Java List转字符串，Set转字符串，集合转字符串，数组转集合

逃离我推掉我的手 2021-09-24 12:34 920阅读 0赞

集合转字符串 ：

Set<String> set1 = new HashSet<>();
            set1.add("a");
            set1.add("b");
            System.out.println(StringUtils.join(set1.toArray(), ","));//a,b
    
            List<String> list1 = new ArrayList<>();
            System.out.println(StringUtils.join(list1.toArray(), ","));//
    
            list1.add("c");
            list1.add("d");
            System.out.println(StringUtils.join(list1.toArray(), ","));//c,d

数组转集合：

//org.apache.commons.lang3
            Set<String> shopIdSet = new HashSet<>();
            String s1 = StringUtils.join(shopIdSet.toArray(), ",");
            System.out.println(s1);//""
    
            shopIdSet.add("1");
            shopIdSet.add("2");
            s1 = StringUtils.join(shopIdSet.toArray(), ",");
            System.out.println(s1);//1,2
            
            String[] array = new String[]{"a", "b", "a"};
            System.out.println(new HashSet<>(Arrays.asList(array)));//[a, b]

工具类：

package org.apache.commons.lang3;
    
    import java.io.UnsupportedEncodingException;
    import java.nio.charset.Charset;
    import java.text.Normalizer;
    import java.text.Normalizer.Form;
    import java.util.ArrayList;
    import java.util.Arrays;
    import java.util.Iterator;
    import java.util.List;
    import java.util.Locale;
    import java.util.Objects;
    import java.util.regex.Pattern;
    
    public class StringUtils {
    .............
    
    }

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