# Supported Types

The IC4J **Candid Library** allows Java developers to serialize and deserialize Java native types to **IC Candid IDL types.**

*"Candid is an interface description language. Its primary purpose is to describe the public interface of a **service**, usually in the form of a program deployed as a **canister smart contract** that runs on the Internet Computer. One of the key benefits of Candid is that it is language-agnostic, and allows inter-operation between services and front-ends written in different programming languages, including Motoko, Rust, and JavaScript."*

{% embed url="<https://smartcontracts.org/docs/candid-guide/candid-concepts.html>" %}
What is Candid?
{% endembed %}

{% embed url="<https://smartcontracts.org/docs/candid-guide/candid-types.html>" %}
Candid Types
{% endembed %}

This table shows implicit mapping between Candid types and default Java type assignment.

| Candid    | Java        |
| --------- | ----------- |
| bool      | Boolean     |
| int       | BigInteger  |
| int8      | Byte        |
| int16     | Short       |
| int32     | Integer     |
| int64     | Long        |
| nat       | BigInteger  |
| nat8      | Byte        |
| nat16     | Short       |
| nat32     | Integer     |
| nat64     | Long        |
| float32   | Float       |
| float64   | Double      |
| text      | String      |
| opt       | Optional    |
| principal | Principal   |
| vec       | array, List |
| record    | Map, Class  |
| variant   | Map, Enum   |
| func      | Func        |
| service   | Service     |
| null      | Null        |


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