Java Collections unmodifiableSortedMap() Method

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Description

The Java Collections unmodifiableSortedMap() method is used to return an unmodifiable view of the specified sorted map.

Declaration

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

public static <K,V> SortedMap<K,V> unmodifiableSortedMap(SortedMap<? extends K,? extends V> m)

Parameters

m − This is the sorted map for which an unmodifiable view is to be returned.

Return Value

• The method call returns an unmodifiable view of the specified sorted map.

Exception

NA

Getting Immutable SortedMap From a Mutable SortedMap of String,Integer Pair Example

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

package com.tutorialspoint;

import java.util.Collections;
import java.util.TreeMap;
import java.util.SortedMap;

public class CollectionsDemo {
   public static void main(String[] args) {
      
      // create map
      SortedMap<String,Integer> map = new TreeMap<String,Integer>();

      // populate the map
      map.put("1",1); 
      map.put("2",2);
      map.put("3",3);

      // create a sorted map
      SortedMap<String,Integer> sortedMap = Collections.unmodifiableSortedMap(map);

      System.out.println("Immutable Sorted map is :"+sortedMap);
   }
}

Output

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

Immutable Sorted map is :{1=1, 2=2, 3=3}

Getting Immutable SortedMap From a Mutable SortedMap of String,String Pair Example

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

package com.tutorialspoint;

import java.util.Collections;
import java.util.TreeMap;
import java.util.SortedMap;

public class CollectionsDemo {
   public static void main(String[] args) {
      
      // create map
      SortedMap<String,String> map = new TreeMap<String,String>();

      // populate the map
      map.put("1","TP"); 
      map.put("2","IS");
      map.put("3","BEST");

      // create a sorted map
      SortedMap<String,String> sortedMap = Collections.unmodifiableSortedMap(map);

      System.out.println("Immutable Sorted map is :"+sortedMap);
   }
}

Output

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

Immutable Sorted map is :{1=TP, 2=IS, 3=BEST}

Getting Immutable SortedMap From a Mutable SortedMap of String, Object Pair Example

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

package com.tutorialspoint;

import java.util.Collections;
import java.util.TreeMap;
import java.util.SortedMap;

public class CollectionsDemo {
   public static void main(String[] args) {
      
      // create map
      SortedMap<String,Student> map = new TreeMap<String,Student>();

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

      // create a sorted map
      SortedMap<String,Student> sortedMap = Collections.unmodifiableSortedMap(map);

      System.out.println("Immutable Sorted map is :"+sortedMap);
   }
}
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.

Immutable Sorted map is :{1=[ 1, Julie ], 2=[ 2, Robert ], 3=[ 3, Adam ]}