建议直接学习google的guava包了，里面提供了强大的流畅风格比较器。

下面是个例子。更多你可以看http://ifeve.com/google-guava-ordering/

 import com.google.common.base.Function;
import com.google.common.collect.Lists;
import com.google.common.collect.Ordering;

import java.util.List;

/**
 * Created by leeyee.li on 2015/9/20.
 */
public class OrderTest {

    public static final Ordering<Student> ORDER_BY_GRADE = Ordering.natural().onResultOf(new Function<Student, Comparable>() {
        @Override
        public Comparable apply(Student input) {
            return input.grade;
        }
    });

    public static void main(String[] args) {
        List<Student> students = Lists.newArrayList(
                new Student("001", 90),
                new Student("002", 97),
                new Student("003", 95)
        );
        System.out.println("排序前：" + students);
        System.out.println("顺序排序后：" + ORDER_BY_GRADE.sortedCopy(students));
        System.out.println("倒序排序后：" + ORDER_BY_GRADE.reverse().sortedCopy(students));
        System.out.println("最小对象：" + ORDER_BY_GRADE.min(students));
        System.out.println("最大对象：" + ORDER_BY_GRADE.max(students));
    }

}

class Student {
    String sno;
    Integer grade;

    public Student() {
    }

    public Student(String sno, Integer grade) {
        this.sno = sno;
        this.grade = grade;
    }

    public String getSno() {
        return sno;
    }

    public void setSno(String sno) {
        this.sno = sno;
    }

    public Integer getGrade() {
        return grade;
    }

    public void setGrade(Integer grade) {
        this.grade = grade;
    }

    @Override
    public String toString() {
        final StringBuilder sb = new StringBuilder("Student{");
        sb.append("sno='").append(sno).append('\'');
        sb.append(", grade=").append(grade);
        sb.append('}');
        return sb.toString();
    }
}

JAVA 菜鸟 问一个菜鸟问题 list 的排序问题

AlgoChen

8个回复

JAVA 菜鸟问一个菜鸟问题 list 的排序问题