IdentityHashMap类equals()方法 (IdentityHashMap Class equals() method)

• equals() method is available in java.util package.

  equals()方法在java.util包中可用。

• equals() method is used to check whether this IdentityHashMap object and the given object (ob) are equals or not.

  equals()方法用于检查此IdentityHashMap对象和给定对象(ob)是否相等。

• equals() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.

  equals()方法是一种非静态方法，仅可通过类对象访问，如果尝试使用类名访问该方法，则会收到错误消息。

• equals() method does not throw an exception at the time of checking the equality of two objects.

  在检查两个对象的相等性时， equals()方法不会引发异常。

Syntax:

句法：

    public boolean equals(Object ob);

Parameter(s):

参数：

• Object ob – represents the object to be checked for equality with this IdenityHashMap.

  对象ob –表示要与此IdenityHashMap进行相等性检查的对象。

Return value:

返回值：

The return type of the method is Set, it returns true when this IdentityHashMap and the given object are same otherwise it returns false.

方法的返回类型为Set ，如果此IdentityHashMap和给定的对象相同，则返回true，否则返回false。

Example:

例：

// Java program to demonstrate the example 
// of equals(Object ob) method of IdentityHashMap 
import java.util.*;
public class EqualsOfIdentityHashMap {
public static void main(String[] args) {
// Instantiates a IdentityHashMap object
Map < Integer, String > map1 = new IdentityHashMap < Integer, String > ();
Map < Integer, String > map2 = new IdentityHashMap < Integer, String > ();
// By using put() method is to add
// key-value pairs in a IdentityHashMap
// map1
map1.put(10, "C");
map1.put(20, "C++");
map1.put(50, "JAVA");
map1.put(40, "PHP");
map1.put(30, "SFDC");
// By using put() method is to add
// key-value pairs in a IdentityHashMap
// map2
map2.put(10, "SQL");
map2.put(20, "DBMS");
// Display IdentityHashMap
System.out.println("map1: " + map1);
System.out.println("map2: " + map2);
// By using using equals() method is to
// compare two object for equality check
boolean status = map1.equals(map2);
// Display status
System.out.print("map1.equals(map2): " + status);
}
}

Output

输出量

map1: {20=C++, 40=PHP, 50=JAVA, 30=SFDC, 10=C}
map2: {20=DBMS, 10=SQL}
map1.equals(map2): false

翻译自: https://www.includehelp.com/java/identityhashmap-equals-method-with-example.aspx