使用Java代码对多个字段属性去重，并返回所有字段

Oracle去重多个字段，并返回其他所有字段

业务场景：

业务需求1：需要对前端入参进行某个字段或者多个字段去重操作，防止插入重复数据。

业务需求2：多条件下抓取数据列表，需要对数据列表的某个字段或者多个字段进行去重。

例子：

对学生的姓名、年龄去重

public static class Student implements Serializable {
        private String name;
        private String age;

        private String sex;

        public Student(String name, String age, String sex) {
            this.name = name;
            this.age = age;
            this.sex = sex;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public String getAge() {
            return age;
        }

        public void setAge(String age) {
            this.age = age;
        }

        public String getSex() {
            return sex;
        }

        public void setSex(String sex) {
            this.sex = sex;
        }

        @Override
        public String toString() {
            return "Student{" +
                    "name='" + name + '\'' +
                    ", age='" + age + '\'' +
                    ", sex='" + sex + '\'' +
                    '}';
        }
    }

解决方案：

public static void main(String[] args) {
        Student student1 = new Student("11","11","0");
        Student student2 = new Student("11","22","1");
        Student student3 = new Student("11","22","0");
        Student student4 = new Student("11","33","1");
        Student student5 = new Student("22","33","0");

        List<Student> students = new ArrayList<Student>();
        students.add(student1);
        students.add(student2);
        students.add(student3);
        students.add(student4);
        students.add(student5);
        System.out.println("--------------------对象去重-----------------------");
        List<Student> collect = students.stream().distinct().collect(toList());
        for (Student student : collect) {
            System.out.println(student);
        }
        System.out.println("-------------------根据多个字段去重--------------------------");
        ArrayList<Student> collect1 = students.stream().collect(Collectors.collectingAndThen(Collectors.toCollection(() -> new TreeSet<>(
                Comparator.comparing(student -> student.getName() + student.getAge())
        )), ArrayList::new));
        for (Student student : collect1) {
            System.out.println(student);
        }

    }

输出结果集：

Tip:使用了Java8获取字段的方式，比较常用，类似前端的钩子函数，可读性比较明了，但是当你检测哪个字段被哪里地方被引用时，这样写的字段不会被检测到。