Custom exceptions and testing

.gitignore

@@ -1,3 +1,61 @@
-/out/production/blockchain/
-/.idea/
-/blockchain.iml
+/.idea/.gitignore
+/build/reports/tests/test/css/base-style.css
+/build/classes/java/main/model/Block.class
+/out/production/blockchain_gitea/model/Block.class
+/build/classes/java/main/model/BlockChain.class
+/out/production/blockchain_gitea/model/BlockChain.class
+/blockChain.txt
+/build/classes/java/test/BlockChainTest.class
+/build/reports/tests/test/classes/BlockChainTest.html
+/.gradle/buildOutputCleanup/buildOutputCleanup.lock
+/.gradle/buildOutputCleanup/cache.properties
+/.gradle/checksums/checksums.lock
+/.idea/compiler.xml
+/build/reports/tests/test/packages/default-package.html
+/.gradle/7.1/dependencies-accessors/dependencies-accessors.lock
+/.gradle/7.1/executionHistory/executionHistory.lock
+/.gradle/7.1/fileHashes/fileHashes.lock
+/build/classes/java/main/util/FileManagement.class
+/out/production/blockchain_gitea/util/FileManagement.class
+/.gradle/7.1/dependencies-accessors/gc.properties
+/.gradle/7.1/gc.properties
+/.gradle/vcs-1/gc.properties
+/.idea/gradle.xml
+/gradle/wrapper/gradle-wrapper.jar
+/gradle/wrapper/gradle-wrapper.properties
+/gradlew
+/gradlew.bat
+/build/classes/java/main/util/HashFunction.class
+/out/production/blockchain_gitea/util/HashFunction.class
+/build/reports/tests/test/index.html
+/.idea/sonarlint/issuestore/index.pb
+/.idea/jarRepositories.xml
+/.gradle/7.1/fileChanges/last-build.bin
+/build/classes/java/main/Main.class
+/out/production/blockchain_gitea/Main.class
+/build/classes/java/main/model/Miner.class
+/out/production/blockchain_gitea/model/Miner.class
+/.idea/misc.xml
+/build/classes/java/main/exceptions/NoSelfTransactionException.class
+/build/classes/java/main/exceptions/NotEnoughCoinsException.class
+/out/production/blockchain_gitea/exceptions/NotEnoughCoinsException.class
+/build/test-results/test/binary/output.bin
+/build/test-results/test/binary/output.bin.idx
+/build/tmp/compileJava/previous-compilation-data.bin
+/build/tmp/compileTestJava/previous-compilation-data.bin
+/KeyPair/privateKey
+/.idea/inspectionProfiles/Project_Default.xml
+/KeyPair/publicKey
+/build/reports/tests/test/js/report.js
+/build/test-results/test/binary/results.bin
+/.idea/runConfigurations.xml
+/build/classes/java/main/util/Security.class
+/out/production/blockchain_gitea/util/Security.class
+/build/reports/tests/test/css/style.css
+/build/test-results/test/TEST-BlockChainTest.xml
+/build/classes/java/main/model/Transaction.class
+/out/production/blockchain_gitea/model/Transaction.class
+/build/classes/java/main/util/TransactionsGenerator.class
+/out/production/blockchain_gitea/util/TransactionsGenerator.class
+/.idea/uiDesigner.xml
+/.idea/vcs.xml

src/main/java/exceptions/NoSelfTransactionException.java

@@ -0,0 +1,9 @@
+package exceptions;
+
+public class NoSelfTransactionException extends RuntimeException {
+
+  public NoSelfTransactionException(final String username) {
+    super(username + " tried to send coins to oneself");
+  }
+
+}

src/main/java/model/BlockChain.java

@@ -1,5 +1,6 @@
 package model;
 
+import exceptions.NoSelfTransactionException;
 import java.io.IOException;
 import java.io.Serializable;
 import java.security.InvalidKeyException;
@@ -94,7 +95,9 @@ public class BlockChain implements Serializable {
       InvalidKeySpecException,
       NotEnoughCoinsException
   {
-    if (usersCoins.get(sender) <= 0 || usersCoins.get(sender) < amount) {
+    if (sender.equals(receiver)) {
+      throw new NoSelfTransactionException(sender);
+    } else if (usersCoins.get(sender) <= 0 || usersCoins.get(sender) < amount) {
       throw new NotEnoughCoinsException(sender);
     } else {
       transferCoins(sender, amount, receiver);

src/test/java/BlockChainTest.java

@@ -0,0 +1,84 @@
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import exceptions.NoSelfTransactionException;
+import exceptions.NotEnoughCoinsException;
+import java.io.IOException;
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
+import java.security.SignatureException;
+import java.security.spec.InvalidKeySpecException;
+import java.util.List;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+import model.BlockChain;
+import model.Miner;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+class BlockChainTest {
+
+  private final int nThreads = Runtime.getRuntime().availableProcessors();
+  private List<Miner> miners;
+  private BlockChain blockChain;
+
+  @BeforeEach
+  public void setUp() {
+    blockChain = new BlockChain();
+    blockChain.acceptUser("tester1", 100);
+    blockChain.acceptUser("tester2", 100);
+    miners = IntStream.range(0, 5)
+        .mapToObj(minerId -> new Miner(minerId, blockChain))
+        .collect(Collectors.toList());
+  }
+
+  @Test
+  void block_chain_correct_test()
+      throws InterruptedException, NoSuchAlgorithmException, SignatureException, IOException, InvalidKeySpecException, InvalidKeyException {
+
+    final var minerExecutor = Executors.newFixedThreadPool(nThreads);
+
+    for (final Miner miner: miners){
+      blockChain.acceptTransaction(blockChain.getNextTransactionId(), "tester1", 10, "tester2");
+      blockChain.acceptTransaction(blockChain.getNextTransactionId(), "tester2", 10, "tester1");
+      minerExecutor.execute(miner);
+    }
+
+    minerExecutor.shutdown();
+
+    if (!minerExecutor.awaitTermination(10, TimeUnit.SECONDS)) {
+      minerExecutor.shutdownNow();
+    }
+
+    assertTrue(blockChain.validateBlockchain());
+  }
+
+  @Test
+  void block_chain_not_enough_coins_test() {
+    final NotEnoughCoinsException thrown = assertThrows(
+        NotEnoughCoinsException.class,
+        () -> blockChain.acceptTransaction(
+            1,
+            "tester1",
+            110,
+            "tester2")
+    );
+    assertTrue(thrown.getMessage().contains("tester1 has not enough coins to perform the transaction"));
+  }
+
+  @Test
+  void block_chain_not_self_transaction_test() {
+    final NoSelfTransactionException thrown = assertThrows(
+        NoSelfTransactionException.class,
+        () -> blockChain.acceptTransaction(
+            1,
+            "tester1",
+            10,
+            "tester1")
+    );
+    assertTrue(thrown.getMessage().contains("tried to send coins to oneself"));
+  }
+
+}