浅述数组排序

javascript

数组自带的函数sort可以根据自定义的排序器排序

function compare(v1, v2) {
	return v1-v2;
} 
var values = [4,1,2,5,3];
var vv = values.sort(compare);
console.info(vv);

java

如果有一个复杂数据类型的集合需要排序时，处理方式有两种

用Comparator定义一个比较器

1. 定义一个Person类

public class Person {

	private String name;

	private int age;

	public Person(String name, int age) {
		super();
		this.name = name;
		this.age = age;
	}

	public Person() {
		super();
	}

	public String getName() {
		return name;
	}

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

	public int getAge() {
		return age;
	}

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

2. 定义比较器

public class PersonComparator implements Comparator<Person> {

	@Override
	public int compare(Person o1, Person o2) {
		return o1.getAge() - o2.getAge();
	}
}

3. 排序

List<Person> list = new ArrayList<Person>();
Collections.sort(list, new PersonComparator());

复杂数据类继承Comprable 重写比较方法

1. 复杂数据类重写compareTo(O)

public class Person implements Comparable<Person>{

	private String name;

	private int age;

	public Person(String name, int age) {
		super();
		this.name = name;
		this.age = age;
	}

	public Person() {
		super();
	}

	public String getName() {
		return name;
	}

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

	public int getAge() {
		return age;
	}

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

	@Override
	public int compareTo(Person o) {
		return o.getAge()-this.getAge();
	}
}

2. 排序

List<Person> list = new ArrayList<Person>();
Collections.sort(list);