{"id":2169,"date":"2020-08-24T13:35:17","date_gmt":"2020-08-24T05:35:17","guid":{"rendered":"http:\/\/127.0.0.2\/?p=2169"},"modified":"2020-08-24T13:36:02","modified_gmt":"2020-08-24T05:36:02","slug":"2020java%e6%95%99%e7%a8%8b%ef%bc%9a%e9%9b%86%e5%90%88%e6%a1%86%e6%9e%b6%e4%b9%8bset%e9%9b%86%e5%90%88","status":"publish","type":"post","link":"https:\/\/www.9713job.com\/?p=2169","title":{"rendered":"2020java\u6559\u7a0b\uff1a\u96c6\u5408\u6846\u67b6\u4e4bSet\u96c6\u5408"},"content":{"rendered":"

\u96c6\u5408\u6846\u67b6\u4e4bSet\u96c6\u5408<\/h3>\n

Set\u5b50\u63a5\u53e3
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\n\u65b9\u6cd5\uff1a\u5168\u90e8\u7ee7\u627f\u81eaCollection\u4e2d\u7684\u65b9\u6cd5<\/p>\n

Set\u5b9e\u73b0\u7c7b
\nHashSet
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\n\u5f53\u5b58\u5165\u5143\u7d20\u7684\u54c8\u5e0c\u7801\u76f8\u540c\u65f6\uff0c\u4f1a\u8c03\u7528equals\u8fdb\u884c\u786e\u8ba4\uff0c\u5982\u7ed3\u679c\u4e3atrue\uff0c\u5219\u62d2\u7edd\u540e\u8005\u5b58\u5165<\/p>\n

import java.util.HashSet;\r\nimport java.util.Objects;\r\n\r\npublic class demos{\r\n    public static void main(String[] args) {\r\n        Student s1=new Student(\"tom\",22,\"\u7537\",99D);\r\n        Student s2=new Student(\"jack\",23,\"\u5973\",78.5);\r\n        Student s3=new Student(\"home\",44,\"\u7537\",46.5);\r\n        Student s4=new Student(\"home\",44,\"\u7537\",46.5);\r\n        HashSet<Student> set=new HashSet<Student>();\r\n        set.add(s1);\r\n        set.add(s2);\r\n        set.add(s3);\r\n        set.add(s4);\r\n        for(Student s:set){\r\n            System.out.println(s);\r\n        }\r\n    }\r\n}\r\nclass Student{\r\n    String name;\r\n    Integer age;\r\n    String sex;\r\n    Double score;\r\n    public Student(String name, Integer age, String sex, Double score) {\r\n        this.name = name;\r\n        this.age = age;\r\n        this.sex = sex;\r\n        this.score = score;\r\n    }\r\n\r\n    @Override\r\n    public boolean equals(Object o) {\r\n        if (this == o) return true;\r\n        if (o == null || getClass() != o.getClass()) return false;\r\n        Student student = (Student) o;\r\n        return Objects.equals(name, student.name) &&\r\n                Objects.equals(age, student.age) &&\r\n                Objects.equals(sex, student.sex) &&\r\n                Objects.equals(score, student.score);\r\n    }\r\n\r\n    @Override\r\n    public int hashCode() {\r\n        return Objects.hash(name, age, sex, score);\r\n    }\r\n\r\n    @Override\r\n    public String toString() {\r\n        return \"Student{\" +\r\n                \"name='\" + name + '\\'' +\r\n                \", age=\" + age +\r\n                \", sex='\" + sex + '\\'' +\r\n                \", score=\" + score +\r\n                '}';\r\n    }\r\n}<\/pre>\n
LinkedHashSet:
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TreeSet\uff1a
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\n\u5b9e\u73b0\u4e86SortedSet\u63a5\u53e3\uff0c\u5bf9\u96c6\u5408\u5143\u7d20\u81ea\u52a8\u6392\u5e8f
\n\u5143\u7d20\u5bf9\u8c61\u7684\u7c7b\u578b\u5fc5\u987b\u5b9e\u73b0Comparable\u63a5\u53e3\uff0c\u6307\u5b9a\u6392\u5e8f\u89c4\u5219
\n\u901a\u8fc7ComparaTo\u65b9\u6cd5\u786e\u5b9a\u662f\u5426\u4e3a\u91cd\u590d\u5143\u7d20<\/p>\n
import java.util.*;\r\n\r\npublic class demos{\r\n    public static void main(String[] args) {\r\n        TreeSet<Teacher> list= new TreeSet<Teacher>();\r\n        list.add(new Teacher(\"tom\",22,\"\u7537\",5000D));\r\n        list.add(new Teacher(\"tom2\",24,\"\u7537\",5000D));\r\n        list.add(new Teacher(\"tom3\",23,\"\u5973\",5000D));\r\n        list.add(new Teacher(\"tom\",22,\"\u7537\",5000D));\r\n        for(Teacher t:list){\r\n            System.out.println(t);\r\n        }\r\n    }\r\n}\r\nclass Teacher implements Comparable<Teacher>{\r\n    String name;\r\n    Integer age;\r\n    String sex;\r\n    Double salary;\r\n    public Teacher(String name, Integer age, String sex, Double salary) {\r\n        this.name = name;\r\n        this.age = age;\r\n        this.sex = sex;\r\n        this.salary = salary;\r\n    }\r\n    @Override\r\n    public String toString() {\r\n        return \"Teacher{\" +\r\n                \"name='\" + name + '\\'' +\r\n                \", age=\" + age +\r\n                \", sex='\" + sex + '\\'' +\r\n                \", salary=\" + salary +\r\n                '}';\r\n    }\r\n    @Override\r\n    public boolean equals(Object o) {\r\n        if (this == o) return true;\r\n        if (o == null || getClass() != o.getClass()) return false;\r\n        Teacher teacher = (Teacher) o;\r\n        return Objects.equals(name, teacher.name) &&\r\n                Objects.equals(age, teacher.age) &&\r\n                Objects.equals(sex, teacher.sex) &&\r\n                Objects.equals(salary, teacher.salary);\r\n    }\r\n\r\n    @Override\r\n    public int hashCode() {\r\n        return Objects.hash(name, age, sex, salary);\r\n    }\r\n    @Override\r\n    public int compareTo(Teacher o) {\r\n        if(this.salary>o.salary){\r\n            return 1;\r\n        }else if(this.salary<o.salary){\r\n            return -1;\r\n        }else{\r\n            if(this.age>o.age){\r\n                return 1;\r\n            }else if(this.age<o.age){\r\n                return -1;\r\n            }else{\r\n                if(this.name.compareTo(o.name)<0){\r\n                    return -1;\r\n                }else if(this.name.compareTo(o.name)>0){\r\n                    return 1;\r\n                }else{\r\n                    return this.sex.compareTo(o.sex);\r\n                }\r\n            }\r\n        }\r\n    }\r\n}<\/pre>\n","protected":false},"excerpt":{"rendered":"
\u96c6\u5408\u6846\u67b6\u4e4bSet\u96c6\u5408 Set\u5b50\u63a5\u53e3 \u7279\u70b9\uff1a\u65e0\u5e8f\u3001\u65e0\u4e0b\u6807\uff0c\u5143\u7d20\u4e0d\u53ef\u91cd\u590d \u65b9\u6cd5\uff1a\u5168\u90e8\u7ee7\u627f\u81eaCollection\u4e2d\u7684 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[],"class_list":["post-2169","post","type-post","status-publish","format-standard","hentry"],"_links":{"self":[{"href":"https:\/\/www.9713job.com\/index.php?rest_route=\/wp\/v2\/posts\/2169","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.9713job.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.9713job.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.9713job.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.9713job.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2169"}],"version-history":[{"count":2,"href":"https:\/\/www.9713job.com\/index.php?rest_route=\/wp\/v2\/posts\/2169\/revisions"}],"predecessor-version":[{"id":2171,"href":"https:\/\/www.9713job.com\/index.php?rest_route=\/wp\/v2\/posts\/2169\/revisions\/2171"}],"wp:attachment":[{"href":"https:\/\/www.9713job.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2169"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.9713job.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2169"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.9713job.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2169"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}