mateuszmrozewski

journalctl -k | grep -i -e memory -e oom

mateuszmrozewski

List.of(1, 2, 3, 3, 3, 4).stream()
  .distinct()
  .forEach(System.out::println);

mateuszmrozewski

Stream.generate(() -> Math.random())
        .mapToLong(x -> (long) (x * 10))
        .filter(x -> x % 2 == 0)
        .limit(10)
        .forEach(System.out::println);

mateuszmrozewski

PutObjectRequest putRequestUnencrytped = PutObjectRequest.builder()
        .bucket("myunencrypted-bucket")
        .key("my-file.png")
        .serverSideEncryption(ServerSideEncryption.AES256)
        .build();
client.putObject(putRequestUnencrytped, Paths.get("my-file.png"));

mateuszmrozewski

// Generate a random 256 bit AES key and encode it in Base64
KeyGenerator keyGenerator = KeyGenerator.getInstance("AES");
keyGenerator.init(256, new SecureRandom());
SecretKey secretKey = keyGenerator.generateKey();
String secretKeyString = Base64.getEncoder().encodeToString(secretKey.getEncoded());

// Generate md5 digest of the key and encode it in Base64
MessageDigest md5 = MessageDigest.getInstance("MD5");
md5.update(secretKey.getEncoded());
byte[] digest = md5.digest();

mateuszmrozewski

sudo wget http://repos.fedorapeople.org/repos/dchen/apache-maven/epel-apache-maven.repo -O /etc/yum.repos.d/epel-apache-maven.repo
sudo sed -i s/\$releasever/6/g /etc/yum.repos.d/epel-apache-maven.repo
sudo yum install -y apache-maven
mvn --version

mateuszmrozewski

sysctl -w kern.maxfiles=20480

sysctl -w kern.maxfilesperproc=18000

mateuszmrozewski

    @Bean
    public List<Declarable> queueDeclarations()
    {
        boolean durable = true;
        boolean autoDelete = false;
        boolean exclusive = false;
        Map<String, Object> args = new HashMap<>();
        args.put("x-dead-letter-exchange", "dl.exchange");
        args.put("x-dead-letter-queue", "dl.queue");
        return Arrays.asList(

mateuszmrozewski

#!/bin/bash
# Delete all containers
docker rm -f $(docker ps -a -q)
# Delete all images
docker rmi -f $(docker images -q)
# Delete dangling volumes
docker volume ls -qf dangling=true | xargs -r docker volume rm

mateuszmrozewski

object S99_P19 {
  def rotate[T](n: Int, ts: Seq[T]): Seq[T] = (n, ts) match {
    case (_, Nil) => Nil
    case (0, seq) => seq
    case (x, seq) => rotate(x - 1, seq.last +: seq take seq.length - 1)
  }
}