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class OpeningTime {
    internal var isClosed = false
    internal val customerPresence: StringBuilder = StringBuilder()
}

fun computePenalty(log: String, closingTime: Int): Int {
    val logArray = log.split(" ")
    var penalty = 0
    for (i in logArray.indices) {
        if (i < closingTime) {

pkafel

package com.piotrkafel.ratelimiter;

import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.TimeUnit;

public class DifferentFixedWindowRateLimiter<T> {
    private final int windowMaxSize;
    private final Map<T, Window> store = new ConcurrentHashMap<>();
    private final long windowSizeInMillies;

pkafel

Welcome to Kafka from scratch workshops!

The below insructions will work on the assumption that

• You are using OSX
• You use Kafka 2.0 version

Exercise 1 (Setup)

1. Install Kafka on your machine - brew install kafka
2. Start Kafka together with ZooKeeper - zookeeper-server-start /usr/local/etc/kafka/zookeeper.properties & kafka-server-start /usr/local/etc/kafka/server.properties
3. Make sure auto.create.topics.enable property is set to true

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Kafka command line tools

List (not complete)

• zookeeper-server-start.sh - starting Zookeeper
• kafka-server-start.sh - start Kafka
• kafka-topics.sh - manage topics in Kafka
• kafka-console-producer.sh - script for sending messages to Kafka topic
• kafka-console-consumer.sh - script for consuming messages from Kafka topic
• kafka-run-class.sh - script for running different tools (list of tools can be found here)

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Most essential Intellij IDEA shortcuts (that I use in my everyday job)

All below shortcuts work on keymap Mac OS X (10.5+)

Search

• command + o - search class
• command + shift + o - search file
• command + alt + o - search symbol
• double shift - search everywhere
• alt + F7 - search for usage

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Java 9 features

Convenience Factory Methods for Collections (JEP 269)

Provide static factory methods on the List, Set and Map interfaces for creating unmodifiable instances of those collections.

List.of();
List.of(E e1);
List.of(E e1, E e2);