https://github.com/casper-network/casper-java-sdk
Java library for interacting with a CSPR node
https://github.com/casper-network/casper-java-sdk
Last synced: 5 months ago
JSON representation
Java library for interacting with a CSPR node
- Host: GitHub
- URL: https://github.com/casper-network/casper-java-sdk
- Owner: casper-network
- License: apache-2.0
- Created: 2021-07-14T09:30:03.000Z (almost 5 years ago)
- Default Branch: main
- Last Pushed: 2025-11-14T14:21:33.000Z (7 months ago)
- Last Synced: 2025-11-14T16:18:32.576Z (7 months ago)
- Language: Java
- Size: 89.3 MB
- Stars: 10
- Watchers: 5
- Forks: 25
- Open Issues: 35
-
Metadata Files:
- Readme: README.md
- Contributing: CONTRIBUTING.md
- License: LICENSE
- Security: SECURITY.md
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README
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# Casper Java SDK
This project implements the SDK to interact with a Casper Node. It wraps the Json-RPC requests and maps the results to Java objects.
## Dependencies
- Java 8
- Gradle
- [crypto-keys](https://github.com/crypto-keys)
## Build instructions
```
./gradlew build
```
## Including the library
Using gradle:
```gradle
implementation 'network.casper:casper-java-sdk:2.4.1'
```
Using maven:
``` xml
network.casper
casper-java-sdk
2.4.1
```
## How to
### 1. [Set-up a connection](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/AbstractJsonRpcTests.java#L23-L39)
```Java
casperService = CasperService.usingPeer("127.0.0.1","7777");
```
### 2. Query a block
Retrieve block info by a block identifier
#### [Last block](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L119)
```Java
JsonBlockData result = casperService.getBlock();
```
#### [By height](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L138-L139)
```Java
JsonBlockData result = casperService.getBlock(new HeightBlockIdentifier(1234));
```
#### [By hash](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L126-L127)
```Java
JsonBlockData blockData = casperService.getBlock(new HashBlockIdentifier("--hash--"));
```
### 3. Query transfers
Retrieve block transfers by a block identifier
#### [Last block](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L148)
```Java
TransferData transferData = casperService.getBlockTransfers();
```
#### [By block height](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L155)
```Java
TransferData transferData = casperService.getBlockTransfers(new HeightBlockIdentifier(1234));
```
#### [By block hash](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L170-L171)
```Java
TransferData transferData = casperService.getBlockTransfers(new HashBlockIdentifier("--hash--"));
```
### 3. Query state root hash
Retrieve the state root hash given the BlockIdentifier
#### [Last block](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L186)
```Java
StateRootHashData stateRootData = casperService.getStateRootHash();
```
#### [By block height](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L193)
```Java
StateRootHashData stateRootData = casperService.getStateRootHash(new HeightBlockIdentifier(1234));
```
#### [By block hash](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L201-L202)
```Java
StateRootHashData stateRootData = casperService.getStateRootHash(new HashBlockIdentifier("--hash--"));
```
### 4. [Query deploy](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L225-L226)
Get a Deploy from the network
```Java
DeployData deployData = casperService.getDeploy("--hash--");
```
### 5. [Query peers](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L111)
Get network peers data
```Java
PeerData peerData = casperService.getPeerData();
```
### 6. [Query stored value](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L212-L215)
Retrieve a stored value from the network
```Java
StoredValueData result = casperService.getStateItem("--stateRootHash--", "key", Arrays.asList("The path components starting from the key as base"));
```
### 7. [Get node status](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L242)
Return the current status of the node
```Java
StatusData status = casperService.getStatus()
```
### 8. Get account info
Returns an Account from the network
#### [By block height](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L280-L282)
```Java
AccountData account = casperService.getStateAccountInfo("--publicKey--", new HeightBlockIdentifier(1234));
```
#### [By block hash](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L268-L270)
```Java
AccountData account = casperService.getStateAccountInfo("--publicKey--", new HashBlockIdentifier("--hash--"));
```
### 9. Get auction info
Returns the Auction info for a given block
#### [By block height](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L302)
```Java
AuctionData auction = casperService.getStateAuctionInfo(new HeightBlockIdentifier(1234));
```
#### [By block hash](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L292-L293)
```Java
AuctionData auction = casperServiceMainnet.getStateAuctionInfo(new HashBlockIdentifier("--hash--"));
```
### 10. Get era info
Returns an EraInfo from the network
#### [By block height](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L311)
```Java
EraInfoData eraInfoData = casperService.getEraInfoBySwitchBlock(new HeightBlockIdentifier(1234));
```
#### [By block hash](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperServiceTests.java#L325-L326)
```Java
EraInfoData eraInfoData = casperService.getEraInfoBySwitchBlock(new HashBlockIdentifier("--hash--"));
```
### 11. Deploy
#### [Transfering CSPR ](https://github.com/casper-network/casper-java-sdk/blob/main/src/test/java/com/casper/sdk/service/CasperDeployServiceTests.java#L73-L77)
```Java
Deploy deploy = CasperDeployService.buildTransferDeploy(from, to,
BigInteger.valueOf(2500000000L), "casper-test",
id, BigInteger.valueOf(100000000L), 1L, ttl, new Date(),
new ArrayList<>());
DeployResult deployResult = casperServiceTestnet.putDeploy(deploy);
```
### 12. Consuming Events
The Java SDK supports the consumption of casper events using the event service API. This API allows the consumer to
choose the events to be provided as Pojos or as raw JSON via the EventTarget enum values. Each event stream is consumed
individually by providing the required stream (main, sigs, and deploys) using the EventType parameter to the consumeEvents method.
For more information on events see: [Monitoring and Consuming Events](https://docs.casperlabs.io/dapp-dev-guide/building-dapps/monitoring-events/).
#### Consuming Raw JSON Event Strings
```Java
// Construct an events service
final EventService eventService = EventService.usingPeer(new URI("http://localhost:28101"));
// Consume the main events as raw JSON
eventService.consumeEvents(EventType.MAIN, EventTarget.RAW, 0L, new EventConsumer(){
@Override
public void accept(final Event event) {
// Obtain the raw JSON event as a String
final String json = event.getData();
// Obtain the optional event ID
final long id = event.getId().orElse(0L);
}
});
```
#### Consuming Pojo Events
```Java
// Construct an events service
final EventService eventService = EventService.usingPeer(new URI("http://localhost:28101"));
// Consume the main events as Casper Java SDK Pojos
eventService.consumeEvents(EventType.MAIN, EventTarget.POJO, 0L, new EventConsumer() {
@Override
public void accept(final Event event) {
switch (event.getDataType()) {
case BLOCK_ADDED:
handleBlockAdded(event.getId().get(), ((BlockAdded) event.getData()));
break;
// And so on...
}
}
});
```