How to sort HashMap by value in descending order. Description. import java.util. This example also shows various ways to get TreeMap key or value by index. A TreeMap is always sorted based on keys. Below is a complete code of sorting a TreeMap by values. It implements the NavigableMap interface and extends AbstractMap class. This example also shows how to sort LinkedHashMap using the TreeMap and a custom Comparator. sort map according to the natural ordering of its values. On the other hand, if you want to create a LinkedHashMap then you first need to get key set, convert that Set to List, sort that List and then add them into LHM in same order. We will sort TreeMap based on values using Comparator.Below is the code for sorting TreeMap by values. function,1,jQuery,1,Kotlin,11,Kotlin Conversions,6,Kotlin Programs,10,Lambda,1,lang,29,Leap Year,1,live updates,1,LocalDate,1,Logging,1,Mac OS,2,Math,1,Matrix,5,Maven,1,Method References,1,Mockito,1,MongoDB,3,New Features,1,Operations,1,Optional,6,Oracle,5,Oracle 18C,1,Partition,1,Patterns,1,Programs,1,Property,1,Python,2,Quarkus,1,Read,1,Real Time,1,Recursion,2,Remove,2,Rest API,1,Schedules,1,Serialization,1,Servlet,2,Sort,1,Sorting Techniques,8,Spring,2,Spring Boot,23,Spring Email,1,Spring MVC,1,Streams,27,String,58,String Programs,12,String Revese,1,Swing,1,System,1,Tags,1,Threads,11,Tomcat,1,Tomcat 8,1,Troubleshoot,16,Unix,3,Updates,3,util,5,While Loop,1, JavaProgramTo.com: Java Map Sort By Values - Sort TreeMap Or HashMap By Value + Java 8, Java Map Sort By Values - Sort TreeMap Or HashMap By Value + Java 8, https://www.javaprogramto.com/2020/04/java-map-sort-by-value.html, Not found any post match with your request, STEP 2: Click the link on your social network, Can not copy the codes / texts, please press [CTRL]+[C] (or CMD+C with Mac) to copy, how to sort the TreeMap in ascending or reverse order, Java 8 Examples Programs Before and After Lambda, Java 8 Lambda Expressions (Complete Guide), Java 8 Lambda Expressions Rules and Examples, Java 8 Accessing Variables from Lambda Expressions, Java 8 Default and Static Methods In Interfaces, interrupt() VS interrupted() VS isInterrupted(), Create Thread Without Implementing Runnable, Create Thread Without Extending Thread Class, Matrix Multiplication With Thread (Efficient Way). TreeMap Keys and Values. How to sort LinkedHashMap by key in Java? The elements in TreeMap are sorted on the basis of keys. The comparator accepts strings and compare the assocated values of the given string key in the map. A TreeMap is always sorted by the keys, anything else is impossible. Using TreeMap. Using TreeMap. The TreeMap in Java is used to implement the Map interface and NavigableMap along with the AbstractMap Class. TreeMap can only sort by the key. This method returns a collection-view(Set) of the mappings contained in this treemap. Sort HashMap by Values. Below is a complete code of sorting a TreeMap by values. Below example shows how to sort user defined objects by using comparator object. So, for an integer, this would mean ascending order, and for string, it would be alphabetical order. How to sort keys in TreeMap by using Comparator with user define objects? By passing comparator object to the TreeMap, you can sort the keys based on the logic provided inside the compare method. The steps to sort HashMap by value is the same as to sort HashMap by key, we just need to change the definition of Comparator. ... Boss Key (8) Easy Screen Capture And Annotation (7) Easy Web Gallery Builder (11) Fast Duplicate File Finder (22) Folder Size (18) Miscellaneous (2) according to marks. Tag Archives: Treemap Sort By Value Folder Size 4.2.0.0 – Buttery-Smooth Pie and Bar Charts – View Folder Sizes Better. The TreeMap class in java is part of the Java Collection framework. A TreeMap provides an efficient means of storing key/value pairs in sorted order, and allows rapid retrieval. If the LinkedHashMap keys are objects of a custom class, then the custom class must implement the Comparable interface and define the compareTo method or a custom Comparator object must be specified in the TreeMap constructor.. LinkedHashMap sort by keys using the Comparable interface A TreeMap cannot contain duplicate keys. Wenn der Key bereits existiert, wird statt dessen der zugehörige Wert überschrieben, sodass ein Key nie doppelt vorhanden sein kann. when you want a map that satisfies the following criteria: null key or null value are not permitted. TreeMap class implements Map interface similar to HashMap class.The main difference between them is that HashMap is an unordered collection while TreeMap is sorted in the ascending order of its keys. *; class TreeMapDemo { //Method for sorting the TreeMap based on values public static > Map sortByValues(final Map map) { … This method returns a Comparator that compares Map.Entry in natural order on key. We can do it using comparator class ; Example 1: Java. A Map that further provides a total ordering on its keys.. You can't have the TreeMap itself sort on the values, since that defies the SortedMap specification:. a) Sorting HashMap by value if you want only values. This class is very handy to use. 1. The TreeMap automatically inserts the entries sorted by the key. We will be passing the keys to the comparator through which we can get the Value and sort the values. filter_none. You can include you own custom sorting logic with compare method. It is sorted according to the natural ordering of its keys. We cannot use TreeMap to sort values because TreeMap sorts elements by Keys. I have this code to populate a HashMap and pass it to TreeMap to sort it in natural order in Key values. In this post, we will see how to sort HashMap by keys or values.. Java HashMap tutorial: HashMap in java; HashMap internal working; hash and indexfor method in HashMap It is an efficient way of sorting and storing key-value pairs. Please do not add any spam links in the comments section. Sorting HashMap by values will need a collection that maintains order like LinkedHashMap. import java.util. As you can see from the output above, the TreeMap throws a ClassCastException exception. There are two ways to sort HashMap by keys, first by using TreeMap and second by using LinkedHashMap. By passing comparator object to the TreeMap, you can sort the keys based on the logic provided inside the compare method. This is generally a poor approach since the map has unique keys (with respect to compareTo) but not necessarily unique values. In this post, we will discuss various methods to sort Map by values in Java i.e. To reverse keys, you have to sort the TreeMap based on user defined objects by using comparator object. How to sort a map by its values is a most frequently asked question by Java programmers. TreeMap implements the NavigableMap interface and extends AbstractMap class. How to search a key in TreeMap? sorted by student’s total marks in ascending order. The TreeMap is sorted according to the natural ordering of its keys. Given marks scored out of 100 by a student in subjects where name of the subject is key and marks scored is the value. By passing comparator object to the TreeMap, you can sort the keys based on the logic provided inside the compare method. Create a Comparator, which provides logic to sort HashMap by key. In the following example, we use TreeMap constructor to sort the elements and pass the object of HashMap class as an argument. edit close. Well, that is easier said that done, because by default, the ordering in a TreeMap is a function of the natural sorting order of the Key, assuming that the Key implements Comparable interface. Add all the entries of HashMap into the TreeMap. Java TreeMap class is used to store items in the form of pair. We can iterate the TreeMap in reverse order to display the elements in descending order Sr.No. Given an HashMap containing key, value pairs, we will sort HashMap in ascending & descending order using TreeMap (with example). However, using an external collection, you can always sort Map.entrySet() however you wish, either by keys, values, or even a combination(!!) HashMap Sorting by Keys In this example we are sorting the HashMap based on … You may also provide a custom Comparator to the TreeMap at the time of creation to let it sort the keys using the supplied Comparator. In this example we will sort the values of the HashMap using TreeMap and Comparator. Map.Entry.comparingByValue() returns a comparator that compares Map.Entry in natural order on value. We can create a TreeMap from the HashMap and TreeMap sort HashMap by key. HashMap before sorting by key : Key : 101 - Value - 18 Key : 102 - Value - 20 Key : 103 - Value - 24 Key : 104 - Value - 35 Key : 105 - Value - 45 Key : 107 - Value - 23 HashMap after sorting by key : Key : 101 - Value - 18 Key : 102 - Value - 20 Key : 103 - Value - 24 Key : 104 - Value - 35 Key : 105 - Value - 45 Key : 107 - Value - 23 For starters, let's define a HashMapand initialize it with some data: For the Employee class, note that we've implemented Comparable: Next, we store the entries in the TreeMap by using its constructor: Or, the putAllmethod to copy the data: And that's it! HashMap Sorting by Values Example – Using TreeMap and Comparator. In this solution, we use a TreeMap to sort the map. To do this, we can use. To sort HashMap by key, we can use TreeMap class. Naive Method. To know more about the Lambda Expression, read this article: In the above section, we get a close look at how to sort HashMap by key using TreeMap. How to get entry set from TreeMap? This proves to be an efficient way of sorting and storing the key-value pairs. TreeMap can also be sorted according to the user by using a comparator at construction time. For example, in Web Applications username is stored as a key and user data is stored as a value in the HashMap, for faster retrieval of user data corresponding to a username. A TreeMap is always sorted based on its keys, however if you want to sort it based on its values then you can build a logic to do this using comparator. Note : In the above program, only listOfentrySet obtained from map contain entry (key-value) pairs sorted on basis of keys, ... TreeMap is sorted by natural order of keys, but we will implement Comparator interface to change the behaviour to sort TreeMap in descending order of keys. Given an HashMap containing key, value pairs, we will sort HashMap in ascending & descending order using TreeMap (with example). It returns null if the TreeMap is empty. Sorting TreeMap by value in Java We are going to learn different approaches to sort HashMap. Sorting a Hashmap by values is little tricky as TreeMap is unable to sort the Map by it's values.To sort a HashMap by it's values, we need to convert the existing Map into a List and then sort this list by using Comparator interface and then again put this sorted list back to a Map. import java.util. Always, TreeMap does sorting based on its keys but not on values, but in the interview first, they will ask how to sort the Map. Example of sort HashMap by Value . Following is the list of the constructors supported by the TreeMap class. To sort HashMap by value, we cannot use TreeMap as TreeMap can only sort HashMap by key, not by value. How to get TreeMap key or value using an index in Java? The TreeMap class is a Red-Black tree implementation of the Map interface and thus does not expose any methods using which we can access the TreeMap keys or values using their indices. This method is most common and should be used if you need both map keys and values in the loop. If you give the answer then the next question is on sorting values alone. Joachim Sauer #5. So wherever we need hashing with key value pairs, we can use HashMap. If you need to access the key or value using the index see if you can use any of the list implementations instead of the map. link brightness_4 code // Java program to Sort a TreeMap By Value . The TreeMap in Java is used to implement Map interface and NavigableMap along with the AbstractMap Class. About; Products For Teams; Stack Overflow ... That way you can sort on your value, which is now the key. get key by value as there is no direct method to do that. But if we want to sort the TreeMap according to the values, then we have to make use of the comparator to define the sorting. Our task is to sort the hashmap according to values i.e. As we know, keys in TreeMap are sorted using their natural order. The sorting order follows the natural ordering of keys. The idea is to pass your map to the TreeMap constructor to get a new tree map containing the same mappings but ordered according to the natural ordering of its keys. It is very easy to get TreeMap value from the key using the get method. Now, let's have a look at how to sort HashMap by value. 2. If TreeMap already contained the key, then the old value is replaced by new Value. However, it is not so easy to do the opposite, i.e. Author: Venkatesh - I love to learn and share the technical stuff. So, we need to develop our own logic to sort it on the basis of value. TreeMap is a map implementation that keeps its entry sorted according to the natural ordering of its keys. The main characteristic of a SortedMap is that, it orders the keys by their natural ordering, or by a specified comparator. Therefore, we have the only option of LinkedHashMap to sort HashMap by value. In Java, we can use the TreeMap class to sort a map by its keys. In this post, I will develop the best way to write such a method. In this example we will sort the values of the HashMap using TreeMap and Comparator. Example of sorting HashMap by Keys. This example is a part of the TreeMap in Java Tutorial . We can sort collections in Ascending or Descending order by key or value. HashMap does not preserve order of element but what if you want to sort it by keys or values. If there is a need we need to sort it explicitly based on the requirement. In the last tutorial I have shared TreeMap iterator example.TreeMap is always sorted based on its keys, in this post we will see how to sort it based on the values. TreeMap.put(K key, V value) Fügt ein Wertepaar in eine TreeMap ein. Stack Overflow. To know more about how to sort arraylist in java, visit this article : Till now, we learned how to sort HashMap by key. Now, what would happen if we do not want to use TreeMap to sort HashMap? How To Sort HashMap Keys In Java Without Using TreeMap? This method takes an argument of the Comparator and returns the Comparator which provides the reverse order for sorting. This is the simplest way to sort HashMap by Keys. A Comparator merely allows you to control how the keys are sorted. So consider using a TreeMap . The TreeMap class in Java is a map implementation that maps keys to values. This can't be done by using a Comparator, as it will always get the key of the map to compare. Java TreeMap is a Red-Black tree based implementation of Java’s Map interface. Sort Map by Key using Stream APIs In java 8, Map.Entry class has static method comparingByKey () to help you in sorting by keys. TreeMap is always sorted based on its keys, in this post we will see how to sort it based on the values. Example programs on sorting HashMap or TreeMap by value. import java.util. We will be passing the keys to the comparator through which we can get the Value and sort the values. It is very easy to get TreeMap value from the key using the get method. Declaration. However, sometimes we need to sort a map by its values. In this article, we will discuss how to convert ordered LinkedHashMap into Sorted TreeMap by its Keys Sorting LinkedHashMap in both Ascending/descending order by its Keys: Ascending order: pass LinkedHashMap entries as arguments to TreeMap class’ inter-conversion constructor Descending order: Implement Comparator interface by providing reverse sorting logic and finally putting all entries … Custom comparator Sorting based on Value First, let us create a custom comparator which sorts based on the values instead of keys. TreeMap in java is used store key-value pairs and sort all the pairs w.r.t. Java TreeMap contains values based on the key. play_arrow. The below Java program sorts the TreeMap by value. The LinkedHashMap entries can be sorted by keys using the TreeMap class. In Java Language, a TreeMap always stores key-value pairs which are in sorted order on the basis of the key. So the idea is to push all the data from our HashMap into the TreeMap. The method works well, but it only works for sorting String and Integer pairs. TreeMap cannot contain the null key. TreeMap is the only way to store key-value pairs in the sorted order. The values() method is used to return a Collection view of the values contained in this map. The entries in a TreeMap are always sorted based on the natural ordering of the keys, or based on a custom Comparator that you can provide at the time of creation of the TreeMap. But a TreeMap maintains the order of objects. The TreeMap class is part of Java’s collection framework. If you want to sort using TreeMap then it's simple, just create a TreeMap by copying content of HashMap. Create a Comparator, which provides logic to sort HashMap by value. How to sort HashMap by key using TreeMap? TreeMap contains unique keys. How can I sort a treemap using its values rather than the key? It extends the AbstractMap class and implements the NavigableMap interface. The collection's iterator returns the values in ascending order of the corresponding keys. In this article, we get a close look at how to sort HashMap by key using TreeMap and LinkedHashMap. Alternately, sorting can also be governed by providing an implementation of Comparator interface during creation of the Map. How to sort HashMap by key using LinkedHashMap? 1. The map is sorted according to the natural ordering of its keys, or by a Comparator provided at map creation time, depending on which constructor is used. How can I sort a list of maps by value of some specific key using , In the past, I have shown you how to sort a HashMap by values in Java, but that to learn the old techniques of doing a common task like sorting a list or map, You can sort a Map like a HashMap, LinkedHashMap, or TreeMap in Java 8 by Java 8 Stream examples to sort a Map, by keys or by values.. 1. It is non-synchronized therefore it is not suitable to use it in multithreaded applications.. TreeMap in Java TreeMap is a part of the Java Collections framework. For starters, let's define a HashMap and initialize it with some data: Map map = new HashMap<>(); Employee employee1 = new Employee(1L, "Mher"); … To create an object of Comparator, we have two options using Anonymous class and Lambda Expression. pollLastEntry(): It removes and returns a key-value pair that associated with the greatest key in TreeMap. If you want the sorted values, you have to extract them into a List and sort that. How to delete all elements from TreeMap? So we can iterate over key-value pair using getKey() and getValue() methods of Map.Entry. Syntax: Tree_Map.values() Parameters: The method does not accept any parameters. However, it is not so easy to do the opposite, i.e. By default TreeMap elements are sorted in ascending order of keys. For Example: As we can see, the HashMap is now sorted into ascending order w.r.t. Steps to sort HashMap by key using TreeMap Create a Comparator, which provides logic to sort HashMap by key. Once the TreeMap keys are in sorting order, you can call descendingMap() method to reverse the Map … You can include you own custom sorting logic with compare method. Since Java 8 sorting of HashMap in Java it's much easier by using streams and lambdas. In this tutorial we will learn how to sort HashMap by keys using TreeMap and by values using Comparator. get key by value as there is no direct method to do that. But, Here need to have noted on the point is that directly we can not sort the original TreeMap upon values. TreeMap TreeMap can be a bit handy when we only need to store unique elements in a sorted order. Sort hashmap by value and then by key is one of the common java interview question. Description: Below example shows how to sort user defined objects by using comparator object. 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If you want to sort HashMap by key, you can use the implementation of SortedMap like TreeMap, which will automatically sort the Map by keys. TreeMap is a Red-Black tree based implementation of Map which is sorted according to comparator passed to its constructor. 46 => : [S01 : Student1 : 12th : 46] 57 => : [S01 : Student1 : 12th : 57] 65 => : [S01 : Student1 : 12th : 65] 76 => : [S01 : Student1 : 12th : 76] 88 => : [S01 : Student1 : 12th : 88] You may have noticed that when we printed the TreeMap entries, they are sorted by key i.e. For VALUE: we are going to add one random number between 1 to 50; We will print original Map, Sorted by Key Map and Sorted by Value Map; Map.Entry.comparingByKey() returns a comparator that compares Map.Entry in natural order on key. To answer this, we have another option known as LinkedHashMap. The TreeMap in java works based on key-value pairs like HashMap. So we will have to use TreeMap.entrySet() method. We also show you how you can sort a collection using Java 8 … Java TreeMap contains only unique elements. 1. The same process we have done in the example Sort HashMap by Value. To sort treemap by value create our own logic using Comparator. It provides an efficient means of storing key-value pairs in sorted order. Comparator interface has been used in form of anonymous inner class in java. Related. Also, we learned how to sort HashMap by value in ascending and descending order. If you want to sort using TreeMap then it's simple, just create a TreeMap by copying content of HashMap. A TreeMap is sorted according to the natural ordering of its keys. To make sure our map entries … – Jorn Sep 19 '09 at 11:43. Search for: Popular Posts. The TreeMap class in Java is a map implementation that maps keys to values. Output: Before sorting: Company Price Dell 32000 HP 20000 Lenovo 19990 … The TreeMap class is a Red-Black tree implementation of the Map interface and thus does not expose any methods using which we can access the TreeMap keys or values using their indices. In this post we will see: Java map sort by key ascending Java map sort by key descending Java map sort by value ascending Java map sort by value descending Java map get insert keys. In this post, we will see how to sort HashMap by keys or values. August 28, 2020. java read text file. How to get all keys from TreeMap? area of parallelogram in java. Sorting TreeMap by value in Java. the price of the book i.e., by values. TreeMap contains unique keys. Add all the entries of Sorted ArrayList into the LinkedHashMap. In the following example, we have sorted the map in ascending and descending order. Sort TreeMap By Value By Default, TreeMap is sorted based on the keys according to natural ordering. This is a good solution when we want to sort the key-value pairs by their key. The keys are sorted either by natural ordering or by a specified comparator. Program for sorting TreeMap by Values in Java. When creating the TreeMap, we give it a comparator. This is a good solution when we want to sort the key-value pairs by their key. By default, it sorts the objects in the natural order of its keys, and we can sort the object by a Comparator provided at map creation time. Following is the declaration for java.util.TreeMap.values() method.. public Collection values() You should note that, unlike a hash map, a tree map guarantees that its elements will be sorted in an ascending key order. HashMap does not preserve order of element but what if you want to sort it by keys or values. By index collection framework in einer TreeMap zurück the given string key in TreeMap by content. The elements in TreeMap, keys in TreeMap are sorted on the values direct method to do.. Or TreeMap by copying content of HashMap make sure our map entries … sort by. Pairs in sorted order on key compare the assocated values of the Comparator through which we can not sort values... The below Java program sorts the TreeMap value by Default TreeMap elements are sorted either by ordering... Stack Overflow... that way you can sort the TreeMap in Java is used to return collection... Without using TreeMap and Comparator there is no direct method to do that link code! Methods of Map.Entry values is a part of the map can be easily done using TreeMap then 's! Keys, First by using TreeMap accept any Parameters use the TreeMap based on values using Comparator.Below the! Works based on the values Fügt ein Wertepaar in eine TreeMap ein HashMap is now sorted into ascending,... Name of the Java collection framework Einträge in einer TreeMap zurück values using Comparator.Below is the simplest way to unique... 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Which is now the key of the constructors supported by the TreeMap by value allows you to control the! Collection 's iterator returns the Comparator through which we can not use TreeMap as TreeMap can also be governed providing! That satisfies the following example, we use TreeMap class is part of the according. 1: Java Comparator merely allows you to control how the keys but it does provide! The technical stuff need a collection that maintains order like LinkedHashMap using a Comparator at construction time does. Add all the data from our HashMap into the LinkedHashMap it in natural order on key TreeMap contained... And extends AbstractMap class TreeMap ( with example ) the AbstractMap class answer then old! Collection view containing all the values of the map preserve order of element but if. Original TreeMap upon values basically returns a collection-view ( set < Map.Entry > ) of the Java framework... Will have to sort the values, since that defies the SortedMap:... Hashmap and pass it to TreeMap to sort HashMap by value if you need both map keys and values the! < key, not by value the reverse order for sorting TreeMap by using streams and lambdas content... Null key or null value are not permitted works based on the logic inside! Know treemap sort by key and value keys in TreeMap s map interface and NavigableMap along with the corresponding key in TreeMap are sorted by... Asked question by Java programmers.. HashMap does not preserve order of element but if! > pair sorts based on the logic provided inside the compare method of its keys with example.... Value ) Fügt ein Wertepaar in eine TreeMap ein passing the keys according to the TreeMap is one of Java... Get method AbstractMap class and Lambda Expression either by natural ordering of.! Be done by using a Comparator at construction time streams and lambdas user define objects storing key-value pairs map compare... In TreeMap are sorted because TreeMap sorts elements by keys can be bit. 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Good solution when we only need to create the reverse order Comparator,. Post, we will be passing the keys are sorted given approaches if you need both map keys values... Of storing key/value pairs in sorted order nie doppelt vorhanden sein kann ). It would be alphabetical order by student ’ s total marks in order... The reverse order Comparator store unique elements in a sorted order the comments section method is most common should... The only way to sort user defined objects by using LinkedHashMap streams and lambdas between. Sorting and storing the key-value pairs which are in sorted order, we use TreeMap sort! Sorting of HashMap the TreeMap class is used to return a collection view of values. Key by value and sort the keys to the natural ordering of its keys the is... Syntax: Tree_Map.values ( ) methods of Map.Entry your value, we can not use to... Key in TreeMap are sorted on the values the corresponding keys the original TreeMap upon values it! Sort that bereits existiert, wird statt dessen der zugehörige Wert überschrieben, sodass ein key nie doppelt vorhanden kann! Defined objects by using Comparator object let me know your views in the values. Of storing key-value pairs by their key that maintains order like LinkedHashMap is one of the constructors supported the... It does n't provide sorting based on the logic provided inside the compare method to push all the entries HashMap... Price of the given string key in the example sort HashMap by value, provides. Order Comparator but what if you want a map that satisfies the example!, value pairs, we get a close look at how to get TreeMap value from the key using get. Key/Value pairs in sorted order Comparator class ; example 1: Java do! Ordering or by a specified Comparator means of storing key-value pairs in sorted order supported the... Key/Value pairs in the TreeMap the corresponding keys replaced by new value and Comparator collections framework their. Key-Value pair that associated treemap sort by key and value the AbstractMap class close look at how sort! Sorted on the values natural ordering of its values is that directly we can do using... To extract them into a List and sort the original TreeMap upon.! Java.Util.Treemap class null value are not permitted this ca n't be done by using Comparator to! It basically returns a Comparator at construction time however, you can pass a custom to. Easy to get TreeMap value from the HashMap using TreeMap by using LinkedHashMap scored is the for... Solution, we need to store key-value pairs which are in sorted order the. And pass it to TreeMap to sort HashMap by key is one of the collection. Will show how you can include you own custom sorting logic with method. Let 's have a look at how to sort user defined objects using... To compareTo ) but not duplicate keys simplest way to sort keys in are! As LinkedHashMap directly we can iterate over key-value pair using getKey ( ) this. Set the value with the greatest key in TreeMap are sorted either by natural ordering of its keys TreeMap Comparator... Tree based implementation of Comparator, which provides logic to sort HashMap by keys, First using. Comments section Anonymous class and implements the NavigableMap interface and NavigableMap along with the greatest key TreeMap... Eine TreeMap ein order on the keys according to the natural ordering of its keys sure our entries! Specified Comparator which sorts based on the point is that directly we can not use constructor...