- Java.util Package Classes
- Java.util - Home
- Java.util - ArrayDeque
- Java.util - ArrayList
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- Java.util - BitSet
- Java.util - Calendar
- Java.util - Collections
- Java.util - Currency
- Java.util - Date
- Java.util - Dictionary
- Java.util - EnumMap
- Java.util - EnumSet
- Java.util - Formatter
- Java.util - GregorianCalendar
- Java.util - HashMap
- Java.util - HashSet
- Java.util - Hashtable
- Java.util - IdentityHashMap
- Java.util - LinkedHashMap
- Java.util - LinkedHashSet
- Java.util - LinkedList
- Java.util - ListResourceBundle
- Java.util - Locale
- Java.util - Observable
- Java.util - PriorityQueue
- Java.util - Properties
- Java.util - PropertyPermission
- Java.util - PropertyResourceBundle
- Java.util - Random
- Java.util - ResourceBundle
- Java.util - ResourceBundle.Control
- Java.util - Scanner
- Java.util - ServiceLoader
- Java.util - SimpleTimeZone
- Java.util - Stack
- Java.util - StringTokenizer
- Java.util - Timer
- Java.util - TimerTask
- Java.util - TimeZone
- Java.util - TreeMap
- Java.util - TreeSet
- Java.util - UUID
- Java.util - Vector
- Java.util - WeakHashMap
- Java.util Package Extras
- Java.util - Interfaces
- Java.util - Exceptions
- Java.util - Enumerations
- Java.util Useful Resources
- Java.util - Useful Resources
- Java.util - Discussion
Java IdentityHashMap equals() Method
Description
The Java IdentityHashMap equals(Object o) method is used to compare the specified object with this map for equality.
Declaration
Following is the declaration for java.util.IdentityHashMap.equals() method.
public boolean equals(Object o)
Parameters
o − This is the object to be compared for equality with this map.
Return Value
The method call returns 'true' if the specified object is equal to this map.
Exception
NA
Checking Equality of IdentityHashMap Objects of Integer, Integer Pair Example
The following example shows the usage of Java IdentityHashMap equals() method to check if map objects are same or not. We've created two Map objects of Integer,Integer pairs. Then few entries are added, maps are compared using equals() method.
package com.tutorialspoint; import java.util.IdentityHashMap; public class IdentityHashMapDemo { public static void main(String args[]) { // create identity map IdentityHashMap<Integer,Integer> newmap = new IdentityHashMap<>(); IdentityHashMap<Integer,Integer> newmap2 = new IdentityHashMap<>(); // populate identity map newmap.put(1, 1); newmap.put(2, 2); newmap.put(3, 3); // populate identity map newmap2.put(1, 4); newmap2.put(2, 5); newmap2.put(3, 6); System.out.println("Maps are equal: " + newmap.equals(newmap2)); } }
Output
Let us compile and run the above program, this will produce the following result.
Maps are equal: false
Checking Equality of IdentityHashMap Objects of Integer, String Pair Example
The following example shows the usage of Java IdentityHashMap equals() method to check if map objects are same or not. We've created two Map objects of Integer,String pairs. Then few entries are added, maps are compared using equals() method.
package com.tutorialspoint; import java.util.IdentityHashMap; public class IdentityHashMapDemo { public static void main(String args[]) { // create map IdentityHashMap<Integer,String> newmap = new IdentityHashMap<>(); IdentityHashMap<Integer,String> newmap2 = new IdentityHashMap<>(); // populate map newmap.put(1, "tutorials"); newmap.put(2, "point"); newmap.put(3, "is best"); // populate map newmap2.put(1, "A"); newmap2.put(2, "B"); newmap2.put(3, "C"); System.out.println("Maps are equal: " + newmap.equals(newmap2)); } }
Output
Let us compile and run the above program, this will produce the following result.
Maps are equal: false
Checking Equality of IdentityHashMap Objects of Integer, Object Pair Example
The following example shows the usage of Java IdentityHashMap equals() method to check if map objects are same or not. We've created two Map objects of Integer,Student pairs. Then few entries are added, maps are compared using equals() method.
package com.tutorialspoint; import java.util.IdentityHashMap; public class IdentityHashMapDemo { public static void main(String args[]) { // create map IdentityHashMap<Integer,Student> newmap = new IdentityHashMap<>(); IdentityHashMap<Integer,Student> newmap2 = new IdentityHashMap<>(); // populate map newmap.put(1, new Student(1, "Julie")); newmap.put(2, new Student(2, "Robert")); newmap.put(3, new Student(3, "Adam")); // populate map newmap2.put(1, new Student(1, "Julie")); newmap2.put(2, new Student(2, "Robert")); newmap2.put(3, new Student(4, "Jene")); System.out.println("Maps are equal: " + newmap.equals(newmap2)); } } class Student { int rollNo; String name; Student(int rollNo, String name){ this.rollNo = rollNo; this.name = name; } @Override public String toString() { return "[ " + this.rollNo + ", " + this.name + " ]"; } }
Output
Let us compile and run the above program, this will produce the following result.
Maps are equal: false