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  • 一行代码实现java list去重

    1.不带类型写法:

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    List listWithoutDup = new ArrayList(new HashSet(listWithDup));

    2.带类型写法(以String类型为例):
    1)Java 7以下写法:

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    List<string> listWithoutDup = new ArrayList<string>(new HashSet<string>(listWithDup));</string></string></string>

    2)Java 7及以上写法:

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    List<string> listWithoutDup = new ArrayList<>(new HashSet<>(listWithDup));</string>


    样例:

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    import java.util.ArrayList;
    import java.util.HashSet;
    import java.util.List;
     
    public class Test {
        public static void main(String[] args) {
            List<string> listWithDup = new ArrayList<string>();
            listWithDup.add("1");
            listWithDup.add("2");
            listWithDup.add("3");
            listWithDup.add("1");
     
            List<string> listWithoutDup = new ArrayList<string>(new HashSet<string>(listWithDup));
            System.out.println("list with dup:"+ listWithDup);
            System.out.println("list without dup:"+ listWithoutDup);
        }
    }</string></string></string></string></string>

    样例运行结果: list with dup:[1, 2, 3, 1]
    list without dup:[3, 2, 1]

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  • 原文地址:https://www.cnblogs.com/likeju/p/5072075.html
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