Java addblockchain more

pom.xml

@@ -51,11 +51,8 @@
 
 		<!-- For cryptocurrencies tests and tutorials -->
 		<!-- https://mvnrepository.com/artifact/com.google.code.gson/gson -->
-		<dependency>
-			<groupId>com.google.code.gson</groupId>
-			<artifactId>gson</artifactId>
-			<version>2.8.8</version>
-		</dependency>
+		<!-- <dependency> <groupId>com.google.code.gson</groupId> <artifactId>gson</artifactId> 
+			<version>2.8.8</version> </dependency> -->
 		<!-- https://mvnrepository.com/artifact/org.bouncycastle/bcprov-jdk15to18 -->
 		<dependency>
 			<groupId>org.bouncycastle</groupId>

src/main/java/gabywald/crypto/blockchain/Block.java

@@ -5,13 +5,17 @@
 import java.util.List;
 import java.util.Map;
 
+import gabywald.global.json.JSONException;
+import gabywald.global.json.JSONValue;
+import gabywald.global.json.JSONifiable;
+
 /**
  * Block of BlockChain. 
  * <br/><a href="https://medium.com/programmers-blockchain/create-simple-blockchain-java-tutorial-from-scratch-6eeed3cb03fa">https://medium.com/programmers-blockchain/create-simple-blockchain-java-tutorial-from-scratch-6eeed3cb03fa</a>
  * <br/><a href="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/CryptoKass/NoobChain-Tutorial-Part-1">https://github.com/CryptoKass/NoobChain-Tutorial-Part-1</a>
  * @author Gabriel Chandesris (2021)
  */
-public class Block {
+public class Block extends JSONifiable {
 
 	private String hash;
 	private String previousHash; 
@@ -52,19 +56,12 @@ public Block(String previousHash ) {
 	 * @see StringUtils#applySha256(String)
 	 */
 	public String calculateHash() {
-		String calculatedhash = null;
-		try {
-			calculatedhash = StringUtils.applySha256( 
+		String calculatedhash = StringUtils.applySha256( 
 					previousHash +
 					Long.toString(timeStamp) +
 					Integer.toString(nonce) + 
 					merkleRoot
 					);
-		} catch (BlockchainException e) {
-			// e.printStackTrace();
-			System.out.println( e.getMessage() );
-			calculatedhash = null;
-		}
 		return calculatedhash;
 	}
 
@@ -120,4 +117,31 @@ public List<Transaction> getTransactions()
 		{ return this.transactions; }
 
 
+	@Override
+	protected void setKeyValues() {
+		this.put("hash", JSONValue.instanciate( this.hash.toString() ) );
+		this.put("previousHash", JSONValue.instanciate( this.previousHash.toString() ) );
+		this.put("timeStamp", JSONValue.instanciate( this.timeStamp ) );
+		this.put("nonce", JSONValue.instanciate( this.nonce ) );
+		this.put("transactions", JSONifiable.generateArray( this.transactions ) );
+	}
+
+	@Override
+	protected <T extends JSONifiable> T reloadFrom(String json) 
+			throws JSONException {
+		return null;
+	}
+
+	@Override
+	public String toString() {
+		StringBuilder sbToReturn = new StringBuilder();
+		sbToReturn.append("hash").append(": ").append( this.hash.toString() ).append("\n");
+		sbToReturn.append("previousHash").append(": ").append( this.previousHash.toString() ).append("\n");
+		sbToReturn.append("timeStamp").append(": ").append( this.timeStamp ).append("\n");
+		sbToReturn.append("transactions").append(": \n");
+		for (Transaction transaction : this.transactions) {
+			sbToReturn.append("\t transaction").append(": ").append( transaction.toString() ).append("\n");
+		}
+		return sbToReturn.toString();
+	}
 }

src/main/java/gabywald/crypto/blockchain/BlockChain.java

@@ -8,7 +8,7 @@
  * 
  * @author Gabriel Chandesris (2021)
  */
-public abstract class BlockChain {
+public class BlockChain {
 
 	/**
 	 * Build a list of Blocks. 
@@ -141,4 +141,5 @@ public static boolean addBlock(final List<Block> blockchain, final Block newBloc
 		newBlock.mineBlock(difficulty);
 		return blockchain.add(newBlock);
 	}
+
 }

src/main/java/gabywald/crypto/blockchain/NoobChainTests.java

@@ -8,7 +8,9 @@
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
-import com.google.gson.GsonBuilder;
+// import com.google.gson.GsonBuilder;
+
+import gabywald.global.json.JSONifiable;
 
 /**
  * Tests about BlockChain / NoobChain. 
@@ -48,9 +50,13 @@ void testPart02() {
 		blockchain.add(new Block("Yo im the second block", blockchain.get(blockchain.size()-1).getHash() )); 
 		blockchain.add(new Block("Hey im the third block",  blockchain.get(blockchain.size()-1).getHash() ));
 		Assertions.assertEquals(3,  blockchain.size());
-		String blockchainJson = new GsonBuilder().setPrettyPrinting().create().toJson(blockchain);
-		Assertions.assertNotNull( blockchainJson );
+
+		String blockchainJson = JSONifiable.generateArray( blockchain ).toString(); 
+		// String blockchainJson = new GsonBuilder().setPrettyPrinting().create().toJson(blockchain);
+		System.out.println("\nThe block chain: ");
 		System.out.println(blockchainJson);
+
+		// for (Block block : blockchain) { System.out.println( block ); }
 	}
 
 	@Test
@@ -76,12 +82,12 @@ void testPart03() {
 
 		Assertions.assertTrue( BlockChain.isChainValidV1( blockchain ) );
 
-		String blockchainJson = new GsonBuilder().setPrettyPrinting().create().toJson(blockchain);
-
-		Assertions.assertNotNull( blockchainJson );
-
+		String blockchainJson = JSONifiable.generateArray( blockchain ).toString(); 
+		// String blockchainJson = new GsonBuilder().setPrettyPrinting().create().toJson(blockchain);
 		System.out.println("\nThe block chain: ");
 		System.out.println(blockchainJson);
+
+		// for (Block block : blockchain) { System.out.println( block ); }
 	}
 
 	@Test
@@ -188,8 +194,9 @@ void testPart05() {
 
 		Block block3 = new Block(block2.getHash() );
 		System.out.println("\nWalletB is Attempting to send funds (20) to WalletA...");
-		boolean bBlock3AddTransactionResult = block3.addTransaction(	walletB.sendFunds( walletA.getPublicKey(), 20, mapUTXOs), 
+		boolean bBlock3AddTransactionResult = block3.addTransaction(	walletB.sendFunds( walletA.getPublicKey(), 20f, mapUTXOs), 
 																		mapUTXOs, minimumTransaction);
+
 		Assertions.assertTrue( bBlock3AddTransactionResult );
 		System.out.println("\nWalletA's balance is: " + walletA.getBalance( mapUTXOs ));
 		System.out.println("WalletB's balance is: " + walletB.getBalance( mapUTXOs ));

src/main/java/gabywald/crypto/blockchain/StringUtils.java

@@ -28,13 +28,10 @@ public abstract class StringUtils {
 	 * Applies Sha256 to a string and returns the result. 
 	 * @param input
 	 * @return (String)
-	 * @throws BlockchainException 
-	 * TODO upgrade / improve this method (applySha256) to return null value if any exception inside !
 	 */
-	public static String applySha256(String input) 
-			throws BlockchainException {		
+	public static String applySha256(String input)  {		
 		try {
-			MessageDigest digest = MessageDigest.getInstance("SHA-256");	        
+			MessageDigest digest = MessageDigest.getInstance("SHA-256");
 			// Applies sha256 to our input, 
 			byte[] hash = digest.digest(input.getBytes("UTF-8"));
 			// This will contain hash as hexidecimal
@@ -49,7 +46,8 @@ public static String applySha256(String input)
 			return hexString.toString();
 		} catch (NoSuchAlgorithmException | UnsupportedEncodingException e) {
 			System.out.println( "StringUtils: " + e.getClass().getName() + ": " + e.getMessage() );
-			throw new BlockchainException("StringUtils: " + e.getClass().getName() +": " + e.getMessage());
+			// throw new BlockchainException("StringUtils: " + e.getClass().getName() +": " + e.getMessage());
+			return null;
 		}
 	}
 
@@ -140,11 +138,9 @@ public static String getMerkleRoot(List<Transaction> transactions) {
 		while (count > 1) {
 			treeLayer = new ArrayList<String>();
 			for (int i = 1 ; i < previousTreeLayer.size() ; i++) {
-				try {
-					treeLayer.add(StringUtils.applySha256(previousTreeLayer.get(i-1) + previousTreeLayer.get(i)));
-				} catch (BlockchainException e) {
-					System.out.println( e.getMessage() );
-				}
+				String calculedHash = StringUtils.applySha256(previousTreeLayer.get(i-1) + previousTreeLayer.get(i));
+				if (calculedHash != null) 
+					{ treeLayer.add( calculedHash ); }
 			}
 			count = treeLayer.size();
 			previousTreeLayer = treeLayer;

src/main/java/gabywald/crypto/blockchain/Transaction.java

@@ -7,6 +7,11 @@
 
 import java.util.List;
 import java.util.Map;
+
+import gabywald.global.json.JSONException;
+import gabywald.global.json.JSONValue;
+import gabywald.global.json.JSONifiable;
+
 import java.util.ArrayList;
 import java.util.Base64;
 
@@ -16,7 +21,7 @@
  * <br/><a href="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/CryptoKass/NoobChain-Tutorial-Part-2">https://github.com/CryptoKass/NoobChain-Tutorial-Part-2</a>
  * @author Gabriel Chandesris (2021)
  */
-public class Transaction {
+public class Transaction extends JSONifiable {
 	/** This is also the hash of the transaction. */
 	private String transactionId;
 	/** senders address/public key. */
@@ -48,17 +53,11 @@ public Transaction(PublicKey from, PublicKey to, float value,  List<TransactionI
 	private String calculateHash() {
 		// Increase the sequence to avoid 2 identical transactions having the same hash
 		Transaction.sequence++;
-		try {
-			return StringUtils.applySha256(
-					StringUtils.getStringFromKey(this.sender) +
-					StringUtils.getStringFromKey(this.recipient) +
-					Float.toString(value) + Transaction.sequence
-					);
-		} catch (BlockchainException e) {
-			// e.printStackTrace();
-			System.out.println( e.getMessage() );
-			return null;
-		}
+		return StringUtils.applySha256(
+				StringUtils.getStringFromKey(this.sender) +
+				StringUtils.getStringFromKey(this.recipient) +
+				Float.toString(value) + Transaction.sequence
+				);
 	}
 
 	/** 
@@ -212,8 +211,6 @@ public float getOutputsValue() {
 		return total;
 	}
 
-
-
 	public void setTransactionId(String transactionId) 
 		{ this.transactionId = transactionId; }
 
@@ -235,4 +232,30 @@ public List<TransactionOutput> getOutputs()
 	public List<TransactionInput> getInputs() 
 		{ return this.inputs; }
 
+	@Override
+	protected void setKeyValues() {
+		this.put("transactionId", JSONValue.instanciate( this.transactionId.toString() ) );
+		this.put("sender", JSONValue.instanciate( this.sender.toString() ) );
+		this.put("recipient", JSONValue.instanciate( this.recipient.toString() ) );
+		this.put("value", JSONValue.instanciate( this.value ) );
+		// this.put("signature", JSONValue.instanciate( this.signature ) );
+		// this.put("sequence", JSONValue.instanciate( this.sequence ) );
+	}
+
+	@Override
+	protected <T extends JSONifiable> T reloadFrom(String json) 
+			throws JSONException {
+		return null;
+	}
+
+	@Override
+	public String toString() {
+		StringBuilder sbToReturn = new StringBuilder();
+		sbToReturn.append("transactionId").append(": ").append( this.transactionId.toString() ).append("\n");
+		sbToReturn.append("sender").append(": ").append( this.sender.toString() ).append("\n");
+		sbToReturn.append("recipient").append(": ").append( this.recipient ).append("\n");
+		sbToReturn.append("value").append(": ").append( this.value ).append("\n");
+		return sbToReturn.toString();
+	}
+
 }

src/main/java/gabywald/crypto/blockchain/TransactionOutput.java

@@ -27,15 +27,9 @@ public TransactionOutput(PublicKey reciepient, float value, String parentTransac
 		this.recipient = reciepient;
 		this.value = value;
 		this.parentTransactionId = parentTransactionId;
-		try {
-			this.id = StringUtils.applySha256(StringUtils.getStringFromKey(reciepient) 
-					+ Float.toString(value) + parentTransactionId);
-			// TODO check alternatives for here when exception occurs !! (builder ?) : see StringUtils.applySha256 comment !
-		} catch (BlockchainException e) {
-			// e.printStackTrace();
-			System.out.println(e.getMessage());
-			this.id = null;
-		}
+
+		this.id = StringUtils.applySha256(StringUtils.getStringFromKey(reciepient) 
+				+ Float.toString(value) + parentTransactionId);
 	}
 
 	/**