使用Comparator实现自定义排序

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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;    }}

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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));    }

}

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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());        }    }}

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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