corda/docs/source/hello-world-template.rst

The CorDapp Template

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

• The Java Cordapp Template
• The Kotlin Cordapp Template

The Cordapp templates provide the boilerplate for developing a new CorDapp. CorDapps can be written in either Java or Kotlin. We will be providing the code 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-java.git ; cd cordapp-template-java

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

Opening the template in IntelliJ

Once the template is download, open it in IntelliJ by following the instructions here: https://docs.corda.net/tutorial-cordapp.html#opening-the-example-cordapp-in-intellij.

Template structure

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

// 1. The state
cordapp-contracts-states/src/main/java/com/template/TemplateState.java

// 2. The flow
cordapp/src/main/java/com/template/Initiator.java

// 1. The state
cordapp-contracts-states/src/main/kotlin/com/template/StatesAndContracts.kt

// 2. The flow
cordapp/src/main/kotlin/com/template/Flows.kt

Progress so far

We now have a template that we can build upon to define our IOU CorDapp. Let's start by defining the IOUState.