workattech · setiaparul · Jun 8, 2020 · Jun 8, 2020 · Jun 8, 2020 · Jun 8, 2020
diff --git a/README.md b/README.md
@@ -1,3 +1,43 @@
+# **High Level Design for SplitWise**
+## Functional Requirements
+~ Users Can be sign up/ sign in to your system<br />
+~ Users can add thier contacts in the system by email or phone<br />
+~ Users can add Expense in the System with multiple contacts<br />
+~ Users can create groups and can add group expense with the group members<br />
+~ System has to show balance report of all users<br />
+~ System can show balance report of particular User<br />
+~ System can show balance report of all and particular group <br />
+
+## Non Functional Requirements<br />
+~The system should be highly available.Because if the service is down , no user will be able to access it.<br />
+
+## Extended Requirements<br />
+~System can simplyfy debts<br />
+~System can show passbook to user.The entries should show all the transactions a user was part of<br />
+
+## Capacity Estimation
+Read will be more than writes in this system.Lets assume if each user has 20 contacts . So read vs write ratio will be 20:1.<br />
+## Traffic estimates<br />
+Lets assume we have 20M new users per month with 20:1 read and write then we can expect 20*20M =>400M read<br />
+#### Queries per Second (QPS) will be 20M / (30 days * 24 hours * 3600 sec) ~= 7.71 write/sec<br />
+#### Consedering 20:1 read to write request 20 * 7.71 ~= 154.2 read/sec<br />
+
+## Storage Estimates<br />
+Lets assume we are saving the expense over the year of 5 years then 20M write request every month, total number of obects we<br /> 
+expect to store will be : 20M * 5years * 30 months ~= 3Billion<br />
+if each object stored take 500 Byte . Total storage we need is ~= 3B * 500 ~= 1.5TB<br />
+
+## BandWidth estimates <br />
+For Write Request<br />
+Since there are 7.7 write request every sec , so total incoming data for our service will be : 7.7 * 500Bytes =~ 3.75 Kb/sec<br />
+For Read Request<br />
+Since there are 154.2 read request every sec , so total outgoing data for our service will be : 154.2 * 500Bytes =~ 75.29 Kb/sec <br />
+
+## Basic System Design <br />
+
+![SplitWise_HLD](https://user-images.githubusercontent.com/8611287/84053046-00810000-a9cf-11ea-8a05-3c6676b1373b.png)
+
+
 # mock-machine-coding-2
 Welcome to the 2nd Mock Machine Coding Round by [workat.tech](http://workat.tech).
 

diff --git a/SplitWise_low_level_uml.png b/SplitWise_low_level_uml.png
diff --git a/Splitwise.uml b/Splitwise.uml
@@ -0,0 +1,234 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Diagram>
+  <ID>JAVA</ID>
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+  <SelectedNodes />
+  <Categories>
+    <Category>Fields</Category>
+    <Category>Methods</Category>
+    <Category>Properties</Category>
+  </Categories>
+  <SCOPE>All</SCOPE>
+  <VISIBILITY>private</VISIBILITY>
+</Diagram>
+
diff --git a/input.txt b/input.txt
@@ -0,0 +1,8 @@
+EXPENSE u1 1000 4 u1 u2 u3 u4 EQUAL
+SHOW u4
+SHOW u1
+EXPENSE u1 1250 2 u2 u3 EXACT 370 880
+SHOW
+EXPENSE u4 1200 4 u1 u2 u3 u4 PERCENT 40 20 20 20
+SHOW u1
+SHOW
diff --git a/src/main/java/com/splitwise/driver/SplitwiseDriver.java b/src/main/java/com/splitwise/driver/SplitwiseDriver.java
@@ -0,0 +1,34 @@
+package com.splitwise.driver;
+
+
+import com.splitwise.io.InputTxtReader;
+import com.splitwise.model.User;
+import com.splitwise.model.UserRegistry;
+
+public class SplitwiseDriver{
+    private static UserRegistry userRegistry;
+
+    public static UserRegistry getUserRegistry(){
+        return userRegistry;
+    }
+    public static void main(String[] args) {
+            User u1 = new User("u1","88888888881","u1@abc.com");
+            User u2 = new User("u2","88888888882","u3@abc.com");
+            User u3 = new User("u3","88888888883","u2@abc.com");
+            User u4 = new User("u4","88888888884","u4@abc.com");
+            User u5 = new User("u5","88888888885","u5@abc.com");
+
+
+            userRegistry = new UserRegistry();
+            userRegistry.getUserRegistry().add(u1);
+            userRegistry.getUserRegistry().add(u2);
+            userRegistry.getUserRegistry().add(u3);
+            userRegistry.getUserRegistry().add(u4);
+            userRegistry.getUserRegistry().add(u5);
+
+            InputTxtReader reader = new InputTxtReader();
+            reader.readInputTxtFile("input.txt");
+
+
+        }
+    }
diff --git a/src/main/java/com/splitwise/io/InputTxtReader.java b/src/main/java/com/splitwise/io/InputTxtReader.java
@@ -0,0 +1,32 @@
+package com.splitwise.io;
+
+
+import com.splitwise.process.TransactionProcesser;
+
+import java.io.*;
+
+public class InputTxtReader {
+    TransactionProcesser processor;
+    public InputTxtReader(){
+        processor = new TransactionProcesser();
+    }
+    public void readInputTxtFile(String fileName) {
+        if(fileName==null && fileName.isEmpty()){
+            System.err.println("FileName is empty or Null . Aborting!!!");
+            return;
+        }
+       try {
+           File file = new File(fileName);
+           BufferedReader br = new BufferedReader(new FileReader(file));
+           String st;
+           while ((st = br.readLine()) != null) {
+               //System.out.println(st);
+                processor.process(st);
+           }
+       }catch(Exception e){
+           System.err.println("Exception while reading a file"+e);
+       }
+    }
+
+}
+
diff --git a/src/main/java/com/splitwise/model/Expense.java b/src/main/java/com/splitwise/model/Expense.java
@@ -0,0 +1,12 @@
+package com.splitwise.model;
+
+import java.util.List;
+
+public class Expense {
+
+    private User paidByUser;
+    private int amount;
+    private int noOfPeopleInExpense;
+    List<String> usersInExpense;
+
+}