The source of all technical debt

Indebted code is any code that is hard to scan. Technical debt is anything that increases the difficulty of reading code. As software engineers we spend most of the time reading code, and our job is to understand it and modify it in order to do more things with it. If we can’t understand the code, or we can’t even find it, the amount of technical debt accumulated will be over the roof.

Transcript

1. The source of all
   technical debt
   

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2. Indebted code is any code
   that is hard to scan.
   Technical debt is anything that
   increases the difficulty
   of reading code.
   

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3. Programmers spend around
   60-70%
   of their entire programming
   time reading code.
   Completely made up number based on my last month
   

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4. Cyclomatic complexity
   Software metric (measurement),
   used to indicate the complexity of a program.
   It is a quantitative measure of the number of
   linearly independent paths through
   a program's source code.
   

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5. Reducing technical debt
   Look at
   something
   Have an
   insight
   Write it down
   Check it in
   

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6. Reducing technical debt
   Have an
   insight
   

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7. Reducing technical debt
   Decide where
   to look
   Reading
   things,
   usually names
   In a name or
   assertion
   Name your
   commit
   

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8. 7 stages of naming
   

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9. Nonsense
   preloadDetails();
   

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10. Honest
    doSomethingEvilToTheDatabaseAndDisplayTheResult();
    

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11. Not just for functions
    public class DataManager
    public class DataProvider
    public class DataRepository
    public class DataOperations
    

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12. Honest and Complete
    parseXmlAndStoreFlightToDatabaseAndLocalCacheAndBeginBackgroundProcessing();
    

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14. Does the right thing
    storeFlightToDatabaseAndStartProcessing();
    

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15. Intent
    beginTrackingFlight();
    

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16. Domain abstraction
    MonitoringPanel.add(new Flight());
    

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17. Define your language
    

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18. De!ne your language
    presenter.loadFolders();
    presenter.getFolders();
    presenter.fetchFolders();
    view.presentFolders();
    view.showFolders();
    view.renderFolders();
    

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19. De!ne your language
    

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20. De!ne your language
    view.showFolders(boolean isOnline);
    presenter.loadFolders(boolean fromCache);
    

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21. De!ne your language
    presenter.loadFolders(boolean fromCache);
    view.showFolders();
    view.notifyOffline();
    

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22. Name by what it does, not by what it is
    @BindView(R.id.password_text_input_layout)
    TextInputLayout passwordTextInputLayout;
    @BindView(R.id.password_edit_text)
    EditText etPassword;
    @BindView(R.id.password)
    EditText passwordInput;
    

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23. Just say mNo to
    Hungarian Notation
    http://jakewharton.com/just-say-no-to-hungarian-notation/
    

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24. Say mNo to hungarian notation
    

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25. Your strict naming
    conventions are a
    liability
    https://publicobject.com/2016/01/20/strict-naming-conventions-are-a-liability/
    

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26. Rest API don’t de!ne your language
    {
    "files": {
    "Hello.txt": {
    "type": "text/plain",
    "content": "Hello World!\n"
    }
    },
    "created_at": "2014-05-27T02:31:35Z",
    "updated_at": "2015-08-29T14:01:51Z"
    }
    

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27. Rest API don’t de!ne your language
    public final class Gist {
    Map files;
    @SerializedName("created_at") Date createdAt;
    @SerializedName("updated_at") Date updatedAt;
    }
    

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28. Let’s talk about
    testing
    

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29. Naming your tests
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    DraftDialogPresenter.java
    

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30. Naming your tests
    DraftDialogPresenter.java
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    

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31. Naming your tests
    @Test
    public void draftDialogShowsMessageAfterClickingSaveButtonAndReloadsData()
    DraftDialogPresenter.java
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    

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32. Naming your tests
    DraftDialogPresenter.java
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void draftDialogShowsMessageAfterClickingSaveButtonAndReloadsData()
    

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33. Naming your tests
    DraftDialogPresenter.java
    @Test
    public void showsMessageWhenDraftIsSavedAndReloadsData()
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void draftDialogShowsMessageAfterClickingSaveButtonAndReloadsData()
    

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34. Naming your tests
    DraftDialogPresenter.java
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void draftDialogShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSavedAndReloadsData()
    

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35. Naming your tests
    DraftDialogPresenter.java
    @Test
    public void showsMessageWhenDraftIsSaved()
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void draftDialogShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSavedAndReloadsData()
    

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36. Naming your tests
    DraftDialogPresenter.java
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void draftDialogShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSavedAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSaved()
    

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37. Naming your tests
    DraftDialogPresenter.java
    @Test
    public void showsSuccessMessageWhenDraftIsSaved()
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void draftDialogShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSavedAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSaved()
    

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38. Naming your tests
    DraftDialogPresenter.java
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void draftDialogShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSavedAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSaved()
    @Test
    public void showsSuccessMessageWhenDraftIsSaved()
    

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39. Naming your tests
    DraftDialogPresenter.java
    @Test
    public void showsErrorMessageWhenDraftIsNotSaved()
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void draftDialogShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSavedAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSaved()
    @Test
    public void showsSuccessMessageWhenDraftIsSaved()
    

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40. Naming your tests
    DraftDialogPresenter.java
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void draftDialogShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSavedAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSaved()
    @Test
    public void showsSuccessMessageWhenDraftIsSaved()
    @Test
    public void showsErrorMessageWhenDraftIsNotSaved()
    

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41. Naming your tests
    DraftDialogPresenter.java
    @Test
    public void shows_error_mesage_when_draft_is_not_saved()
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void draftDialogShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSavedAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSaved()
    @Test
    public void showsSuccessMessageWhenDraftIsSaved()
    @Test
    public void showsErrorMessageWhenDraftIsNotSaved()
    

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42. Naming your tests
    DraftDialogPresenter.java
    @Test
    public void
    testDraftDialogPresenterShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void draftDialogShowsMessageAfterClickingSaveButtonAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSavedAndReloadsData()
    @Test
    public void showsMessageWhenDraftIsSaved()
    @Test
    public void showsSuccessMessageWhenDraftIsSaved()
    @Test
    public void showsErrorMessageWhenDraftIsNotSaved()
    @Test
    public void shows_error_mesage_when_draft_is_not_saved()
    

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43. Naming your tests
    DraftDialogPresenter.java
    // Groovy
    def "Should show success message after successfully saved a draft"()
    // Kotlin
    fun `Should show success message after successfully saved a draft`()
    

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44. Naming your tests
    @Test
    public void showsErrorMessageWhenDraftIsNotSaved()
    {}
    @Test
    public void
    shows_error_mesage_when_draft_is_not_saved() {}
    // Groovy
    def "Should show success message after
    successfully saved a draft"()
    // Kotlin
    fun `Should show success message after
    successfully saved a draft`()
    

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45. Android package
    structure
    

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47. helpscout
    api
    app
    database
    

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48. app
    common
    data
    domain
    injection
    

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49. domain
    conversations
    folders
    mailboxes
    session
    search
    settings
    

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50. mailboxes
    model
    usecases
    view
    MailboxesMVP
    MailboxesPresenter
    

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51. Android resource
    management
    

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52. Styles
    

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53. Styles
    android:id="@+id/conversations_list_subject_name"
    style="@style/Widget.Subject.Pending"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    tools:text="Customer Name" />
    view-convo-preview.xml
    

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54. Styles
    <br/><item name="android:textSize">@dimen/convo_subject_text</item><br/><item name="android:ellipsize">end</item><br/><item name="android:maxLines">1</item><br/>
    <br/><item name="android:textColor">@color/convo_preview_pending</item><br/>
    convo-preview-styles.xml
    

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55. Colors
    <br/><item name="android:textColor">@color/convo_preview_pending</item><br/>
    convo-preview-styles.xml
    @color/charcoal_300
    convo-preview-colors.xml
    #72808e
    colors.xml
    

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56. Dimensions
    <br/><item name="android:textSize">@dimen/convo_preview_text</item><br/><item name="android:ellipsize">end</item><br/><item name="android:maxLines">1</item><br/> convo-preview-styles.xml
    @dimen/text_subhead
    convo-preview-dimens.xml
    11sp
    dimens.xml
    

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57. Strings
    
    
    @string/convo_archived
    @string/convo_restored
    
    convo-preview-strings.xml
    Conversation archived.
    Conversation status restored.
    strings-translatable.xml
    

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59. Files
    

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60. We are talking about
    conventions
    and we should share them with the team
    

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61. https://google.github.io/styleguide/javaguide.html#s5.1-identifier-names
    

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62. http://s.android.com/source/code-style.html#follow-field-naming-conventions
    

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65. Enforce those
    conventions
    

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66. Enforce conventions
    

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67. Enforce conventions
    
    ...
    
    ...
    
    
    
    
    
    ...
    
    

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68. Enforce conventions
    
    
    
    
    
    
    
    value="Variable ''{0}'' should be in ALL_CAPS (if it is a constant) or be private
    (otherwise)." />
    
    
    team-props/checkstyle/modules.xml
    
    
    
    
    
    

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69. Enforce conventions
    
    
    
    
    
    
    
    
    
    
    
    
    team-props/pmd/ruleset.xml
    

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70. Enforce conventions
    static-analysis.gradle
    apply plugin: 'checkstyle'
    def rulesDir = new File(project.teamPropsDir, 'rules')
    task checkstyleMain(type: Checkstyle) {
    description 'Checks whether Java source code complies with coding rules.'
    ...
    }
    staticAnalysis.dependsOn checkstyleMain
    task verifyNoCheckstyleWarnings {
    doLast {
    File warningsFile = file('buildMessage/reports/checkstyle/main.xml')
    if (warningsFile.exists() && warningsFile.text.contains("throw new GradleException("There were checkstyle warnings!
    For more info check $warningsFile")
    }
    }
    }
    

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71. Enforce conventions
    static-analysis.gradle
    apply plugin: 'findbugs'
    task findbugsMain(type: FindBugs) {
    description 'Uses static analysis to look for bugs in Java code.'
    ...
    }
    staticAnalysis.dependsOn findbugsMain
    apply plugin: 'pmd'
    task pmdMain(type: Pmd) {
    description 'Finds common programming flaws throw static analysis of code.'
    }
    staticAnalysis.dependsOn pmdMain
    check.dependsOn staticAnalysis
    

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72. Static analysis
    

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73. Good naming is a process, not a single step
    - http://arlobelshee.com/good-naming-is-a-process-not-a-single-step/
    1
    Resources
    Just say hNo to hungarian notation
    - http://jakewharton.com/just-say-no-to-hungarian-notation/
    How We Rethought our Complete Package Structure for Buffer on Android and
    the Awesome Effect It’s Had on Our Workflows
    - https://overflow.buffer.com/2016/09/26/android-rethinking-package-structure/
    Share the settings with the whole team
    - https://tips.seebrock3r.me/share-settings-with-the-team-a-year-later-
    e28c24fc07aa#.sihndb3f3
    

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74. Novoda IDE Settings
    - https://github.com/novoda/novoda/tree/master/ide-settings
    1
    Resources
    Buffer’s Android Guidelines
    - https://github.com/bufferapp/android-guidelines
    Vincent Brison’s Static Analysis with Gradle
    - https://github.com/vincentbrison/vb-android-app-quality
    

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75. Questions?
    David González
    @dggonzalez
    malmstein@gmail.com
    

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