Java Collections synchronizedSet() Method

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Description

The Java Collections synchronizedSet() method is used to return a synchronized (thread-safe) set backed by the specified set.

Declaration

Following is the declaration for java.util.Collections.synchronizedSet() method.

public static <T> Set<T> synchronizedSet(Set<T> s)

Parameters

s − This is the set to be "wrapped" in a synchronized set.

Return Value

• The method call returns a synchronized view of the specified set.

Exception

NA

Getting Synchronized Set From a Unsynchronized Set of Integer Example

The following example shows the usage of Java Collection synchronizedSet(Set) method. We've created a Set object of Integer. Few entries are added and then using synchronizedSet(Set) method, we've retrieved the synchronized version of set and printed the set.

package com.tutorialspoint;

import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

public class CollectionsDemo {
   public static void main(String[] args) {
      
      // create set
      Set<Integer> set = new HashSet<Integer>();

      // populate the set
      set.add(1); 
      set.add(2);
      set.add(3);

      // create a synchronized set
      Set<Integer> synset = Collections.synchronizedSet(set);

      System.out.println("Synchronized set is :"+synset);
   }
}

Output

Let us compile and run the above program, this will produce the following result.

Synchronized set is :[1, 2, 3]

Getting Synchronized Set From a Unsynchronized Set of String Example

The following example shows the usage of Java Collection synchronizedSet(Set) method. We've created a Set object of String and String. Few entries are added and then using synchronizedSet(Set) method, we've retrieved the synchronized version of map and printed the map.

package com.tutorialspoint;

import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

public class CollectionsDemo {
   public static void main(String[] args) {
      
      // create set
      Set<String> set = new HashSet<String>();

      // populate the set
      set.add("TP"); 
      set.add("IS");
      set.add("BEST");

      // create a synchronized set
      Set<String> synset = Collections.synchronizedSet(set);

      System.out.println("Synchronized set is :"+synset);
   }
}

Output

Let us compile and run the above program, this will produce the following result.

Synchronized set is :[IS, BEST, TP]

Getting Synchronized Set From a Unsynchronized Set of Object Example

The following example shows the usage of Java Collection synchronizedSet(Set) method. We've created a Set object of String and Student object. Few entries are added and then using synchronizedSet(Set) method, we've retrieved the synchronized version of map and printed the map.

package com.tutorialspoint;

import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

public class CollectionsDemo {
   public static void main(String[] args) {
      
      // create set
      Set<Student> set = new HashSet<Student>();

      // populate the set
      set.add(new Student(1, "Julie")); 
      set.add(new Student(2, "Robert"));
      set.add(new Student(3, "Adam"));

      // create a synchronized set
      Set<Student> synset = Collections.synchronizedSet(set);

      System.out.println("Synchronized set is :"+synset);
   }
}
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.

Synchronized set is :[[ 1, Julie ], [ 2, Robert ], [ 3, Adam ]]