<p>If you are developing in java using the bitcoinj library, they have a mechanism in place to do it without downloading the full block chain. They just download the header lightweight simplified payment verification (SPV) mode. Maybe you can try that.This is the <a href="https://bitcoinj.github.io/" rel="nofollow">link</a>.</p>

<pre><code>    SendRequest req;
    Transaction transaction = null;

   transaction = new Transaction(networkParameters);

   // the following statement will help to create an OP_RETURN with "Test" as the message
   transaction.addOutput(Coin.ZERO, ScriptBuilder.createOpReturnScript("Test".toString().getBytes()));
   req = SendRequest.forTx(transaction);
</code></pre>

CC BY-SA 3.0
2016-06-17T04:30:42.160Z
This library can be used for testnet transactions?
Anjelo
CC BY-SA 3.0
2016-06-17T10:41:04.147Z
Yes you can do it for `testnet`,`mainnet` or `regtest` networks
jgm
CC BY-SA 3.0
2016-06-16T11:24:36.503Z
2016-06-16T11:24:36.503Z
jgm
<p>I would like to do a bitcoin transaction in testnet by embedding a custom message in the OP_RETURN. do i have to download the bitcoin core client with and the block chain to do that? or can i use a separate way without downloading the whole blockchain? Thanks!  </p>

<blockchain><testnet><op-return>
OP_RETURN custom message in testnet transaction
Anjelo
# OP_RETURN custom message in testnet transaction

(Asked by: username_0 on 2016-06-16)

I would like to do a bitcoin transaction in testnet by embedding a custom message in the OP\_RETURN. do i have to download the bitcoin core client with and the block chain to do that? or can i use a separate way without downloading the whole blockchain? Thanks!

**Tags:** blockchain, testnet, op-return


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## 1 answers

### Answer by username_1 on 2016-06-16. Score: 1

If you are developing in java using the bitcoinj library, they have a mechanism in place to do it without downloading the full block chain. They just download the header lightweight simplified payment verification (SPV) mode. Maybe you can try that.This is the [link](https://bitcoinj.github.io/).

```
    SendRequest req;
    Transaction transaction = null;

   transaction = new Transaction(networkParameters);

   // the following statement will help to create an OP_RETURN with "Test" as the message
   transaction.addOutput(Coin.ZERO, ScriptBuilder.createOpReturnScript("Test".toString().getBytes()));
   req = SendRequest.forTx(transaction);

```

> **Comments:**
> **username_0**: This library can be used for testnet transactions?  
> **username_1**: Yes you can do it for `testnet`,`mainnet` or `regtest` networks  

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