TreeMap
Remove mapping from TreeMap example
This is an example of how to remove mapping from a TreeMap, that is removing a key value pair from a TreeMap. Removing mapping from a TreeMap implies that you should:
- Create a new TreeMap.
- Populate the map with elements, with
put(K key, V value)
API method of TreeMap. - Invoke
remove(Object o)
API method of TreeMap with a key as parameter. It removes the key value pair from the map. It returns either the value mapped with the key previously or null if no value was mapped.
Let’s take a look at the code snippet that follows:
package com.javacodegeeks.snippets.core; import java.util.TreeMap; public class RemoveMappingTreeMap { public static void main(String[] args) { // Create a TreeMap and populate it with elements TreeMap treeMap = new TreeMap(); treeMap.put("key_1","element_1"); treeMap.put("key_2","element_2"); treeMap.put("key_3","element_3"); System.out.println("TreeMap contains : " + treeMap); /* Object remove(Object key) operantion removes a key value pair from TreeMap. It returns either the value mapped with the key previously or null if no value was mapped. */ Object value = treeMap.remove("key_2"); System.out.println("After removing value : " + value + " TreeMap contains : " + treeMap); } }
Output:
TreeMap contains : {key_1=element_1, key_2=element_2, key_3=element_3}
After removing value : element_2 TreeMap contains : {key_1=element_1, key_3=element_3}
This was an example of how to remove mapping from a TreeMap in Java.