Java IdentityHashMap equals()方法

Java中的java.util.IdentityHashMap.equals()方法用于检查两个地图之间是否相等。它验证作为参数传递的一个地图的元素是否与这个地图的元素相等。

语法

ihashmap1.equals(ihashmap2)

参数： 该方法接受一个身份哈希图类型的参数ihashmap2，指的是要与该哈希图进行平等检查的地图。

返回值： 如果两个对象地图的平等性都成立，该方法返回真，否则返回假。

下面的程序说明了java.util.IdentityHashMap.equals()方法的工作：

程序1 :

// Java code to illustrate the equals() method
import java.util.*;
  
public class Identity_Hash_Map_Demo {
    public static void main(String[] args)
    {
  
        // Creating an empty IdentityHashMap
        IdentityHashMap<Integer, String> identity_hash1 = 
                   new IdentityHashMap<Integer, String>();
        IdentityHashMap<Integer, String> identity_hash2 = 
                   new IdentityHashMap<Integer, String>();
  
        // Mapping string values to int keys
        identity_hash1.put(10, "Geeks");
        identity_hash1.put(15, "4");
        identity_hash1.put(20, "Geeks");
        identity_hash1.put(25, "Welcomes");
        identity_hash1.put(30, "You");
          
        // Mapping string values to int keys
        identity_hash2.put(10, "Geeks");
        identity_hash2.put(15, "4");
        identity_hash2.put(20, "Geeks");
        identity_hash2.put(25, "Welcomes");
        identity_hash2.put(30, "You");
  
        // Displaying the IdentityHashMap
        System.out.println("First Map: "
                        + identity_hash1);
  
        // Displaying the final IdentityHashMap
        System.out.println("Second Map: "
                        + identity_hash2);
                          
        // Displaying the equality
        System.out.println("Equality: "+
                  identity_hash1.equals(identity_hash2));
    }
}

输出:

First Map: {10=Geeks, 30=You, 20=Geeks, 25=Welcomes, 15=4}
Second Map: {10=Geeks, 30=You, 20=Geeks, 25=Welcomes, 15=4}
Equality: true

示例2

// Java code to illustrate the equals() method
import java.util.*;
  
public class Identity_Hash_Map_Demo {
    public static void main(String[] args)
    {
  
        // Creating an empty IdentityHashMap
        IdentityHashMap<Integer, String> identity_hash1 = 
                   new IdentityHashMap<Integer, String>();
        IdentityHashMap<Integer, String> identity_hash2 = 
                   new IdentityHashMap<Integer, String>();
  
        // Mapping string values to int keys
        identity_hash1.put(10, "Geeks");
        identity_hash1.put(15, "4");
        identity_hash1.put(20, "Geeks");
        identity_hash1.put(25, "Welcomes");
        identity_hash1.put(30, "You");
          
        // Mapping string values to int keys
        identity_hash2.put(10, "Geeks");
        identity_hash2.put(15, "4");
        identity_hash2.put(20, "Geek");
        identity_hash2.put(25, "Welcomes");
        identity_hash2.put(30, "You");
  
        // Displaying the IdentityHashMap
        System.out.println("First Map: "
                        + identity_hash1);
  
        // Displaying the final IdentityHashMap
        System.out.println("Second Map: "
                        + identity_hash2);
                          
        // Displaying the equality
        System.out.println("Equality: "+
                  identity_hash1.equals(identity_hash2));
    }
}

输出:

First Map: {10=Geeks, 30=You, 20=Geeks, 25=Welcomes, 15=4}
Second Map: {10=Geeks, 30=You, 20=Geek, 25=Welcomes, 15=4}
Equality: false