Writing a CorDapp

When writing a CorDapp, you are writing a set of files in a JVM language that defines one or more of the following Corda components:

• States (i.e. classes implementing ContractState)
• Contracts (i.e. classes implementing Contract)
• Flows (i.e. classes extending FlowLogic)
• Web APIs
• Services

CorDapp structure

Your CorDapp project’s structure should be based on the structure of the Java Template CorDapp or the Kotlin Template CorDapp, depending on which language you intend to use.

The src directory of the Template CorDapp, where we define our CorDapp’s source-code, has the following structure:

src
├── main
│   ├── java
│   │   └── com
│   │       └── template
│   │           ├── Main.java
│   │           ├── api
│   │           │   └── TemplateApi.java
│   │           ├── client
│   │           │   └── TemplateClientRPC.java
│   │           ├── contract
│   │           │   └── TemplateContract.java
│   │           ├── flow
│   │           │   └── TemplateFlow.java
│   │           ├── plugin
│   │           │   └── TemplatePlugin.java
│   │           ├── service
│   │           │   └── TemplateService.java
│   │           └── state
│   │               └── TemplateState.java
│   └── resources
│       ├── META-INF
│       │   └── services
│       │       ├── net.corda.core.serialization.SerializationWhitelist
│       │       └── net.corda.webserver.services.WebServerPluginRegistry
│       ├── certificates
│       │   ├── sslkeystore.jks
│       │   └── truststore.jks
│       └──templateWeb
│           ├── index.html
│           └── js
│               └── template-js.js
└── test
    └── java
        └── com
            └── template
                └── contract
                    └── TemplateTests.java