Discussions
Categories
- 196.9K All Categories
- 2.2K Data
- 239 Big Data Appliance
- 1.9K Data Science
- 450.3K Databases
- 221.7K General Database Discussions
- 3.8K Java and JavaScript in the Database
- 31 Multilingual Engine
- 550 MySQL Community Space
- 478 NoSQL Database
- 7.9K Oracle Database Express Edition (XE)
- 3K ORDS, SODA & JSON in the Database
- 545 SQLcl
- 4K SQL Developer Data Modeler
- 187K SQL & PL/SQL
- 21.3K SQL Developer
- 295.9K Development
- 17 Developer Projects
- 138 Programming Languages
- 292.6K Development Tools
- 107 DevOps
- 3.1K QA/Testing
- 646K Java
- 28 Java Learning Subscription
- 37K Database Connectivity
- 155 Java Community Process
- 105 Java 25
- 22.1K Java APIs
- 138.1K Java Development Tools
- 165.3K Java EE (Java Enterprise Edition)
- 18 Java Essentials
- 160 Java 8 Questions
- 86K Java Programming
- 80 Java Puzzle Ball
- 65.1K New To Java
- 1.7K Training / Learning / Certification
- 13.8K Java HotSpot Virtual Machine
- 94.3K Java SE
- 13.8K Java Security
- 204 Java User Groups
- 24 JavaScript - Nashorn
- Programs
- 440 LiveLabs
- 38 Workshops
- 10.2K Software
- 6.7K Berkeley DB Family
- 3.5K JHeadstart
- 5.7K Other Languages
- 2.3K Chinese
- 171 Deutsche Oracle Community
- 1.1K Español
- 1.9K Japanese
- 232 Portuguese
Retrieve last element in the Map

Hi,
I have Map which contains 5 elements, I want to iterate retrieve only the last element in the Map, how I can get the last element in the loop?
Thanks
Answers
-
I have Map which contains 5 elements, I want to iterate retrieve only the last element in the Map, how I can get the last element in the loop?
What was YOUR answer to that interview question? Did they say you were right? Post the answer you gave and tell us all about the interview: the types of questions ask, the responses you got, etc.
I would have simply ask them: what does 'last element' mean to you?
And then told them that 'Map' is an interface - most implementations do NOT guarantee any order at all for either the keys or the values.
1. use 'entrySet' to get the 'Set' of the values - then use 'iterator' to to get one and iterate to the end or use 'toArray' and then access the last element of the array
2. use 'keySet' to get the 'Set' of the keys - then use 'iterator' iterate to get one and iterate to the end of the keys and then use that key to get the corresponding value. Or use 'toArray', access the last element of the array and use that key to get the corresponding map value.
3. use 'values' to get the 'Collection' of the values - then do the same as #1 above
But, generally speaking, a 'Map' does NOT have a first or last element.
-
You can use TreeMap and its method lastKey()
-
A TreeMap is a Map representation of a Tree, not an actual Map...
-
Sorting is provided by SortedMap<K,V> in which the lastKey() method returns the last (highest) key currently in the map.