Hi Andreas,
Thanks for the information! At this point, I guess the solution will be
write some code manually that will connect transaction inputs and outputs
together to calculate those fields, which hopefully shouldn't be super
painful.
Sidd
On Wednesday, March 22, 2017 at 5:42:21 PM UTC-4, Andreas Schildbach wrote:
>
> Welcome to bitcoinj!
>
> The input values and the fee is only known for transactions that were
> created by bitcoinj's Wallet (which you're likely not using anyway). For
> incoming transactions there values are missing, it's a known limitation
> of the Bitcoin protocol.
>
> Yes, MemoryBlockStore only stores headers. Afaik there is no block store
> in bitcoinj that actually stores the transactions. Bitcoinj is mainly
> designed for wallets and as a wallet you'd only keep what's relevant to
> you.
>
>
> On 03/22/2017 08:46 PM, Sidd S wrote:
> > I am new to BitcoinJ, but it seems like a good tool for building Java
> > applications around Bitcoin. I am trying to use BitcoinJ to try and
> > parse information from the blockchain. A lot of fields are pretty easy
> > to fetch, but I can't seem to get a couple of things.
> >
> > I'll provide some code below that I have written just to kind of give
> > some context as to the types of things I have been trying. As a note, I
> > am using Scala for this, but hopefully the code should be somewhat
> > intuitive.
> >
> > |
> > // importing too many things
> > import org.bitcoinj.core._
> > import org.bitcoinj.params._
> > import org.bitcoinj.utils._
> > import org.bitcoinj.store._
> > import java.io.File
> > import java.util.ArrayList
> >
> > // init
> > val params = new MainNetParams()
> > new Context(params)
> >
> > // load the blockchain files..only loading the first .dat file
> > val files = new ArrayList[File]()
> > files.add(new File("blk00000.dat"))
> > val bfl = new BlockFileLoader(params, files)
> >
> > // this line will create an array of the first 10,000 blocks
> > val b = (1 to 10000).map(_ => bfl.next)
> >
> > // trying to inspect a transaction..the outputs are below
> > val ts = b(3888).getTransactions
> > val t = ts.get(10)
> > t.getFee
> > // res34: org.bitcoinj.core.Coin = null
> > t.getInputSum
> > // res35: org.bitcoinj.core.Coin = 0
> > |
> >
> > It makes sense that I am unable to get the fee or input sum of the 10th
> > transaction of the 3889th block because it doesn't have a link to the
> > previous transactions. How can I add these links so I can use
> > functionality like getFee and getInputSum?
> >
> > I have tried to create a MemoryBlockStore object and BlockChain object
> > in hopes that these would link up the transactions, but apparently
> > StoredBlocks only store the headers of blocks but not the transactions
> > themselves. so I am unable to access them.
> >
> > Does anyone have any idea how I can accomplish this?
> >
> > --
> > You received this message because you are subscribed to the Google
> > Groups "bitcoinj" group.
> > To unsubscribe from this group and stop receiving emails from it, send
> > an email to bitcoinj+u...@googlegroups.com <javascript:>
> > <mailto:bitcoinj+u...@googlegroups.com <javascript:>>.
> > For more options, visit https://groups.google.com/d/optout.
>
>
>
--
You received this message because you are subscribed to the Google Groups
"bitcoinj" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to bitcoinj+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
