Comparatorcan be used if you want to compare objects based on certain attributes/fields. For example, 2 persons can be compared based on `height` or `age` etc. (this can not be done using comparable.) The method
MyComparator实现了Comparator的compare 方法 因为其他的类包含了排序的逻辑,所以我们需要提供了Comparator 的实现了给Collections.sort 方法,例如Collections.sort(empList, new MyComparator()); Comparator 的实现类可以给我们提供了扩展其他排序的能力,因为这个时候你可以选择使用Comparable 的自然排序或者是Comparator 提供...
To use the Comparator interface, the class has to implement the method compare(). It can be used to compare two objects in a way that might not align with the natural order of the object. For example, import java.io.*; import java.lang.*; import java.util.*; class Employee { int ...
Using Comparator Unlike Comparable, Comparator is external to the element type we are comparing. It’s a separate class. We create multiple separate classes (that implement Comparator) to compare by different members. Collections class has a second sort() method and it takes Comparator. The sort(...
import java.util.Comparator; public class Employee implements Comparable<Employee> { private int id; private String name; private int age; private long salary; public int getId() { return id; } public String getName() { return name;
Comparable接口和Comparator接口 二者都是Java集合框架的成员 其中Collection接口和Map接口的子接口和实现类如下: (1)Comparable接口:默认比较规则 Comparable和Comparator两种比较器的区别 Comparable接口的类如何比较,则依赖compareTo方法的实现,compareTo方法也被称为自然比较方法。如果开发者add进入一个Collection的对象想要...
When working with custom types, or trying to compare objects that aren’t directly comparable, we need to make use of a comparison strategy. We can build one simply by making use of theComparatororComparableinterfaces. 2. Setting Up the Example ...
The basic difference between the Comparable and Comparator is that the Comparable interface provides the single sorting sequence whereas the Comparator interface provides the multiple sorting sequences.
For example, to sort in a reverse order, you can implement a comparison method that reverses the outcome of a comparison. The equals() Method The equals() method, shown here, tests whether an object equals the invoking comparator − boolean equals(Object obj) obj is the object to be ...
mahdihp / Comparable Star 1 Code Issues Pull requests java comparable comparator javase Updated Aug 29, 2018 Java Load more… Improve this page Add a description, image, and links to the comparable topic page so that developers can more easily learn about it. Curate this topic Add ...