Fix based on feedback

Author: brfrn169

core/src/main/java/com/scalar/db/transaction/consensuscommit/ConsensusCommitScanner.java

@@ -0,0 +1,7 @@
+package com.scalar.db.transaction.consensuscommit;
+
+import com.scalar.db.api.TransactionCrudOperable;
+
+public interface ConsensusCommitScanner extends TransactionCrudOperable.Scanner {
+  boolean isClosed();
+}

core/src/main/java/com/scalar/db/transaction/consensuscommit/CrudHandler.java

@@ -736,10 +736,6 @@ private TableMetadata getTableMetadata(Operation operation, String transactionId
     return metadata.getTableMetadata();
   }
 
-  public interface ConsensusCommitScanner extends TransactionCrudOperable.Scanner {
-    boolean isClosed();
-  }
-
   @NotThreadSafe
   private class ConsensusCommitStorageScanner extends AbstractTransactionCrudOperableScanner
       implements ConsensusCommitScanner {

core/src/main/java/com/scalar/db/transaction/consensuscommit/TransactionContext.java

@@ -24,7 +24,7 @@ public class TransactionContext {
   public final boolean oneOperation;
 
   // A list of scanners opened in the transaction
-  public final List<CrudHandler.ConsensusCommitScanner> scanners = new ArrayList<>();
+  public final List<ConsensusCommitScanner> scanners = new ArrayList<>();
 
   // A list of recovery results performed in the transaction
   public final List<RecoveryExecutor.Result> recoveryResults = new ArrayList<>();
@@ -51,11 +51,11 @@ public boolean isValidationRequired() {
   }
 
   public boolean areAllScannersClosed() {
-    return scanners.stream().allMatch(CrudHandler.ConsensusCommitScanner::isClosed);
+    return scanners.stream().allMatch(ConsensusCommitScanner::isClosed);
   }
 
   public void closeScanners() throws CrudException {
-    for (CrudHandler.ConsensusCommitScanner scanner : scanners) {
+    for (ConsensusCommitScanner scanner : scanners) {
       if (!scanner.isClosed()) {
         scanner.close();
       }

core/src/test/java/com/scalar/db/transaction/consensuscommit/ConsensusCommitManagerTest.java

@@ -187,6 +187,22 @@ public void begin_TxIdGiven_ReturnWithSpecifiedTxIdAndSnapshotIsolation() {
     verify(groupCommitter, never()).reserve(ANY_TX_ID);
   }
 
+  @Test
+  public void begin_CalledTwice_ShouldReturnTransactionsWithSharedHandlers() {
+    // Arrange
+
+    // Act
+    ConsensusCommit transaction1 = (ConsensusCommit) manager.begin();
+    ConsensusCommit transaction2 = (ConsensusCommit) manager.begin();
+
+    // Assert
+    assertThat(transaction1.getCrudHandler()).isSameAs(transaction2.getCrudHandler());
+    assertThat(transaction1.getCommitHandler()).isSameAs(transaction2.getCommitHandler());
+    assertThat(transaction1.getTransactionContext())
+        .isNotSameAs(transaction2.getTransactionContext());
+    assertThat(transaction1.getId()).isNotEqualTo(transaction2.getId());
+  }
+
   @Test
   public void begin_CalledTwiceWithSameTxId_ThrowTransactionException()
       throws TransactionException {
@@ -285,6 +301,23 @@ public void start_NullIsolationGiven_ThrowNullPointerExceptionException() {
         .isInstanceOf(NullPointerException.class);
   }
 
+  @Test
+  public void start_CalledTwice_ShouldReturnTransactionsWithSharedHandlers()
+      throws TransactionException {
+    // Arrange
+
+    // Act
+    ConsensusCommit transaction1 = (ConsensusCommit) manager.start();
+    ConsensusCommit transaction2 = (ConsensusCommit) manager.start();
+
+    // Assert
+    assertThat(transaction1.getCrudHandler()).isSameAs(transaction2.getCrudHandler());
+    assertThat(transaction1.getCommitHandler()).isSameAs(transaction2.getCommitHandler());
+    assertThat(transaction1.getTransactionContext())
+        .isNotSameAs(transaction2.getTransactionContext());
+    assertThat(transaction1.getId()).isNotEqualTo(transaction2.getId());
+  }
+
   @Test
   public void start_CalledTwiceWithSameTxId_ThrowTransactionException()
       throws TransactionException {

core/src/test/java/com/scalar/db/transaction/consensuscommit/TwoPhaseConsensusCommitManagerTest.java

@@ -118,6 +118,22 @@ public void begin_TxIdGiven_ReturnWithSpecifiedTxIdAndSnapshotIsolation() {
     assertThat(transaction.getCommitHandler()).isEqualTo(commit);
   }
 
+  @Test
+  public void begin_CalledTwice_ShouldReturnTransactionsWithSharedHandlers() {
+    // Arrange
+
+    // Act
+    TwoPhaseConsensusCommit transaction1 = (TwoPhaseConsensusCommit) manager.begin();
+    TwoPhaseConsensusCommit transaction2 = (TwoPhaseConsensusCommit) manager.begin();
+
+    // Assert
+    assertThat(transaction1.getCrudHandler()).isSameAs(transaction2.getCrudHandler());
+    assertThat(transaction1.getCommitHandler()).isSameAs(transaction2.getCommitHandler());
+    assertThat(transaction1.getTransactionContext())
+        .isNotSameAs(transaction2.getTransactionContext());
+    assertThat(transaction1.getId()).isNotEqualTo(transaction2.getId());
+  }
+
   @Test
   public void begin_CalledTwiceWithSameTxId_ThrowTransactionException()
       throws TransactionException {
@@ -180,6 +196,23 @@ public void start_TxIdGiven_ReturnWithSpecifiedTxIdAndSnapshotIsolation()
     assertThat(transaction.getCommitHandler()).isEqualTo(commit);
   }
 
+  @Test
+  public void start_CalledTwice_ShouldReturnTransactionsWithSharedHandlers()
+      throws TransactionException {
+    // Arrange
+
+    // Act
+    TwoPhaseConsensusCommit transaction1 = (TwoPhaseConsensusCommit) manager.start();
+    TwoPhaseConsensusCommit transaction2 = (TwoPhaseConsensusCommit) manager.start();
+
+    // Assert
+    assertThat(transaction1.getCrudHandler()).isSameAs(transaction2.getCrudHandler());
+    assertThat(transaction1.getCommitHandler()).isSameAs(transaction2.getCommitHandler());
+    assertThat(transaction1.getTransactionContext())
+        .isNotSameAs(transaction2.getTransactionContext());
+    assertThat(transaction1.getId()).isNotEqualTo(transaction2.getId());
+  }
+
   @Test
   public void start_CalledTwiceWithSameTxId_ThrowTransactionException()
       throws TransactionException {