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xrpl-dev-portal/content/tutorials/use-simple-xrp-payments/send-xrp.md
nkramer44 762cd6dc34 remove SendPayment.java.
Add Java to send-xrp tutorial
2021-05-04 15:50:32 -04:00

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---
html: send-xrp.html
funnel: Build
doc_type: Tutorials
category: Get Started
blurb: Learn how to send test payments right from your browser.
cta_text: Send XRP
embed_ripple_lib: true
filters:
- interactive_steps
- include_code
---
# Send XRP
This tutorial explains how to send a simple XRP Payment using ripple-lib for JavaScript, xrpl-py for Python, or xrpl4j for Java. First, we step through the process with the [XRP Ledger Testnet](parallel-networks.html). Then, we compare that to the additional requirements for doing the equivalent in production.
**Tip:** Check out the [Code Samples](https://github.com/ripple/xrpl-dev-portal/tree/master/content/_code-samples) for a complete version of the code used in this tutorial.
## Prerequisites
<!-- Source for this specific tutorial's interactive bits: -->
<script type="application/javascript" src="assets/js/tutorials/send-xrp.js"></script>
{% set use_network = "Testnet" %}
To interact with the XRP Ledger, you need to set up a dev environment with the necessary tools. This tutorial provides examples using the following options:
- **JavaScript** with the [ripple-lib (RippleAPI) library](https://github.com/ripple/ripple-lib/). See the [RippleAPI Beginners Guide](get-started-with-rippleapi-for-javascript.html) for detailed instructions on getting started.
- **Python** with the [xrpl-py library](https://xrpl-py.readthedocs.io/). See [Get Started using Python](get-started-using-python.html) for setup steps.
- **Java** with the [xrpl4j library](https://github.com/XRPLF/xrpl4j). See [Get Started Using Java](get-started-using-java.html) for setup steps.
## Send a Payment on the Test Net
{% set n = cycler(* range(1,99)) %}
### {{n.next()}}. Get Credentials
To transact on the XRP Ledger, you need an address and secret key, and some XRP. The address and secret key look like this:
<!-- MULTICODE_BLOCK_START -->
_JavaScript_
{{ include_code("_code-samples/send-xrp/send-xrp.js", end_before="// Connect", language="js") }}
_Python_
{{ include_code("_code-samples/send-xrp/send-xrp.py", end_before="# Connect", language="py") }}
_Java_
{{ include_code("_code-samples/send-xrp/SendXrp.java", end_before="// Connect", language="java") }}
<!-- MULTICODE_BLOCK_END -->
The secret key shown here is for example only. For development purposes, you can get your own credentials, pre-funded with XRP, on the Testnet using the following interface:
{% include '_snippets/interactive-tutorials/generate-step.md' %}
When you're [building actual production-ready software](production-readiness.html), you'll instead use an existing account, and manage your keys using a [secure signing configuration](set-up-secure-signing.html).
### {{n.next()}}. Connect to a Testnet Server
First, you must connect to an XRP Ledger server so you can get the current status of your account and the shared ledger. You can use this information to automatically fill in certain required fields of a transaction. (For more security, you can sign transactions from a machine that doesn't have an internet connection, but only if you can provide all of the necessary details.) You also must be connected to the network to submit transactions to it.
The following code connects to one of the public Testnet servers that Ripple runs:
<!-- MULTICODE_BLOCK_START -->
_JavaScript_
{{ include_code("_code-samples/send-xrp/send-xrp.js", start_with="// Connect", end_before="// Get credentials", language="js") }}
_Python_
{{ include_code("_code-samples/send-xrp/send-xrp.py", start_with="# Connect", end_before="# Get credentials", language="py") }}
_Java_
{{ include_code("_code-samples/send-xrp/SendXrp.java", start_with="// Connect", end_before="// Prepare transaction", language="java") }}
<!-- MULTICODE_BLOCK_END -->
For this tutorial, you can connect directly from your browser by pressing the following button:
{% include '_snippets/interactive-tutorials/connect-step.md' %}
### {{n.next()}}. Prepare Transaction
Typically, we create XRP Ledger transactions as objects in the JSON [transaction format](transaction-formats.html). The following example shows a minimal Payment specification:
```json
{
"TransactionType": "Payment",
"Account": "rPT1Sjq2YGrBMTttX4GZHjKu9dyfzbpAYe",
"Amount": "2000000",
"Destination": "rUCzEr6jrEyMpjhs4wSdQdz4g8Y382NxfM"
}
```
The bare minimum set of instructions you must provide for an XRP Payment is:
- An indicator that this is a payment. (`"TransactionType": "Payment"`)
- The sending address. (`"Account"`)
- The address that should receive the XRP (`"Destination"`). This can't be the same as the sending address.
- The amount of XRP to send (`"Amount"`). Typically, this is specified as an integer in "drops" of XRP, where 1,000,000 drops equals 1 XRP.
Technically, a viable transaction must contain some additional fields, and certain optional fields such as `LastLedgerSequence` are strongly recommended. Some other language-specific notes:
- If you're using ripple-lib for JavaScript, you can use the [`prepareTransaction()` method](rippleapi-reference.html#preparetransaction) to automatically fill in good defaults for the remaining fields of a transaction.
- With xrpl-py for Python, you can use the models in `xrpl.models.transactions` to construct transactions as native Python objects.
- With xrpl4j for Java, you can use the model objects in the `xrpl4j-model` module to construct transactions as Java objects.
- Unlike the other SDKs, you must provide the account `sequence` and the `signingPublicKey` of the source
account of a `Transaction` at the time of construction, as well as a `fee`.
Here's an example of preparing the above payment:
<!-- MULTICODE_BLOCK_START -->
_JavaScript_
{{ include_code("_code-samples/send-xrp/send-xrp.js", start_with="// Prepare", end_before="// Sign", language="js" ) }}
_Python_
{{ include_code("_code-samples/send-xrp/send-xrp.py", start_with="# Prepare", end_before="# Sign", language="py" ) }}
_Java_
{{ include_code("_code-samples/send-xrp/SendXrp.java", start_with="// Prepare", end_before="// Sign", language="java") }}
<!-- MULTICODE_BLOCK_END -->
{{ start_step("Prepare") }}
<div class="input-group mb-3">
<div class="input-group-prepend">
<span class="input-group-text">Send: </span>
</div>
<input type="number" class="form-control" value="22" id="xrp-amount"
aria-label="Amount of XRP, as a decimal" aria-describedby="xrp-amount-label"
min=".000001" max="100000000000" step="any">
<div class="input-group-append">
<span class="input-group-text" id="xrp-amount-label"> XRP</span>
</div>
</div>
<button id="prepare-button" class="btn btn-primary previous-steps-required">Prepare
example transaction</button>
<div class="output-area"></div>
{{ end_step() }}
### {{n.next()}}. Sign the Transaction Instructions
Signing a transaction uses your credentials to authorize the transaction on your behalf. The input to this step is a completed set of transaction instructions (usually JSON), and the output is a binary blob containing the instructions and a signature from the sender.
- **JavaScript:** Use the [sign() method](rippleapi-reference.html#sign) to sign the transaction with ripple-lib. The first argument is a string version of the JSON transaction to sign.
- **Python:** Use the [xrpl.transaction.safe_sign_transaction() method](https://xrpl-py.readthedocs.io/en/latest/source/xrpl.transaction.html#xrpl.transaction.safe_sign_transaction) with a model and wallet object.
- **Java:** Use a [`SignatureService`](https://javadoc.io/doc/org.xrpl/xrpl4j-crypto-core/latest/org/xrpl/xrpl4j/crypto/signing/SignatureService.html) instance to sign the transaction. For this tutorial, use the [`SingleKeySignatureService`](https://javadoc.io/doc/org.xrpl/xrpl4j-crypto-bouncycastle/latest/org/xrpl/xrpl4j/crypto/signing/SingleKeySignatureService.html).
<!-- MULTICODE_BLOCK_START -->
_JavaScript_
{{ include_code("_code-samples/send-xrp/send-xrp.js",
start_with="// Sign", end_before="// Submit", language="js" ) }}
_Python_
{{ include_code("_code-samples/send-xrp/send-xrp.py",
start_with="# Sign", end_before="# Submit", language="py" ) }}
_Java_
{{ include_code("_code-samples/send-xrp/SendXrp.java",
start_with="// Sign", end_before="// Submit", language="java" ) }}
<!-- MULTICODE_BLOCK_END -->
The result of the signing operation is a transaction object containing a signature. Typically, XRP Ledger APIs expect a signed transaction to be the hexadecimal representation of the transaction's canonical [binary format](serialization.html), called a "blob".
- In ripple-lib, the signing API also returns the transaction's ID, or identifying hash, which you can use to look up the transaction later. This is a 64-character hexadecimal string that is unique to this transaction.
- In xrpl-py, you can get the transaction's hash in the response to submitting it in the next step.
- In xrpl4j, `SignatureService.sign` returns a `SignedTransaction`, which contains the transaction's hash, which you can use to look up the transaction later.
{{ start_step("Sign") }}
<button id="sign-button" class="btn btn-primary previous-steps-required">Sign
example transaction</button>
<div class="output-area"></div>
{{ end_step() }}
### {{n.next()}}. Submit the Signed Blob
Now that you have a signed transaction, you can submit it to an XRP Ledger server, and that server will relay it through the network. It's also a good idea to take note of the latest validated ledger index before you submit. The earliest ledger version that your transaction could get into as a result of this submission is one higher than the latest validated ledger when you submit it. Of course, if the same transaction was previously submitted, it could already be in a previous ledger. (It can't succeed a second time, but you may not realize it succeeded if you aren't looking in the right ledger versions.)
- **JavaScript:** Use the [submit() method](rippleapi-reference.html#submit) to submit a transaction to the network. Use the [`getLedgerVersion()` method](rippleapi-reference.html#getledgerversion) to get the latest validated ledger index.
- **Python:** Use the [xrpl.transaction.submit_transaction() method](https://xrpl-py.readthedocs.io/en/latest/source/xrpl.transaction.html#xrpl.transaction.submit_transaction) to submit a transaction to the network. Use the [xrpl.ledger.get_latest_validated_ledger_sequence() method](https://xrpl-py.readthedocs.io/en/latest/source/xrpl.ledger.html#xrpl.ledger.get_latest_validated_ledger_sequence) to get the latest validated ledger index.
- **Java:** Use the [XrplClient.submit(SignedTransaction>) method](https://javadoc.io/doc/org.xrpl/xrpl4j-client/latest/org/xrpl/xrpl4j/client/XrplClient.html) to submit a transaction to the network. Use the `XrplClient.ledger()` method to get the latest validated ledger index.
<!-- MULTICODE_BLOCK_START -->
_JavaScript_
{{ include_code("_code-samples/send-xrp/send-xrp.js", start_with="// Submit", end_before="// Wait", language="js" ) }}
_Python_
{{ include_code("_code-samples/send-xrp/send-xrp.py", start_with="# Submit", end_before="# Wait", language="py") }}
_Java_
{{ include_code("_code-samples/send-xrp/SendXrp.java", start_with="// Submit", end_before="// Wait", language="java" ) }}
<!-- MULTICODE_BLOCK_END -->
This method returns the **tentative** result of trying to apply the transaction to the open ledger. This result _can_ change when the transaction is included in a validated ledger: transactions that succeed initially might ultimately fail, and transactions that fail initially might ultimately succeed. Still, the tentative result often matches the final result, so it's OK to get excited if you see `tesSUCCESS` here. 😁
If you see any other result, you should check the following:
- Are you using the correct addresses for the sender and destination?
- Did you forget any other fields of the transaction, skip any steps, or make any other typos?
- Do you have enough Test Net XRP to send the transaction? The amount of XRP you can send is limited by the [reserve requirement](reserves.html), which is currently 20 XRP with an additional 5 XRP for each "object" you own in the ledger. (If you generated a new address with the Test Net Faucet, you don't own any objects.)
- Are you connected to a server on the test network?
See the full list of [transaction results](transaction-results.html) for more possibilities.
{{ start_step("Submit") }}
<button id="submit-button" class="btn btn-primary previous-steps-required" data-tx-blob-from="#signed-tx-blob" data-wait-step-name="Wait">Submit
example transaction</button>
<div class="loader collapse"><img class="throbber" src="assets/img/xrp-loader-96.png"> Sending...</div>
<div class="output-area"></div>
{{ end_step() }}
### {{n.next()}}. Wait for Validation
Most transactions are accepted into the next ledger version after they're submitted, which means it may take 4-7 seconds for a transaction's outcome to be final. If the XRP Ledger is busy or poor network connectivity delays a transaction from being relayed throughout the network, a transaction may take longer to be confirmed. (For more information on expiration of unconfirmed transactions, see [Reliable Transaction Submission](reliable-transaction-submission.html).)
- **JavaScript:** Use an account [subscription](rippleapi-reference.html#listening-to-streams) to listen for an event when the transaction is confirmed. Use the `ledger` event type to trigger your code to run whenever there is a new validated ledger version so that you can know if the transaction can no longer be confirmed.
- **Python:** Poll the [xrpl.transaction.get_transaction_from_hash() method](https://xrpl-py.readthedocs.io/en/latest/source/xrpl.transaction.html#xrpl.transaction.get_transaction_from_hash) to see if your transaction has a final result. Periodically use the [xrpl.ledger.get_latest_validated_ledger_sequence() method](https://xrpl-py.readthedocs.io/en/latest/source/xrpl.ledger.html#xrpl.ledger.get_latest_validated_ledger_sequence) so you can know if the transaction can no longer be confirmed.
**Tip:** The [xrpl.transaction.send_reliable_submission() method](https://xrpl-py.readthedocs.io/en/latest/source/xrpl.transaction.html#xrpl.transaction.send_reliable_submission) handles this process all in one call. You can use this instead of `submit_transaction()` wherever it's appropriate for your code to stop and wait for a transaction's [final result](finality-of-results.html) to be confirmed.
- **Java** Poll the [XrplClient.transaction() method](https://javadoc.io/doc/org.xrpl/xrpl4j-client/latest/org/xrpl/xrpl4j/client/XrplClient.html) to see if your transaction has a final result. Periodically check that the latest validated ledger index has not passed the `LastLedgerIndex` of the transaction using the `XrplClient.ledger()` method.
<!-- MULTICODE_BLOCK_START -->
_JavaScript_
{{ include_code("_code-samples/send-xrp/send-xrp.js", start_with="// Wait", end_before="// There are other", language="js" ) }}
_Python_
{{ include_code("_code-samples/send-xrp/send-xrp.py", start_with="# Wait", end_before="# Check", language="py") }}
_Java_
{{ include_code("_code-samples/send-xrp/SendXrp.java", start_with="// Wait", end_before="// Check", language="java" ) }}
<!-- MULTICODE_BLOCK_END -->
{{ start_step("Wait") }}
{% include '_snippets/interactive-tutorials/wait-step.md' %}
{{ end_step() }}
### {{n.next()}}. Check Transaction Status
To know for sure what a transaction did, you must look up the outcome of the transaction when it appears in a validated ledger version.
- **JavaScript:** Use the [`getTransaction()` method](rippleapi-reference.html#gettransaction) to check the status of a transaction.
- **Python:** The response of [xrpl.transaction.get_transaction_from_hash() method](https://xrpl-py.readthedocs.io/en/latest/source/xrpl.transaction.html#xrpl.transaction.get_transaction_from_hash) contains the results if the transaction has been validated by consensus. (See [tx result](https://xrpl.org/tx.html#response-format) for a detailed reference of the fields this can contain.)
- **Java:** Use the `XrplClient.transaction()` method to check the status of a transaction.
<!-- MULTICODE_BLOCK_START -->
_JavaScript_
{{ include_code("_code-samples/send-xrp/send-xrp.js", start_with="// Check", language="js" ) }}
_Python_
{{ include_code("_code-samples/send-xrp/send-xrp.py", start_with="# Check", language="py") }}
_Java_
{{ include_code("_code-samples/send-xrp/SendXrp.java", start_with="// Check", language="java" ) }}
<!-- MULTICODE_BLOCK_END -->
The RippleAPI `getTransaction()` method only returns success if the transaction is in a validated ledger version. Otherwise, the `await` expression raises an exception.
**Caution:** Other APIs, including xrpl-py, may return tentative results from ledger versions that have not yet been validated. For example, if you use the `rippled` APIs' [tx method][], be sure to look for `"validated": true` in the response to confirm that the data comes from a validated ledger version. Transaction results that are not from a validated ledger version are subject to change. For more information, see [Finality of Results](finality-of-results.html).
{{ start_step("Check") }}
<button id="get-tx-button" class="btn btn-primary previous-steps-required">Check transaction status</button>
<div class="output-area"></div>
{{ end_step() }}
## Differences for Production
To send an XRP payment on the production XRP Ledger, the steps you take are largely the same. However, there are some key differences in the necessary setup:
- [Getting real XRP isn't free.](#getting-a-real-xrp-account)
- [You must connect to a server that's synced with the production XRP Ledger network.](#connecting-to-the-production-xrp-ledger)
### Getting a Real XRP Account
This tutorial uses a button to get an address that's already funded with Test Net XRP, which only works because Test Net XRP is not worth anything. For actual XRP, you need to get XRP from someone who already has some. (For example, you might buy it on an exchange.) You can generate an address and secret that'll work on either production or the Testnet as follows:
<!-- MULTICODE_BLOCK_START -->
_JavaScript_
```js
const generated = api.generateAddress()
console.log(generated.address) // Example: rGCkuB7PBr5tNy68tPEABEtcdno4hE6Y7f
console.log(generated.secret) // Example: sp6JS7f14BuwFY8Mw6bTtLKWauoUs
```
_Python_
```py
from xrpl.wallet import Wallet
my_wallet = Wallet.create()
print(my_wallet.classic_address) # Example: rGCkuB7PBr5tNy68tPEABEtcdno4hE6Y7f
print(my_wallet.seed) # Example: sp6JS7f14BuwFY8Mw6bTtLKWauoUs
```
_Java_
```java
WalletFactory walletFactory = DefaultWalletFactory.getInstance();
SeedWalletGenerationResult generationResult = walletFactory.randomWallet(false);
Wallet wallet = generationResult.wallet();
System.out.println(wallet.classicAddress()); // Example: rGCkuB7PBr5tNy68tPEABEtcdno4hE6Y7f
System.out.println(generationResult.seed()); // Example: sp6JS7f14BuwFY8Mw6bTtLKWauoUs
```
<!-- MULTICODE_BLOCK_END -->
**Warning:** You should only use an address and secret that you generated securely, on your local machine. If another computer generated the address and secret and sent it to you over a network, it's possible that someone else on the network may see that information. If they do, they'll have as much control over your XRP as you do. It's also recommended not to use the same address for the Testnet and Mainnet, because transactions that you created for use on one network could potentially also be viable on the other network, depending on the parameters you provided.
Generating an address and secret doesn't get you XRP directly; you're only choosing a random number. You must also receive XRP at that address to [fund the account](accounts.html#creating-accounts). A common way to acquire XRP is to buy it from an [exchange](exchanges.html), then withdraw it to your own address.
### Connecting to the Production XRP Ledger
When you instantiate the `RippleAPI` object, you must specify a server that's synced with the appropriate XRP Ledger. For many cases, you can use Ripple's public servers, such as in the following snippet:
<!-- MULTICODE_BLOCK_START -->
_JavaScript_
```js
ripple = require('ripple-lib')
api = new ripple.RippleAPI({server: 'wss://xrplcluster.com'})
api.connect()
```
_Python_
```py
from xrpl.clients import JsonRpcClient
mainnet_url = "https://xrplcluster.com"
client = JsonRpcClient(mainnet_url)
```
_Java_
```java
final HttpUrl rippledUrl = HttpUrl.get("https://xrplcluster.com");
XrplClient xrplClient = new XrplClient(rippledUrl);
```
<!-- MULTICODE_BLOCK_END -->
If you [install `rippled`](install-rippled.html) yourself, it connects to the production network by default. (You can also [configure it to connect to the test net](connect-your-rippled-to-the-xrp-test-net.html) instead.) After the server has synced (typically within about 15 minutes of starting it up), you can connect to it locally, which has [various benefits](the-rippled-server.html). The following example shows how to connect to a server running the default configuration:
<!-- MULTICODE_BLOCK_START -->
_JavaScript_
```js
ripple = require('ripple-lib')
api = new ripple.RippleAPI({server: 'ws://localhost:6006'})
api.connect()
```
_Python_
```py
from xrpl.clients import JsonRpcClient
mainnet_url = "http://localhost:5005"
client = JsonRpcClient(mainnet_url)
```
_Java_
```java
final HttpUrl rippledUrl = HttpUrl.get("http://localhost:5005");
XrplClient xrplClient = new XrplClient(rippledUrl);
```
<!-- MULTICODE_BLOCK_END -->
**Tip:** The local connection uses an unencrypted protocol (`ws` or `http`) rather than the TLS-encrypted version (`wss` or `https`). This is secure only because the communications never leave the same machine, and is easier to set up because it does not require a TLS certificate. For connections on an outside network, always use `wss` or `https`.
## Next Steps
After completing this tutorial, you may want to try the following:
- Build [Reliable transaction submission](reliable-transaction-submission.html) for production systems.
- Consult [RippleAPI JavaScript Reference](rippleapi-reference.html), [xrpl-py Python Reference](https://xrpl-py.readthedocs.io/), or [xrpl4j Javadocs](https://javadoc.io/doc/org.xrpl/) for the full range of XRP Ledger functionality.
- Customize your [Account Settings](manage-account-settings.html).
- Learn how [Transaction Metadata](transaction-metadata.html) describes the outcome of a transaction in detail.
- Explore more [Payment Types](payment-types.html) such as Escrows and Payment Channels.
- Read best practices for [XRP Ledger Businesses](xrp-ledger-businesses.html).
<!--{# common link defs #}-->
{% include '_snippets/rippled-api-links.md' %}
{% include '_snippets/tx-type-links.md' %}
{% include '_snippets/rippled_versions.md' %}