Motivation

● Learn about data stream management systems and complex event processing.

● Learn to use Esper.

● Esper is a component for complex event processing (CEP),

available for Java.

● http://esper.codehaus.org/

● Allow passing students to take the final exam.

Changes from last year

No longer allowed to work in groups

New exercises

New deadline (Wednesday ,Sept. 30, 2015, 12:00 h)

Objective

● Use Esper to learn about CEP and to do queries on a stream of

stock events called ticks.

● Answer text questions to show that you have understood the

difference with traditional database systems.

You will have to learn about Esper and its query language EPL,

but you are not tested on your knowledge of stocks and

finance.

Getting Started

● Read about Esper at http://esper.codehaus.org/

● Download and extract

www.uio.no/studier/emner/matnat/ifi/INF5100/h15/exerc

ise/mandatory_exercise.tar.gz

● This bundle contains two directories:

● esper-4.9.0/

● inf5100/

esper-4.9.0/

● This is the Esper system and libraries, downloaded from

http://esper.codehaus.org/esper/download/download.html

● 4.9.0 is the newest version as of now, but you are free to

update if newer versions appear.

● You do not have to alter anything in this directory.

● However, the folder should be explored in order to

understand how Esper works.

● The folder also contains example programs that you can have

a look at, and learn from!

inf5100/

● This folder contains the “pre code” and files that you should

utilize in this exercise.

How to start working with Esper

● You need Eclipse JEE and JRE

● File → New Project (Give location of inf5100 pre code folder)

● Add external jars

inf5100/Makefile

● http://en.wikipedia.org/wiki/Make_(software)

● http://www.gnu.org/software/make/manual/make.html

● make - compiles the exercise

● make run - runs the queries

● make clean - removes the compiled Java classes

● You are free to expand the file if needed

inf5100/INF5100.java

● The code used to generate events (Esper ticks) and read your

queries.

● You do not need to modify this file, but you are allowed to

improve it if needed.

inf5100/Tick.java

– We only look at one single stock, BTC. ● timestamp = The date of the event/tick.

– Our stock exchange sends one tick per day. ● open = The price of the stock at the beginning of the day.

● high = The highest price the stock was traded for this day.

● low = The lowest price the stock was traded for this day.

● close = The price of the stock at the end of the day.

● volume = The number of times the stock was sold this day.

● weightedPrice = A weighted average of the stock price this day.

inf5100/Tick.java

SYMBOL = BTC = NAME OF THE STOCK

inf5100/BTC.csv

● The emulated stock exchange, consisting of events (ticks). You are not

allowed to modify this file, but you may look at it in order to verify the

correctness of your queries. It looks like: ● [...]

● 2010-07-18,0.04951,0.08585,0.05941,0.08584,75.01,0.07 ● 2010-07-19,0.08584,0.09307,0.07723,0.0808,574,0.09 ● 2010-07-

20,0.0808,0.08181,0.07426,0.07474,262,0.08 ● [...]

● As, you see, it is only a comma separated list of the 8 attributes from

Tick.java: timestamp, open, high, low, close, volume, average

inf5100/query_[...].epl

● These are the files you should change according to the

questions.

● E.g. “Find the date and weighted price of the BTC stock when

volume is greater than 200000.” → query_1.epl

Questions

● Both text and EPL questions.

● The ordering matters! Question 1 is easier than question

13. Solve the questions in order...

● Every question must be answered to pass!

Text Questions

● Questions 1, 3, 8, 10, 13, 15, 17

● Teaches you theory about CEP and EPL you might need in the

coming queries.

● Must be at least the page requirement listed in parenthesis.

E.g. (~1 page)

● You are not meant to copy/paste from either the Esper web-

page or the slides, but rather read, understand and write the

things in your own words.

EPL Questions

● Questions 2, 4, 5, 6, 7, 9, 11, 12, 14, 16

● Gives you practice in thinking in CEP environments and

teaches you EPL.

● Must include:

● How you think

● The EPL query

● Results (Output from Esper, nicely formatted)

● Graph of the the results

Delivery

● When: (Wednesday ,Sept. 30, 2015, 12:00 h) (Firm

deadline!)

● What: 1 PDF with all queries, explanations of how you

resonate, table with results and graphs where suited. Your

queries should be explained thoroughly, since there are many

possible solutions.

Q & A

● Please contact me at vivekk@ifi.uio.no if anything is unclear! I

will do my best to help via email!