refactoring : duplicated code - extract function

refactoring/src/main/java/com/example/refactoring/_02_duplicated_code/_00_before/StudyDashboard.java

@@ -0,0 +1,48 @@
+package com.example.refactoring._02_duplicated_code._00_before;
+
+import org.kohsuke.github.GHIssue;
+import org.kohsuke.github.GHRepository;
+import org.kohsuke.github.GitHub;
+
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Set;
+
+public class StudyDashboard {
+
+    private void printParticipants(int eventId) throws IOException {
+        // Get github issue to check homework
+        GitHub gitHub = GitHub.connect();
+        GHRepository repository = gitHub.getRepository("haerong22/Study");
+        GHIssue issue = repository.getIssue(eventId);
+
+        // Get participants
+        Set<String> participants = new HashSet<>();
+        issue.getComments().forEach(c -> participants.add(c.getUserName()));
+
+        // Print participants
+        participants.forEach(System.out::println);
+    }
+
+    private void printReviewers() throws IOException {
+        // Get github issue to check homework
+        GitHub gitHub = GitHub.connect();
+        GHRepository repository = gitHub.getRepository("haerong22/Study");
+        GHIssue issue = repository.getIssue(1);
+
+        // Get reviewers
+        Set<String> reviewers = new HashSet<>();
+        issue.getComments().forEach(c -> reviewers.add(c.getUserName()));
+
+        // Print reviewers
+        reviewers.forEach(System.out::println);
+    }
+
+    public static void main(String[] args) throws IOException {
+        StudyDashboard studyDashboard = new StudyDashboard();
+        studyDashboard.printReviewers();
+        studyDashboard.printParticipants(1);
+
+    }
+
+}

refactoring/src/main/java/com/example/refactoring/_02_duplicated_code/_04_extract_function/StudyDashboard.java

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+package com.example.refactoring._02_duplicated_code._04_extract_function;
+
+import org.kohsuke.github.GHIssue;
+import org.kohsuke.github.GHRepository;
+import org.kohsuke.github.GitHub;
+
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Set;
+
+public class StudyDashboard {
+
+    private void printParticipants(int eventId) throws IOException {
+        // 메소드를 추출하여 해당 코드의 의도를 명확하게 전달 할 수 있다.(구현은 메소드에서)
+        GHIssue issue = getGhIssue(eventId);
+        Set<String> participants = getUsernames(issue);
+        print(participants);
+    }
+
+    private void print(Set<String> participants) {
+        participants.forEach(System.out::println);
+    }
+
+    private Set<String> getUsernames(GHIssue issue) throws IOException {
+        Set<String> usernames = new HashSet<>();
+        issue.getComments().forEach(c -> usernames.add(c.getUserName()));
+        return usernames;
+    }
+
+    private GHIssue getGhIssue(int eventId) throws IOException {
+        GitHub gitHub = GitHub.connect();
+        GHRepository repository = gitHub.getRepository("haerong22/Study");
+        GHIssue issue = repository.getIssue(eventId);
+        return issue;
+    }
+
+    private void printReviewers() throws IOException {
+        GHIssue issue = getGhIssue(1);
+        Set<String> reviewers = getUsernames(issue);
+        print(reviewers);
+    }
+
+    public static void main(String[] args) throws IOException {
+        StudyDashboard studyDashboard = new StudyDashboard();
+        studyDashboard.printReviewers();
+        studyDashboard.printParticipants(1);
+
+    }
+}