Computing changeCountsByTimeStamps only once

Author: jimbethancourt

change-proneness-ranker/src/main/java/org/hjug/git/ChangePronenessRanker.java

@@ -11,24 +11,18 @@
 @Slf4j
 public class ChangePronenessRanker {
 
-    private Repository repository;
-    private GitLogReader repositoryLogReader;
+    private final TreeMap<Integer, Integer> changeCountsByTimeStamps = new TreeMap<>();
 
     public ChangePronenessRanker(Repository repository, GitLogReader repositoryLogReader) {
-        this.repositoryLogReader = repositoryLogReader;
-        this.repository = repository;
-    }
-
-    public void rankChangeProneness(List<ScmLogInfo> scmLogInfos) {
-        TreeMap<Integer, Integer> changeCountsByTimeStamps = new TreeMap<>();
-
         try {
             log.info("Capturing change count based on commit timestamps");
             changeCountsByTimeStamps.putAll(repositoryLogReader.captureChangeCountByCommitTimestamp(repository));
         } catch (IOException | GitAPIException e) {
             log.error("Error reading from repository: {}", e.getMessage());
         }
+    }
 
+    public void rankChangeProneness(List<ScmLogInfo> scmLogInfos) {
         for (ScmLogInfo scmLogInfo : scmLogInfos) {
             int commitsInRepositorySinceCreation =
                     changeCountsByTimeStamps.tailMap(scmLogInfo.getEarliestCommit()).values().stream()

change-proneness-ranker/src/test/java/org/hjug/git/ChangePronenessRankerTest.java

@@ -11,15 +11,14 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-public class ChangePronenessRankerTest {
+class ChangePronenessRankerTest {
 
     private ChangePronenessRanker changePronenessRanker;
     private GitLogReader repositoryLogReader;
 
     @BeforeEach
     public void setUp() {
         repositoryLogReader = mock(GitLogReader.class);
-        changePronenessRanker = new ChangePronenessRanker(null, repositoryLogReader);
     }
 
     // TODO: this should probably be a cucumber test
@@ -34,6 +33,7 @@ void testChangePronenessCalculation() throws IOException, GitAPIException {
 
         when(repositoryLogReader.captureChangeCountByCommitTimestamp(any())).thenReturn(commitsWithChangeCounts);
 
+        changePronenessRanker = new ChangePronenessRanker(null, repositoryLogReader);
         List<ScmLogInfo> scmLogInfos = new ArrayList<>();
         scmLogInfos.add(scmLogInfo);
         changePronenessRanker.rankChangeProneness(scmLogInfos);
@@ -58,6 +58,7 @@ void testRankChangeProneness() throws IOException, GitAPIException {
         commitsWithChangeCounts.put(scmLogInfo2.getEarliestCommit() + 10 * 60, 5);
 
         when(repositoryLogReader.captureChangeCountByCommitTimestamp(any())).thenReturn(commitsWithChangeCounts);
+        changePronenessRanker = new ChangePronenessRanker(null, repositoryLogReader);
 
         List<ScmLogInfo> scmLogInfos = new ArrayList<>();
         scmLogInfos.add(scmLogInfo);