使用Comparator实现自定义排序

package map;

/**
 * Created by benjamin on 11/5/15.
 */
public class Person {
    String firstName,lastName;
    char sex;
    Integer age;

    public Person(String firstName, String lastName, char sex, Integer age) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.sex = sex;
        this.age = age;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public char getSex() {
        return sex;
    }

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

    public Integer getAge() {
        return age;
    }

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

package map;

/**
 * Created by benjamin on 11/5/15.
 */


import java.util.Comparator;

/**
 * 谁的拼音靠前,谁就排前面.
 * 然后对名字进行排序.如果同名,女性排前面.
 * 如果名字和性别都相同,年龄小的排前面.
 *
 *
 * int compare(Object o1, Object o2)返回一个基本的数据类型
 * 如果要按照升序排序
 * 则o1 < o2, return -1; equals return 0;  o1 > 02 return 1;
 * 如果要按照降序排序
 * 则01 < 02, return 1;  equals return 0;  o1 > o2 return -1;
 *
 */
public class Comparators {
    /**
     * 获取合适的比较器
     * @return
     */
    public static Comparator getComparator() {
        return new Comparator() {
            @Override
            public int compare(Object o1, Object o2) {
                if(o1 instanceof String) {
                    return compare((String)o1, (String)o2);
                } else if(o1 instanceof Integer) {
                    return compare((Integer)o1, (Integer)o2);
                } else if(o1 instanceof Person) {
                    return comparePerson((Person) o1, (Person) o2);
                } else {
                    System.out.println("未找到合适的比较器");
                    return 1;
                }
            }
        };
    }

    private static int compare(String o1, String o2) {
        int len1 = o1.length();
        int len2 = o2.length();
        int min = Math.min(len1, len2);
        char v1[] = o1.toCharArray();
        char v2[] = o2.toCharArray();
        int pos = 0;
        //循环得到名字的排序
        while(--min != 0) {
            char c1 = v1[pos];
            char c2 = v2[pos];
            if (c1 != c2) {
                return c1 - c2;
            }
            pos ++;
        }
        return len1 - len2;
    }

    /**
     * 比较年龄
     * @param o1
     * @param o2
     * @return
     */
    private static int compare(Integer o1, Integer o2) {
        int val1 = o1.intValue();
        int val2 = o2.intValue();
        return val1 < val2 ? -1 : (val1 == val2 ? 0 : 1);
    }

    /**
     * 比较性别
     * @param o1
     * @param o2
     * @return
     */
    private static int compare(char o1, char o2) {
        return ((o1 == o2) ? 0 : (o1 == '男' ? 1 : -1));
    }

    /**
     * 比较Person
     * @param o1
     * @param o2
     * @return
     */
    private static int comparePerson(Person o1, Person o2) {
        String firstName1 = o1.getFirstName();
        String firstName2 = o2.getFirstName();
        String lastName1 = o1.getLastName();
        String lastName2 = o2.getLastName();
        char sex1 = o1.getSex();
        char sex2 = o2.getSex();
        Integer age1 = o1.getAge();
        Integer age2 = o2.getAge();
        return (compare(firstName1, firstName2) == 0 ?
                (compare(lastName1, lastName2) == 0 ?
                (compare(sex1, sex2) == 0 ?
                (compare(age1, age2) == 0 ? 0 :
                compare(age1, age2)) :
                compare(sex1, sex2)) :
                compare(lastName1, lastName2)) :
                compare(firstName1, firstName2));
    }

}

package map;

import java.util.Arrays;

/**
 * Created by benjamin on 11/5/15.
 */
public class ComparatorsTest {
    public static void main(String[] args) {
        Person[] person = new Person[]{
                new Person("ouyang", "feng", '男', new Integer(27)),
                new Person("zhuang", "gw", '男', new Integer(27)),
                new Person("deng", "jx", '男', new Integer(28)),
                new Person("deng", "jx", '女', new Integer(27))
        };

        for (Person p : person) {
            System.out.println("排序前=" + p.getFirstName() + " " + p.getLastName() + " " + p.getSex() + " " + p.getAge());
        }
        Arrays.sort(person, Comparators.getComparator());
        System.out.println("----------------------------------------------------");

        for (Person p : person) {
            System.out.println("排序前=" + p.getFirstName() + " " + p.getLastName() + " " + p.getSex() + " " + p.getAge());
        }
    }
}

排序前=ouyang feng 男 27
排序前=zhuang gw 男 27
排序前=deng jx 男 28
排序前=deng jx 女 27

----------------------------------------------------
排序前=deng jx 女 27
排序前=deng jx 男 28
排序前=ouyang feng 男 27
排序前=zhuang gw 男 27