将带下划线的字符串转换为驼峰形式 如 hello_world -> HelloWorld,HELLO_WORLD -> HelloWorld
     * @param name
     * @return
     */
    public static String convertToCamelCase(String name){
        StringBuilder result = new StringBuilder();
        //如果字符串为空，没必要转换
        if (name == null || isEmpty(name)){
            return "";
            //如果字符串不包含下划线，仅首字母大写
        }else if (!name.contains("_")){
            return name.substring(0,1).toUpperCase() + name.substring(1).toLowerCase();
        }

        //使用“_”分割字符串
        String[] camels = name.split("_");
        for (String camel : camels){
            //跳过字符串开头中间结尾的下划线，以及双下划线
            if (camel.isEmpty()){
                continue;
            }
            //首字母大写
            result.append(camel.substring(0,1).toUpperCase());
            result.append(camel.substring(1).toLowerCase());
        }
        return result.toString();
    }

    /**
     * 字符串数据处理
     * @param value
     * @return
     */
    public static String valueAsStr(Object value){
        if (value instanceof String){
            return (String) value;
        }
        if (value != null){
            return value.toString();
        }else {
            return null;
        }
    }

    /**
     * 整型数据处理
     */
    public static Integer valueAsInt(Object value){
        if (value instanceof Integer){
            return (Integer) value;
        }else if (value instanceof Number){
            return ((Number)value).intValue();
        }else if (value instanceof String){
            if ("NaN".equals(value)){
                return null;
            }
            return Integer.valueOf((String) value);
        }else if (value instanceof Boolean){
            return ((Boolean)value) ? 1 : 0;
        }
        else {
            return null;
        }
    }

    public static String  getStringJoinedValue(CharSequence delimiter, Iterable<? extends CharSequence> elements){
        String str = "";
        if (null != elements ){
            str += String.join(delimiter,elements);
        }
        return str;

    }

    public static List<String> doubleListToStringList(List<Double> data){
        if(data!=null && data.size()>0){
            NumberFormat nf = NumberFormat.getInstance();
            nf.setGroupingUsed(false);
            return data.stream().map(nf::format).collect(Collectors.toList());
        }
        return new ArrayList<>();
    }

    /**
     * 将key,value按splitChar分割封装成map
     * @param key "channelid,islogin"
     * @param value "vivo,yes"
     * @param splitChar 分割符
     * @author wangxiaolei
     * @date 2020/4/15 19:15
     * @return java.util.Map<java.lang.String,java.lang.Object>  {"channelid":"vivo", "islogin","yes"}
     */
    public static Map<String,Object> splitToMap(String key, String value, String splitChar){
        Map<String, Object> resultMap = new LinkedHashMap<>();
        if(!StringUtils.isEmpty(key)){
            String[] k = key.split(splitChar);
            String[] v = value.split(splitChar);
            for (int i = 0; i < k.length; i++) {
                resultMap.put(k[i], v[i]);
            }
        }
        return resultMap;
    }

    /**
     * 将 字符串 value 根据splitChar为分割符，在第n个位置切成为两段。如 n=1, "a,b,c,d" => ["a","b,c,d"]
     * @param value 字符串
     * @param n 前n个
     * @param splitChar 分割符
     * @author wangxiaolei
     * @date 2020/4/15 20:50
     * @return java.util.List<java.lang.String> 返回长度为2的list
     */
    public static List<String> splitTopN(String value, int n, String splitChar){
        List<String> result = new ArrayList<>();
        if(!StringUtils.isEmpty(value)){
            String[] vs = value.split(splitChar);
            List<String> a = new ArrayList<>();
            List<String> b = new ArrayList<>();
            int min = Math.min(vs.length, n);
            int i = 0;
            for(i = 0;i < min; i++){
                a.add(vs[i]);
            }
            for(;i < vs.length; i++){
                b.add(vs[i]);
            }
            result.add(String.join(splitChar,a));
            result.add(String.join(splitChar,b));
        }
        while(result.size() < 2){
            result.add("");
        }
        return result;
    }

    /**
     * 将map的字段合并成string类型  {"a":1},{"b",2}  ==>  a:1,b:2
     * @param list
     * @return
     */
    public static String mapToFieldValue(List<Map<String, Object>> list){
        StringBuilder sb = new StringBuilder();
        if(!StringUtils.isEmpty(list)){
            for (Map<String, Object> stringObjectMap : list) {
                for (Map.Entry<String, Object> entry : stringObjectMap.entrySet()) {
                    String key = entry.getKey();
                    Object value = entry.getValue();
                    sb.append(key).append(":").append(value).append(",");
                }
            }
        }
        String str = sb.toString();
        if(str.endsWith(",")) {
            return str.substring(0, str.length() - 1);  //去掉最后面的 ","
        }
        return str;
    }

}