The filterKeys() method is utilized to find all the pairs where the keys satisfies the given predicate.
Method Definition: def filterKeys(p: (A) => Boolean): SortedMap[A, B]
Return Type: It returns all the “key-value” pairs of the SortedMap where, the keys satisfies the given predicate.
Example #1:
// Scala program of filterKeys() // method import scala.collection.immutable.SortedMap
// Creating object object GfG
{ // Main method
def main(args : Array[String])
{
// Creating SortedMap
val m 1 = SortedMap( 5 - > "geeks" , 4 - > "for" , 2 - > "cs" )
// Applying filterKeys method
val result = m 1 .filterKeys( _ > 2 )
// Displays output
println(result)
}
} |
Output:
Map(4 -> for, 5 -> geeks)
Here, only two key-value pairs are returned as their keys are greater than two as per the stated predicate.
Example #2:
// Scala program of filterKeys() // method import scala.collection.immutable.SortedMap
// Creating object object GfG
{ // Main method
def main(args : Array[String])
{
// Creating SortedMap
val m 1 = SortedMap( 3 - > "geeks" , 1 - > "for" , 2 - > "cs" )
// Applying filterKeys method
val result = m 1 .filterKeys( _ > 3 )
// Displays output
println(result)
}
} |
Output:
Map()
Here, no pair is returned as none of the keys satisfies the stated predicate.