update readme

Author: SidneyAllen

README.md

@@ -1,2 +1,60 @@
-# xero-java-oauth2-starter
-Java starter code for use with Xero-Java SDK to complete OAuth 2 flow
+
+# Xero Java oAuth2 Starter
+This Java project contains the code necessary to use the Xero-Java SDK and complete OAuth 2 flow
+
+Note: this project was built & tested using [Visual  Studio Code](https://code.visualstudio.com/) and [Apache Tomcat 9.x](http://tomcat.apache.org/) server.
+
+## Create a Xero App
+To obtain your API keys, follow these steps and create a Xero app
+
+* Create a [free Xero user account](https://www.xero.com/us/signup/api/) (if you don't have one)
+* Login to [Xero developer center](https://developer.xero.com/myapps)
+* Click "New App" link
+* Enter your App name, company url, privacy policy url.
+* Enter the redirect URI (this is your callback url - i.e. localhost:8080/starter/Callback)
+* Agree to terms and condition and click "Create App".
+* Click "Generate a secret" button.
+* Copy your client id and client secret and save for use later.
+* Click the "Save" button. You secret is now hidden.
+
+## Add your API keys to this app
+You'll need to set the *clientId, clientSecret and redirectURI* in the following files
+
+* Authorization.java
+* Callback.java
+* TokenRefresh.java
+
+## Build and deploy
+Compile your app and deploy to a server (tomcat, etc)
+```sh
+mvn clean install
+```
+
+Deploy on Tomcat or other Java server.
+
+## License
+
+This software is published under the [MIT License](http://en.wikipedia.org/wiki/MIT_License).
+
+	Copyright (c) 2019 Xero Limited
+
+	Permission is hereby granted, free of charge, to any person
+	obtaining a copy of this software and associated documentation
+	files (the "Software"), to deal in the Software without
+	restriction, including without limitation the rights to use,
+	copy, modify, merge, publish, distribute, sublicense, and/or sell
+	copies of the Software, and to permit persons to whom the
+	Software is furnished to do so, subject to the following
+	conditions:
+
+	The above copyright notice and this permission notice shall be
+	included in all copies or substantial portions of the Software.
+
+	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+	EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+	OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+	NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+	HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+	WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+	FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+	OTHER DEALINGS IN THE SOFTWARE.