Java.util.TreeMap.firstEntry() and firstKey() in Java
There are two variants of first() in Java.util.TreeMap, both are discussed in this article.
1. firstEntry() : It returns a key-value mapping associated with the least key in this map, or null if the map is empty.
Syntax : public Map.Entry firstEntry() Parameters: NA Return Value: It returns an entry with the least key and null if the map is empty. Exception: NA
Lowest entry is: 1=one
2. firstKey() : It returns the first (lowest) key currently in the map.
Syntax : public K firstKey() Parameters: NA Return Value: It returns the first (lowest) key currently in this map. Exception: NA NoSuchElementException : It is thrown if this map is empty.
Lowest key is: 1
Practical Application : These functions can be used to fetch best ranked person in given list, or can be used to assign winner in game in which person with lowest time to finish a task wins. Latter one is discussed below.
Winner with lowest time is : 1.3=Shambhavi
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