title: Best way to create multiple LinkedLists of Hashmaps with multiple keys and values?
body: <p>So the title does a terrible job at explaining what I mean, so let me explain.</p>
  <p>So I basically want to make a mini cryptocurrency blockchain as a project. I'm trying to think of the best thing to use as the blocks in a blockchain. I'd need the blocks to hold the header information which is the following:</p>
  <p>Previous Blocks Hash. Timestamp. Difficulty Target. Nonce. Version. Merkle Root.</p>
  <p>And then the transactions that are also contained within each block. All in all the block would end up looking like this.</p>
  <p><a href="https://i.stack.imgur.com/2rRhT.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/2rRhT.png" alt="enter image description here" /></a></p>
  <p>I thought a Hashmap would be the best way to do this as you can assign each of the above keys a value, but I'm not sure how I'd go about it. I would need a list that held the Hashmaps which held multiple keys and values, but I'd also need the list to hold whatever the transactions would be held in. I'd also need the next list to be able to see the previous list (so it can get the hash from everything in its header).</p>
  <p>Could anyone give me some advice on the best way to deal with this? Been thinking it over for the last few days but I don't think I'm coming any closer to an answer.</p>
  <p>Thank you.</p>