Updated on 2023-03-07 GMT+08:00

Gateway Java Demo

This section provides a demo based on Fabric Gateway for Java. Fabric Gateway Java encapsulates the Java SDK, which reduces the code amount and helps users develop Java client applications.

Common APIs

When you use Fabric-Gateway-Java to initiate transactions and query data, the Network and Contract interfaces are used. For more interfaces, see the Fabric official website.

  • Network

    The common interfaces are as follows:

    API

    Description

    Setting

    Returned Values

    getContract

    Gets an instance of a contract.

    String chaincodeId

    Contract

    addBlockListener

    Adds a listener to listen to block events.

    Consumer<org.hyperledger.fabric.sdk.BlockEvent> listener

    Consumer<org.hyperledger.fabric.sdk.BlockEvent>

    getChannel

    Gets the channel associated with the network.

    /

    org.hyperledger.fabric.sdk.Channel

    removeBlockListener

    Removes a listener.

    Consumer<org.hyperledger.fabric.sdk.BlockEvent> listener

    void

  • Contract

    The common interfaces are as follows:

    API

    Description

    Setting

    Returned Values

    submitTransaction

    Submits a transaction. The invocation method and parameters need to be entered.

    String name, String... args

    byte[]

    evaluateTransaction

    Evaluates a transaction. The invocation method and parameters need to be entered.

    String name, String... args

    byte[]

    createTransaction​

    Creates a transaction. The transaction needs to be submitted.

    String name

    Transaction

    addContractListener

    Adds a listener to listen to events emitted by committed transactions.

    Consumer<ContractEvent> listener

    Consumer<ContractEvent> listener

    removeContractListener​

    Removes a listener.

    Consumer<ContractEvent> listener

    void