> ## Documentation Index
> Fetch the complete documentation index at: https://docs.blnkfinance.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Quick Start
> Install the Java SDK and create your first transaction.
export const CtaCallout = props => {
const {title, buttonLabel, href, trackingEvent, buttonTarget, rel = "noopener noreferrer", children} = props;
const handleCtaClick = () => {
if (typeof window === "undefined" || !trackingEvent) {
return;
}
try {
window.dispatchEvent(new CustomEvent("blnk:docs-cta", {
detail: {
name: trackingEvent,
href
}
}));
} catch {}
try {
window.posthog?.capture?.(trackingEvent, {
href
});
} catch {}
const gaPayload = {
cta_href: href
};
try {
window.gtag?.("event", trackingEvent, gaPayload);
} catch {}
try {
window.dataLayer = window.dataLayer || [];
window.dataLayer.push({
event: trackingEvent,
...gaPayload
});
} catch {}
};
const isExternal = typeof href === "string" && (/^https?:\/\//i).test(href);
const target = buttonTarget ?? (isExternal ? "_blank" : undefined);
const linkRel = isExternal ? rel : undefined;
return ;
};
This guide walks you through adding the Blnk Java SDK to your project, initializing the client, and creating your first transaction.
By the end, you'll have a working connection to Blnk and be ready to build financial products from your Java application.
Add the dependency from [Maven Central](https://central.sonatype.com/artifact/com.blnkfinance/blnk-java). Requires JDK 17 or later.
```xml pom.xml wrap theme={"system"}
com.blnkfinance
blnk-java
1.3.0
```
Gradle:
```kotlin wrap theme={"system"}
implementation("com.blnkfinance:blnk-java:1.3.0")
```
Create a `Main.java` file as shown below to create your first transaction with the SDK.
Make sure you have a running Blnk Core instance. Set the URL and API key as environment variables in your project.
```java Main.java wrap theme={"system"}
import com.blnkfinance.blnk.Blnk;
import com.blnkfinance.blnk.BlnkClientOptions;
import com.blnkfinance.blnk.types.ApiResponse;
import com.blnkfinance.blnk.types.CreateTransactions;
import com.fasterxml.jackson.databind.JsonNode;
public class Main {
public static void main(String[] args) {
String apiKey = System.getenv().getOrDefault("BLNK_API_KEY", "");
String baseUrl = System.getenv().getOrDefault(
"BLNK_BASE_URL",
"http://localhost:5001"
);
Blnk blnk = Blnk.init(
apiKey,
BlnkClientOptions.builder()
.baseUrl(baseUrl)
.build());
ApiResponse response = blnk.transactions().create(
CreateTransactions.create()
.preciseAmount(100000)
.reference("first_txn_001")
.currency("USD")
.precision(100)
.source("@FundingPool")
.destination("@MyBalance")
.description("My first Blnk transaction")
.allowOverdraft(true)
);
if (response.status() != 201 || response.data() == null) {
throw new RuntimeException(response.message());
}
System.out.println(response.data().toPrettyString());
}
}
```
Compile and run.
```bash wrap theme={"system"}
mvn compile exec:java -Dexec.mainClass="Main"
```
You should get a response similar to:
```json 201 Created wrap expandable theme={"system"}
{
"amount": 1000,
"precision": 100,
"precise_amount": 100000,
"transaction_id": "txn_8d2ce2f0-0d75-4a91-9d43-2ad2c2e6b9ad",
"parent_transaction": "",
"source": "bln_f344b673-e855-4bda-b769-3e94a02c1941",
"destination": "bln_d5cbde84-d20a-485b-8ce8-6677d782c3a1",
"reference": "first_txn_001",
"currency": "USD",
"description": "My first Blnk transaction",
"status": "QUEUED",
"hash": "0b9c25fb5b00d6c71cb4ca87026bf6dc316e63353d3330deb588bd0b3d74dcc0",
"allow_overdraft": true,
"inflight": false,
"created_at": "2024-11-26T09:33:35.265582042Z",
"scheduled_for": "0001-01-01T00:00:00Z",
"inflight_expiry_date": "0001-01-01T00:00:00Z",
"inflight_commit_date": "0001-01-01T00:00:00Z"
}
```
Confirm the transaction landed in your ledger.
1. Open **Transactions** in the sidebar.
2. Find your transaction by reference (`first_txn_001`) or by the `transaction_id` from the script output.
3. Click the row to open the details and verify the amount, status, source, and destination.
If the transaction is missing, click **Refresh** on the table to pull the latest data from Core.
Fetch the transaction by ID:
```bash wrap theme={"system"}
blnk transactions list --id txn_8d2ce2f0-0d75-4a91-9d43-2ad2c2e6b9ad
```
Replace the transaction ID with the value printed by your class.
***
## Related docs
Authentication, timeouts, retries, and logging.
ApiResponse checks and Core error bodies.
Java SDK releases and version history.
***
## Need help?
We are very happy to help you make the most of Blnk, regardless of whether it is your first time or you are switching from another tool.
To ask questions or discuss issues, please [contact us](mailto:support@blnkfinance.com) or [join our Discord community](https://discord.gg/7WNv94zPpx).
Sign up and manage your ledger with our back-office dashboard. You can invite teammates to collaborate and manage your ledger operations directly from the dashboard.