Obtaining the CorDapp Template

When writing a new CorDapp, you’ll generally want to start from one of the following standard templates:

The CorDapp templates provide the boilerplate for developing a new CorDapp. CorDapps can be written in either Java or Kotlin. Sample code is provided in both languages throughout this tutorial.

Note that there’s no need to download and install Corda itself. The required libraries are automatically downloaded from an online Maven repository and cached locally.

Downloading the template

Open a terminal window in the directory where you want to download the CorDapp template, and run the following command:

git clone https://github.com/corda/cordapp-template-kotlin.git ; cd cordapp-template-kotlin
git clone https://github.com/corda/cordapp-template-java.git ; cd cordapp-template-java

Opening the template in IntelliJ

Once the template is download, open it in IntelliJ by following the instructions here: Running a sample CorDapp.

Template structure

For this tutorial, you will only be modifying the following files:

// 1. The state
contracts/src/main/kotlin/com/template/states/TemplateState.kt

// 2. The flow
workflows/src/main/kotlin/com/template/flows/Flows.kt
// 1. The state
contracts/src/main/java/com/template/states/TemplateState.java

// 2. The flow
workflows/src/main/java/com/template/flows/Initiator.java

Progress so far

You now have a template that you can build upon to define your IOU CorDapp. Let’s start by defining the IOUState.