Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at replacing a string with another string in a file in UNIX. We can use the sed command to replace the strings in a file. Syntax: sed -i ‘s/<current-string>/<replacement-string>/g’ <file-path> Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at the demo of List and ArrayList using forEach and Comparator in Java 8. forEach: brand new for loop for looping through the objects in a collection using lambda expressions Comparator: Java 8 Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Program to sort objects using Comparator Interface in Java 8. Consider a Student object having properties like rollno, name and marks. We will try to sort the objects based Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Java Program to sort objects using Comparable Interface. Consider a Student object having properties like rollno, name and marks. We will try to sort the objects based on Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at the WordCount program in Spark using Scala. Here is the Scala program:
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package com.sample import org.apache.spark._ object ScalaWordCounts { def main(args: Array[String]) { val conf = new SparkConf().setAppName("Scala Word Count").setMaster("local") val sc = new SparkContext(conf) val lines = sc.textFile(args(0)) val words = lines.flatMap(line => line.split(" ")) val pairs = words.map(word => (word, 1)) val counts = pairs.reduceByKey((count1, count2) => (count1 + count2)) counts.saveAsTextFile(args(1)) sc.stop() } } |
Input(HDFS) file:
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[admin@myworkstation ~]$ hadoop fs -cat /user/workspace/clearurdoubt/test_folder1/testfile_1.txt This is a test file. it is created for the practice purpose. [admin@myworkstation ~]$ |
Spark-submit command:
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spark-submit --master local --class com.sample.ScalaWordCounts /user/workspace/clearurdoubt/lib/ScalaWordCount-0.0.1-SNAPSHOT.jar /user/workspace/clearurdoubt/test_folder1/testfile_1.txt /user/workspace/clearurdoubt/word_count_output/ |
Output:
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[admin@myworkstation ~]$ hdfs dfs -cat /user/workspace/clearurdoubt/word_count_output/* (created,1) (it,1) (is,2) (practice,1) (a,1) (,1) (This,1) (for,1) (file.,1) (purpose.,1) (the,1) (test,1) [admin@myworkstation ~]$ |
Happy Learning! 🙂 Please Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Java program to print the Fibonacci series. Fibonacci Series: A series of numbers in which each number (Fibonacci number) is the sum of the two preceding numbers. Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Java program to print the counts of chars and digits in the given text. This can be achieved using “Character” class defined “java.lang” package. Here is the Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Java Program to count the number of vowels in a given text. This can be achieved using “String.toCharArray()” and “switch” statements. Here is the Java Program:
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package com.sample.clearurdoubt; import java.util.Scanner; public class VowelsCounter { public static void main(String[] args) { System.out.println("Enter some text:"); Scanner input = new Scanner(System.in); System.out.println("Tne number of vowels in the given text are : " + vowelsCounter(input.nextLine())); input.close(); } private static int vowelsCounter(String userInput) { int counter = 0; for(char c : userInput.toCharArray()) { switch(c) { case 'a': case 'e': case 'i': case 'o': case 'u': case 'A': case 'E': case 'I': case 'O': case 'U': counter++; default: continue; } } return counter; } } |
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Java program to find whether a number is even or odd without using modulus/division operator. Without using the Modulus/division operator, this can be achieved by using “bitwise Read more
Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at how a negative number is represented in binary format in Java. All the integer types in Java are signed integers i.e., they represent both positive and negative numbers. Java Read more