Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a program to demonstrate the Repeated Parameters in Scala. Repeated Parameters are useful when passing variable length argument list i.e., the function is capable of accepting any number of Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Scala program to sort Employees objects based on their experience using Ordered trait.
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 |
package com.clearurdoubt class Employee(val name: String, val experience: Double, val salary: Double) extends Ordered[Employee] { override def compare(employee2: Employee) = this.experience compare employee2.experience override def toString = s"$name : $experience : $salary" } object Employee { def main(args: Array[String]) { val employees = List(new Employee("Ram", 2.09, 22000.00), new Employee("Raghu", 1.5, 20000.00), new Employee("Chaitanya", 3.2, 27000.00)) println("Employees: \n" + employees) println("Employees sorted based on experience: \n" + employees.sorted) } } |
Output: We have to implement compare function in Ordered trait to make a custom Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Scala program to sort a List of items. The “sorted()” function will sort the list of items based on their natural ordering. Let’s look at the program:
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 |
package com.clearurdoubt object ListSortDemo { def main(args: Array[String]) = { val numbers = List(12, 10, 9, 1, 15, 11, 8, 4) val strings = List("Gowtham", "Avinash", "Prajith", "Karthik") println("Numbers: \n" + numbers) println("Sorted Numbers: \n" + numbers.sorted) println("Strings: \n" + strings) println("Sorted Strings: \n" + strings.sorted) } } |
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Scala program to implement a Calculator operations. Let’s look at the program:
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 |
package com.clearurdoubt class Calculator { def +(a: Int, b: Int): Int = a+b def -(a: Int, b: Int): Int = a-b def *(a: Int, b: Int): Long = a*b def /(a: Int, b: Int): Int = { require(b != 0, "denominator can not be 0") a/b } } object Calendar { def main(args: Array[String]) = { val calc = new Calculator() println("Addition: " + calc.+(10, 2)) println("Subtraction: " + calc.-(10, 2)) println("Multiplication: " + calc.*(10, 2)) println("Division: " + calc./(10, 2)) //println("Division: " + calc./(10, 0)) } } |
Output: We have created a Calculator class with 4 typical calculator methods +(addition), -(subtraction), *(multiplication) Read more
“Hello World..!” – Probably the first message that any developer tries to print on the console, while learning a new programming language. Let’s write a basic Scala program to print “Hello World..!” message on the console and go through each Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at updating a column value based on another column value in a dataframe using when() utility function in Spark.
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 |
Spark context available as 'sc' (master = local[*], app id = local-1560028311690). Spark session available as 'spark'. Welcome to ____ __ / __/__ ___ _____/ /__ _\ \/ _ \/ _ `/ __/ '_/ /___/ .__/\_,_/_/ /_/\_\ version 2.4.3 /_/ Using Scala version 2.11.12 (Java HotSpot(TM) 64-Bit Server VM, Java 12.0.1) Type in expressions to have them evaluated. Type :help for more information. scala> val df = spark.read.json("/clearurdoubt/output.json"); df: org.apache.spark.sql.DataFrame = [first_name: string, id: bigint ... 2 more fields] scala> df.show(false); +----------+---+---------+------------+ |first_name|id |last_name|student_type| +----------+---+---------+------------+ |Rahul |101|Kumar |1 | |Antony |102|James |0 | |Ashok |103|Kedar |0 | |Ravi |104|Aswin |1 | +----------+---+---------+------------+ scala> val new_df = df.withColumn("student_type_description", when(col("student_type").equalTo("1"), lit("Day-Scholar")).otherwise("Residential")); new_df: org.apache.spark.sql.DataFrame = [first_name: string, id: bigint ... 3 more fields] scala> new_df.show(false); +----------+---+---------+------------+------------------------+ |first_name|id |last_name|student_type|student_type_description| +----------+---+---------+------------+------------------------+ |Rahul |101|Kumar |1 |Day-Scholar | |Antony |102|James |0 |Residential | |Ashok |103|Kedar |0 |Hostler | |Ravi |104|Aswin |1 |Residential | +----------+---+---------+------------+------------------------+ scala> |
WHEN() function documentation: static Column when(Column condition, Object value) Evaluates a list Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Java program to create a JSON file using JSON-simple API. JSON-simple API is used to create and read JSON files in a simple way. Maven dependency for Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at withColumn() function in Apache Spark SQL API. withColumn(String columnName, Column newColumn) is used to add a new column to a dataframe. Let’s look at the below code snippet in spark-shell for Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at withColumnRenamed() function in Apache Spark SQL API. withColumnRenamed(String columnName, String newColumnName) is used to rename a column in a Dataframe. Let’s look at the below code snippet in spark-shell for Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at the introduction of Functional Interfaces and Lambda Expressions in Java 8. One of the great updates in Java 8 is the addition of Lambda Expression support. Functional interfaces are Read more