Ethereum: How do I create an offline transaction in java to broadcast via blockchain.info?

Creation of offline transactions on the Ethereum blockchain using Java and Pushtx API

The Blockchain Ethereum is a decentralized, public and safe platform for the conservation and transmission of transactions. One of its key features is the possibility of creating and transmitting offline transactions via Pushtx APIs from external applications, such as mobile app or web clients. In this article, we will explore how to create an offline in java transaction that can be transmitted to the Ethereum blockchain using using Pushtx API.

Background

Pushtx API allows developers to send raw transactions to a node on the Ethereum network without waiting for the transaction to be verified by a peer (i.e. another node). This allows you to create and transmit offline transactions from external applications. To use the Pushtx API, you need to obtain an Ethereum portfolio address that is not already used as a wallet.

Choose between Bitcoinj and Pushtx

There are two popular libraries to interact with the Ethereum Blockchain in Java: Bitcoinj and Pushtx. Here is a short comparison:

* Bitcoinj : a complete cryptocurrency client bookcase that allows you to interact with the Ethereum blockchain using various protocols (e.g. Json-RPC, http). However, it requires a wallet address and is not designed specifically for offline transactions.

* Pushtx : a library developed by Infura, a cloud -based infrastructure supplier to interact with the Ethereum network. Pushtx provides a simple bees for creating and sending raw transactions to the nodes on the Ethereum network.

For this example, we will use Pushtx.

Creation of an offline transaction in Java

To create an offline transaction using Pushtx, it is necessary:

• Create a new instance of the Pushtx class:

`Java

import com.infura.pushtx.pushtx;

import com.infura.pushtx.pushtransation;

Public class offlinetransationxample {

Public Static Void Main (String [] Args) {

// Set the URL of the Ethereum node (for example, “

String Nodeurl = “

// Create a new application for the Pushtx class

Pushtx Pushtx = New Pushtx (Nodeurl);

}

}

`

• Sets the "wallet" on an Ethereum portfolio address that is not already used as a portfolio:

Java

// Set your Ethereum portfolio address

String walletaddres = “0xyour_wallet_address”;

`

• Create a new application for thePushtransation ‘class:

`Java

// Create a new Pushtransation object

Pushtransation Transaction = Pushtx.CreateTransation (

New string [] {“0x1234567890Abcdef”, “Transaction data”})

);

`

Sign the offline transaction

To sign the offline transaction, it is necessary to use thesignmessage class’ Pushtx:

Java

// Sign the transaction using the private key

String Signedtransation = Pushtx.signransation (Transaction, New String [] {“Your_private_key”});

`

By transmitting the offline transaction

Once the offline transaction has been created and signed, you can transmit it to the Ethereum network using the Pustx API. Here is an example of how to do it:

Java

// Create a new application of the Pushtx class with the same URL node and the wallet address

Pushtx Pushtx = New Pushtx (Nodeurl);

// Sets the transaction signed as payload for transmission

String payload = phymansation;

// transmits the transaction using the Pushtx API

Pushtx.brodcast (Payload, New String [] {“0x1234567890Abcdef”, “Your transaction data”});

`

Code samples

Here is an example of an example code that shows how to use the steps above:

Java

import com.infura.pushtx.pushtx;

import com.infura.pushtx.pushtransation;

Public class offlinetransationxample {

Public Static Void Main (String [] Args) {

// Set the URL of the Ethereum node (e.g.

MONERO ZCASH CONSCIOUS INVESTORS