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Working with Serverless and Java - Part 1

In this tutorial, we will create and deploy a java-maven based serverless service using the serverless project (https://serverless.com/). In this part we will not modify any code, or even look at the generated code. We will focus on the deployment and the command line interface provided by serverless. Serverless is a node.js based framework that makes creating, deploying, and managing serverless functions a breeze. We will use AWS as our FaaS (Function-as-a-Service) provider.

Pre-requisites

Here is what the setup on my Mac looks like (Sierra)

• brew (1.1.10) - you will need this if you do not have node/npm installed already.
• node (v7.6.0)
• npm (4.1.2)
• Apache Maven (3.2.5)

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import java.util.Stack;

public class DecimalToAnyBaseConverter {

    /*
        We use base 62 array for all base conversions
     */
    char[] base62 = new char[62];

    /*

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FROM ubuntu:latest
RUN apt-get -y update && apt-get -y upgrade
RUN apt-get -y install openjdk-8-jdk wget
RUN mkdir /usr/local/tomcat
RUN wget http://www-us.apache.org/dist/tomcat/tomcat-8/v8.5.16/bin/apache-tomcat-8.5.16.tar.gz -O /tmp/tomcat.tar.gz
RUN cd /tmp && tar xvfz tomcat.tar.gz
RUN cp -Rv /tmp/apache-tomcat-8.5.16/* /usr/local/tomcat/
EXPOSE 8080
CMD /usr/local/tomcat/bin/catalina.sh run

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Starting localstack

C02STG51GTFM:localstack mpandit$ make infra
. .venv/bin/activate; exec localstack/mock/infra.py
Starting local dev environment. CTRL-C to quit.
Starting local Elasticsearch (port 4571)...
Starting mock ES service (port 4578)...
Starting mock S3 server (port 4572)...
Starting mock SNS server (port 4575)...

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Specify packaging as individual in serverless.yml

service: aws-java-maven # NOTE: update this with your service name

provider:
  name: aws
  runtime: java8

package:

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def reverse_string(s):
    if len(s)==1:
        return s
    else:
        return s[-1]+reverse_string(s[0:len(s)-1])

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package org.lobster1234.misc;

import junit.framework.TestCase;

import java.util.concurrent.TimeUnit;

public class TokenBucketRateLimiterTest extends TestCase {

    public void testTokenBucketRateLimiter() {
        try {

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package org.lobster1234.misc;


import java.util.concurrent.*;
import java.util.function.Consumer;

/**
 * Implementation of a token bucket rate limiter.
 */
public class TokenBucketRateLimiter {

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public class LinkedList<T> {

	private LinkedListNode<T> first = null;
	
	/**
	 * Insert at the front of the list
	 * @param node
	 */
	public void insert(LinkedListNode<T> node) {
		node.setNext(first);

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public class WaitNotifyExample {

  public static void main(String[] args) {
		Integer lock = new Integer(0);
		Thread waiter = new Thread(new Waiter(lock));
		waiter.start();
		Thread notifier = new Thread(new Notifier(lock));
		notifier.start();
	}