There is 1 Broken API Among Us

As a library user, you probably know that versions don't always tell the truth. Have you ever experienced a broken build after doing a minor bump of a library?

As a library author, maintaining a clean API is a challenge. There is always the risk that a breaking change sneaks in by accident.

Wouldn't it be nice to get notified if you're accidentally breaking your users' code? A tool to inspect the binary API of your Kotlin/Java code can help you exactly with that. In this talk, we will see some of those tools and how that simplifies the life of library & SDK developers.

Transcript

1. THERE IS 1 BROKEN API AMONG US
   @CORTINICO
   

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2. NICOLA CORTI
   Kotlin GDE
   Android Infra Eng. @ Spotify
   twitter.com/cortinico
   github.com/cortinico
   ncorti.com
   

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3. WHO IS THIS TALK FOR?
   

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4. WHO IS THIS TALK FOR?
   • Library Devs
   • SDK Devs
   • Open Source Devs
   • Mobile Devs in a Modularized world
   

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5. GOOD API CITIZENS
   

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6. GOOD API CITIZENS @Deprecate
   

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7. GOOD API CITIZENS @Deprecate
   fun replace(with: String)
   

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8. GOOD API CITIZENS @Deprecate
   @Deprecated
   fun replace(with: String)
   

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9. GOOD API CITIZENS @Deprecate
   @Deprecated(
   message = "This method is affected by a bug"
   )
   fun replace(with: String)
   

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10. GOOD API CITIZENS @Deprecate
    @Deprecated(
    message = "This method is affected by a bug",
    replaceWith = ReplaceWith("newReplace(with)")
    )
    fun replace(with: String)
    

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11. GOOD API CITIZENS @Deprecate
    @Deprecated(
    message = "This method is affected by a bug",
    replaceWith = ReplaceWith("newReplace(with)"),
    level = DeprecationLevel.ERROR
    )
    fun replace(with: String)
    

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12. GOOD API CITIZENS @OptIn
    

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13. GOOD API CITIZENS @OptIn
    fun getAnswer() = 42
    

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14. GOOD API CITIZENS @OptIn
    @MyExperimentalApi
    fun getAnswer() = 42
    

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15. GOOD API CITIZENS @OptIn
    @RequiresOptIn(message = "This API is experimental")
    annotation class MyExperimentalApi
    @MyExperimentalApi
    fun getAnswer() = 42
    

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16. GOOD API CITIZENS @OptIn
    @RequiresOptIn(message = "This API is experimental")
    annotation class MyExperimentalApi
    @MyExperimentalApi
    fun getAnswer() = 42
    fun main() {
    println(getAnswer())
    }
    

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17. GOOD API CITIZENS @OptIn
    @RequiresOptIn(message = "This API is experimental")
    annotation class MyExperimentalApi
    @MyExperimentalApi
    fun getAnswer() = 42
    @MyExperimentalApi
    fun main() {
    println(getAnswer())
    }
    

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18. GOOD API CITIZENS @OptIn
    @RequiresOptIn(message = "This API is experimental")
    annotation class MyExperimentalApi
    @MyExperimentalApi
    fun getAnswer() = 42
    @OptIn(MyExperimentalApi::class)
    fun main() {
    println(getAnswer())
    }
    

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19. GOOD API CITIZENS Explicit API Mode
    kotlin {
    explicitApiWarning()
    }
    

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20. GOOD API CITIZENS Explicit API Mode
    kotlin {
    explicitApi()
    }
    

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21. GOOD API CITIZENS Explicit API Mode
    kotlin {
    explicitApi()
    }
    fun getAnswer() = 42
    

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22. GOOD API CITIZENS Explicit API Mode
    kotlin {
    explicitApi()
    }
    fun getAnswer() = 42.0
    

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23. GOOD API CITIZENS Explicit API Mode
    kotlin {
    explicitApi()
    }
    public fun getAnswer() : Int = 42
    

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24. GOOD API CITIZENS @SemVer
    

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25. GOOD API CITIZENS @SemVer
    MAJOR.
    

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26. GOOD API CITIZENS @SemVer
    MAJOR.MINOR.
    

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27. GOOD API CITIZENS @SemVer
    MAJOR.MINOR.PATCH
    

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28. GOOD API CITIZENS @SemVer
    MAJOR.MINOR.PATCH
    

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29. GOOD API CITIZENS @SemVer
    MAJOR.MINOR.PATCH
    

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30. GOOD API CITIZENS @SemVer
    MAJOR.MINOR.PATCH
    

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31. BINARY COMPATIBILITY VALIDATOR
    

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32. BINARY COMPATIBILITY VALIDATOR
    

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33. BINARY COMPATIBILITY VALIDATOR
    

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34. BINARY COMPATIBILITY VALIDATOR Setup
    

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35. BINARY COMPATIBILITY VALIDATOR
    buildscript {
    dependencies {
    classpath("org.jetbrains.kotlinx:binary-compatibility-validator:0.2.4")
    }
    }
    apply plugin: "binary-compatibility-validator"
    Setup
    

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36. BINARY COMPATIBILITY VALIDATOR
    buildscript {
    dependencies {
    classpath("org.jetbrains.kotlinx:binary-compatibility-validator:0.2.4")
    }
    }
    apply plugin: "binary-compatibility-validator"
    Setup
    apiValidation {
    }
    

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37. BINARY COMPATIBILITY VALIDATOR
    buildscript {
    dependencies {
    classpath("org.jetbrains.kotlinx:binary-compatibility-validator:0.2.4")
    }
    }
    apply plugin: "binary-compatibility-validator"
    Setup
    apiValidation {
    ignoredProjects += ["sample"]
    }
    

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38. BINARY COMPATIBILITY VALIDATOR
    buildscript {
    dependencies {
    classpath("org.jetbrains.kotlinx:binary-compatibility-validator:0.2.4")
    }
    }
    apply plugin: "binary-compatibility-validator"
    Setup
    apiValidation {
    ignoredProjects += ["sample"]
    ignoredPackages += ["com.chuckerteam.chucker.internal"]
    }
    

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39. BINARY COMPATIBILITY VALIDATOR
    buildscript {
    dependencies {
    classpath("org.jetbrains.kotlinx:binary-compatibility-validator:0.2.4")
    }
    }
    apply plugin: "binary-compatibility-validator"
    Setup
    apiValidation {
    ignoredProjects += ["sample"]
    ignoredPackages += ["com.chuckerteam.chucker.internal"]
    nonPublicMarkers += ["com.chuckerteam.chucker.InternalApiAnnotation"]
    }
    

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40. BINARY COMPATIBILITY VALIDATOR
    buildscript {
    dependencies {
    classpath("org.jetbrains.kotlinx:binary-compatibility-validator:0.2.4")
    }
    }
    apply plugin: "binary-compatibility-validator"
    Setup
    apiValidation {
    ignoredProjects += ["sample"]
    ignoredPackages += ["com.chuckerteam.chucker.internal"]
    nonPublicMarkers += ["com.chuckerteam.chucker.InternalApiAnnotation"]
    }
    $ ./gradlew apiDump
    

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41. BINARY COMPATIBILITY VALIDATOR .api File
    

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42. BINARY COMPATIBILITY VALIDATOR .api File
    public final class com/chuckerteam/chucker/BuildConfig {
    public static final field BUILD_TYPE Ljava/lang/String;
    public static final field DEBUG Z
    public static final field LIBRARY_PACKAGE_NAME Ljava/lang/String;
    public fun ()V
    }
    public final class com/chuckerteam/chucker/api/Chucker {
    public static final field INSTANCE Lcom/chuckerteam/chucker/api/Chucker;
    public static final fun dismissNotifications (Landroid/content/Context;)V
    public static final fun getLaunchIntent (Landroid/content/Context;)Landroid/content/Intent;
    public final fun isOp ()Z
    }
    public final class com/chuckerteam/chucker/api/ChuckerCollector {
    public fun (Landroid/content/Context;)V
    public fun (Landroid/content/Context;Z)V
    public fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/RetentionManager$Period;)V
    public synthetic fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/
    RetentionManager$Period;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
    public final fun getShowNotification ()Z
    public final fun setShowNotification (Z)V
    }
    public final class com/chuckerteam/chucker/api/ChuckerInterceptor : okhttp3/Interceptor {
    

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43. BINARY COMPATIBILITY VALIDATOR .api File
    public final class com/chuckerteam/chucker/BuildConfig {
    public static final field BUILD_TYPE Ljava/lang/String;
    public static final field DEBUG Z
    public static final field LIBRARY_PACKAGE_NAME Ljava/lang/String;
    public fun ()V
    }
    public final class com/chuckerteam/chucker/api/Chucker {
    public static final field INSTANCE Lcom/chuckerteam/chucker/api/Chucker;
    public static final fun dismissNotifications (Landroid/content/Context;)V
    public static final fun getLaunchIntent (Landroid/content/Context;)Landroid/content/Intent;
    public final fun isOp ()Z
    }
    public final class com/chuckerteam/chucker/api/ChuckerCollector {
    public fun (Landroid/content/Context;)V
    public fun (Landroid/content/Context;Z)V
    public fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/RetentionManager$Period;)V
    public synthetic fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/
    RetentionManager$Period;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
    public final fun getShowNotification ()Z
    public final fun setShowNotification (Z)V
    }
    public final class com/chuckerteam/chucker/api/ChuckerInterceptor : okhttp3/Interceptor {
    

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44. BINARY COMPATIBILITY VALIDATOR .api File
    public final class com/chuckerteam/chucker/BuildConfig {
    public static final field BUILD_TYPE Ljava/lang/String;
    public static final field DEBUG Z
    public static final field LIBRARY_PACKAGE_NAME Ljava/lang/String;
    public fun ()V
    }
    public final class com/chuckerteam/chucker/api/Chucker {
    public static final field INSTANCE Lcom/chuckerteam/chucker/api/Chucker;
    public static final fun dismissNotifications (Landroid/content/Context;)V
    public static final fun getLaunchIntent (Landroid/content/Context;)Landroid/content/Intent;
    public final fun isOp ()Z
    }
    public final class com/chuckerteam/chucker/api/ChuckerCollector {
    public fun (Landroid/content/Context;)V
    public fun (Landroid/content/Context;Z)V
    public fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/RetentionManager$Period;)V
    public synthetic fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/
    RetentionManager$Period;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
    public final fun getShowNotification ()Z
    public final fun setShowNotification (Z)V
    }
    public final class com/chuckerteam/chucker/api/ChuckerInterceptor : okhttp3/Interceptor {
    

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45. BINARY COMPATIBILITY VALIDATOR .api File
    public final class com/chuckerteam/chucker/BuildConfig {
    public static final field BUILD_TYPE Ljava/lang/String;
    public static final field DEBUG Z
    public static final field LIBRARY_PACKAGE_NAME Ljava/lang/String;
    public fun ()V
    }
    public final class com/chuckerteam/chucker/api/Chucker {
    public static final field INSTANCE Lcom/chuckerteam/chucker/api/Chucker;
    public static final fun dismissNotifications (Landroid/content/Context;)V
    public static final fun getLaunchIntent (Landroid/content/Context;)Landroid/content/Intent;
    public final fun isOp ()Z
    }
    public final class com/chuckerteam/chucker/api/ChuckerCollector {
    public fun (Landroid/content/Context;)V
    public fun (Landroid/content/Context;Z)V
    public fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/RetentionManager$Period;)V
    public synthetic fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/
    RetentionManager$Period;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
    public final fun getShowNotification ()Z
    public final fun setShowNotification (Z)V
    }
    public final class com/chuckerteam/chucker/api/ChuckerInterceptor : okhttp3/Interceptor {
    

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46. BINARY COMPATIBILITY VALIDATOR .api File
    public final class com/chuckerteam/chucker/BuildConfig {
    public static final field BUILD_TYPE Ljava/lang/String;
    public static final field DEBUG Z
    public static final field LIBRARY_PACKAGE_NAME Ljava/lang/String;
    public fun ()V
    }
    public final class com/chuckerteam/chucker/api/Chucker {
    public static final field INSTANCE Lcom/chuckerteam/chucker/api/Chucker;
    public static final fun dismissNotifications (Landroid/content/Context;)V
    public static final fun getLaunchIntent (Landroid/content/Context;)Landroid/content/Intent;
    public final fun isOp ()Z
    }
    public final class com/chuckerteam/chucker/api/ChuckerCollector {
    public fun (Landroid/content/Context;)V
    public fun (Landroid/content/Context;Z)V
    public fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/RetentionManager$Period;)V
    public synthetic fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/
    RetentionManager$Period;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
    public final fun getShowNotification ()Z
    public final fun setShowNotification (Z)V
    }
    public final class com/chuckerteam/chucker/api/ChuckerInterceptor : okhttp3/Interceptor {
    

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47. BINARY COMPATIBILITY VALIDATOR .api File
    public final class com/chuckerteam/chucker/BuildConfig {
    public static final field BUILD_TYPE Ljava/lang/String;
    public static final field DEBUG Z
    public static final field LIBRARY_PACKAGE_NAME Ljava/lang/String;
    public fun ()V
    }
    public final class com/chuckerteam/chucker/api/Chucker {
    public static final field INSTANCE Lcom/chuckerteam/chucker/api/Chucker;
    public static final fun dismissNotifications (Landroid/content/Context;)V
    public static final fun getLaunchIntent (Landroid/content/Context;)Landroid/content/Intent;
    public final fun isOp ()Z
    }
    public final class com/chuckerteam/chucker/api/ChuckerCollector {
    public fun (Landroid/content/Context;)V
    public fun (Landroid/content/Context;Z)V
    public fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/RetentionManager$Period;)V
    public synthetic fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/
    RetentionManager$Period;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
    public final fun getShowNotification ()Z
    public final fun setShowNotification (Z)V
    }
    public final class com/chuckerteam/chucker/api/ChuckerInterceptor : okhttp3/Interceptor {
    

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48. BINARY COMPATIBILITY VALIDATOR .api File
    public final class com/chuckerteam/chucker/BuildConfig {
    public static final field BUILD_TYPE Ljava/lang/String;
    public static final field DEBUG Z
    public static final field LIBRARY_PACKAGE_NAME Ljava/lang/String;
    public fun ()V
    }
    public final class com/chuckerteam/chucker/api/Chucker {
    public static final field INSTANCE Lcom/chuckerteam/chucker/api/Chucker;
    public static final fun dismissNotifications (Landroid/content/Context;)V
    public static final fun getLaunchIntent (Landroid/content/Context;)Landroid/content/Intent;
    public final fun isOp ()Z
    }
    public final class com/chuckerteam/chucker/api/ChuckerCollector {
    public fun (Landroid/content/Context;)V
    public fun (Landroid/content/Context;Z)V
    public fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/RetentionManager$Period;)V
    public synthetic fun (Landroid/content/Context;ZLcom/chuckerteam/chucker/api/
    RetentionManager$Period;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
    public final fun getShowNotification ()Z
    public final fun setShowNotification (Z)V
    }
    public final class com/chuckerteam/chucker/api/ChuckerInterceptor : okhttp3/Interceptor {
    

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49. BINARY COMPATIBILITY VALIDATOR Normal Workflow
    $ ./gradlew apiCheck
    

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50. BINARY COMPATIBILITY VALIDATOR Normal Workflow
    $ ./gradlew apiCheck
    # OR
    $ ./gradlew check
    

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51. BINARY COMPATIBILITY VALIDATOR Normal Workflow
    $ ./gradlew apiCheck
    # OR
    $ ./gradlew check
    # Computed API has not changed
    BUILD SUCCESSFUL
    

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52. BINARY COMPATIBILITY VALIDATOR Normal Workflow
    $ ./gradlew apiCheck
    # OR
    $ ./gradlew check
    # Computed API has not changed
    BUILD SUCCESSFUL
    # Computed API has changed
    BUILD FAILED
    

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53. BINARY COMPATIBILITY VALIDATOR Non-Breaking
    

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54. BINARY COMPATIBILITY VALIDATOR Breaking
    

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55. JAPICMP
    

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56. JAPICMP
    

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57. JAPICMP
    

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58. JAPICMP
    search.maven.org/artifact/com.github.siom79.japicmp/japicmp
    Download
    

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59. JAPICMP CLI
    $ java -jar japicmp-0.14.4-jar-with-dependencies.jar -h
    SYNOPSIS
    java -jar japicmp.jar [-a ] [(-b | --only-incompatible)]
    [(-e | --exclude )] [--exclude-exclusively]
    [(-h | --help)] [--html-file ]
    [--html-stylesheet ]
    [(-i | --include )] [--ignore-missing-classes]
    [--ignore-missing-classes-by-regex ...]
    [--include-exclusively] [--include-synthetic] [(-m | --only-modified)]
    [(-n | --new )]
    [--new-classpath ] [--no-annotations]
    [(-o | --old )]
    [--old-classpath ] [--report-only-filename]
    [(-s | --semantic-versioning)]
    [(-x | --xml-file )]
    [--error-on-binary-incompatibility]
    [--error-on-source-incompatibility]
    [--error-on-modifications]
    [--no-error-on-exclusion-incompatibility]
    

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60. JAPICMP CLI
    $ java -jar japicmp-0.14.4-jar-with-dependencies.jar -h
    SYNOPSIS
    java -jar japicmp.jar [-a ] [(-b | --only-incompatible)]
    [(-e | --exclude )] [--exclude-exclusively]
    [(-h | --help)] [--html-file ]
    [--html-stylesheet ]
    [(-i | --include )] [--ignore-missing-classes]
    [--ignore-missing-classes-by-regex ...]
    [--include-exclusively] [--include-synthetic] [(-m | --only-modified)]
    [(-n | --new )]
    [--new-classpath ] [--no-annotations]
    [(-o | --old )]
    [--old-classpath ] [--report-only-filename]
    [(-s | --semantic-versioning)]
    [(-x | --xml-file )]
    [--error-on-binary-incompatibility]
    [--error-on-source-incompatibility]
    [--error-on-modifications]
    [--no-error-on-exclusion-incompatibility]
    

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61. JAPICMP CLI
    $ java -jar japicmp-0.14.4-jar-with-dependencies.jar -h
    SYNOPSIS
    java -jar japicmp.jar [-a ] [(-b | --only-incompatible)]
    [(-e | --exclude )] [--exclude-exclusively]
    [(-h | --help)] [--html-file ]
    [--html-stylesheet ]
    [(-i | --include )] [--ignore-missing-classes]
    [--ignore-missing-classes-by-regex ...]
    [--include-exclusively] [--include-synthetic] [(-m | --only-modified)]
    [(-n | --new )]
    [--new-classpath ] [--no-annotations]
    [(-o | --old )]
    [--old-classpath ] [--report-only-filename]
    [(-s | --semantic-versioning)]
    [(-x | --xml-file )]
    [--error-on-binary-incompatibility]
    [--error-on-source-incompatibility]
    [--error-on-modifications]
    [--no-error-on-exclusion-incompatibility]
    

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62. JAPICMP CLI
    $ java -jar japicmp-0.14.4-jar-with-dependencies.jar -h
    SYNOPSIS
    java -jar japicmp.jar [-a ] [(-b | --only-incompatible)]
    [(-e | --exclude )] [--exclude-exclusively]
    [(-h | --help)] [--html-file ]
    [--html-stylesheet ]
    [(-i | --include )] [--ignore-missing-classes]
    [--ignore-missing-classes-by-regex ...]
    [--include-exclusively] [--include-synthetic] [(-m | --only-modified)]
    [(-n | --new )]
    [--new-classpath ] [--no-annotations]
    [(-o | --old )]
    [--old-classpath ] [--report-only-filename]
    [(-s | --semantic-versioning)]
    [(-x | --xml-file )]
    [--error-on-binary-incompatibility]
    [--error-on-source-incompatibility]
    [--error-on-modifications]
    [--no-error-on-exclusion-incompatibility]
    

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63. JAPICMP CLI
    $ java -jar japicmp-0.14.4-jar-with-dependencies.jar -h
    SYNOPSIS
    java -jar japicmp.jar [-a ] [(-b | --only-incompatible)]
    [(-e | --exclude )] [--exclude-exclusively]
    [(-h | --help)] [--html-file ]
    [--html-stylesheet ]
    [(-i | --include )] [--ignore-missing-classes]
    [--ignore-missing-classes-by-regex ...]
    [--include-exclusively] [--include-synthetic] [(-m | --only-modified)]
    [(-n | --new )]
    [--new-classpath ] [--no-annotations]
    [(-o | --old )]
    [--old-classpath ] [--report-only-filename]
    [(-s | --semantic-versioning)]
    [(-x | --xml-file )]
    [--error-on-binary-incompatibility]
    [--error-on-source-incompatibility]
    [--error-on-modifications]
    [--no-error-on-exclusion-incompatibility]
    

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64. JAPICMP CLI
    $ java -jar japicmp-0.14.4-jar-with-dependencies.jar -h
    SYNOPSIS
    java -jar japicmp.jar [-a ] [(-b | --only-incompatible)]
    [(-e | --exclude )] [--exclude-exclusively]
    [(-h | --help)] [--html-file ]
    [--html-stylesheet ]
    [(-i | --include )] [--ignore-missing-classes]
    [--ignore-missing-classes-by-regex ...]
    [--include-exclusively] [--include-synthetic] [(-m | --only-modified)]
    [(-n | --new )]
    [--new-classpath ] [--no-annotations]
    [(-o | --old )]
    [--old-classpath ] [--report-only-filename]
    [(-s | --semantic-versioning)]
    [(-x | --xml-file )]
    [--error-on-binary-incompatibility]
    [--error-on-source-incompatibility]
    [--error-on-modifications]
    [--no-error-on-exclusion-incompatibility]
    [--error-on-semantic-incompatibility]
    

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65. JAPICMP CLI
    $ java -jar japicmp-0.14.4-jar-with-dependencies.jar -h
    SYNOPSIS
    java -jar japicmp.jar [-a ] [(-b | --only-incompatible)]
    [(-e | --exclude )] [--exclude-exclusively]
    [(-h | --help)] [--html-file ]
    [--html-stylesheet ]
    [(-i | --include )] [--ignore-missing-classes]
    [--ignore-missing-classes-by-regex ...]
    [--include-exclusively] [--include-synthetic] [(-m | --only-modified)]
    [(-n | --new )]
    [--new-classpath ] [--no-annotations]
    [(-o | --old )]
    [--old-classpath ] [--report-only-filename]
    [(-s | --semantic-versioning)]
    [(-x | --xml-file )]
    [--error-on-binary-incompatibility]
    [--error-on-source-incompatibility]
    [--error-on-modifications]
    [--no-error-on-exclusion-incompatibility]
    

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66. JAPICMP CLI
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    

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67. JAPICMP CLI
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    --old library-3.3.0/classes.jar \
    

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68. JAPICMP CLI
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    --old library-3.3.0/classes.jar \
    --new library-3.4.0/classes.jar \
    

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69. JAPICMP CLI
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    --old library-3.3.0/classes.jar \
    --new library-3.4.0/classes.jar \
    --html-file index.html \
    

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70. JAPICMP CLI
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    --old library-3.3.0/classes.jar \
    --new library-3.4.0/classes.jar \
    --html-file index.html \
    --include “com.chuckerteam.chucker.api” \
    --include-exclusively
    

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71. JAPICMP CLI
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    --old library-3.3.0/classes.jar \
    --new library-3.4.0/classes.jar \
    --html-file index.html \
    --include “com.chuckerteam.chucker.api” \
    --include-exclusively
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    --old library-3.3.0/classes.jar \
    --new library-3.4.0/classes.jar \
    --html-file index.html \
    

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72. JAPICMP CLI
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    --old library-3.3.0/classes.jar \
    --new library-3.4.0/classes.jar \
    --html-file index.html \
    --include “com.chuckerteam.chucker.api” \
    --include-exclusively
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    --old library-3.3.0/classes.jar \
    --new library-3.4.0/classes.jar \
    --html-file index.html \
    --ignore-missing-classes \
    

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73. JAPICMP CLI
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    --old library-3.3.0/classes.jar \
    --new library-3.4.0/classes.jar \
    --html-file index.html \
    --include “com.chuckerteam.chucker.api” \
    --include-exclusively
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    --old library-3.3.0/classes.jar \
    --new library-3.4.0/classes.jar \
    --html-file index.html \
    --ignore-missing-classes \
    --no-annotations \
    

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74. JAPICMP CLI
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    --old library-3.3.0/classes.jar \
    --new library-3.4.0/classes.jar \
    --html-file index.html \
    --include “com.chuckerteam.chucker.api” \
    --include-exclusively
    java -jar japicmp-0.14.4-jar-with-dependencies.jar \
    --old library-3.3.0/classes.jar \
    --new library-3.4.0/classes.jar \
    --html-file index.html \
    --ignore-missing-classes \
    --no-annotations \
    --exclude “com.chuckerteam.chucker.databinding;
    com.chuckerteam.chucker.internal"
    

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75. JAPICMP HTML REPORT
    

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76. JAPICMP HTML REPORT
    

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77. JAPICMP HTML REPORT
    

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78. JAPICMP HTML REPORT
    

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79. JAPICMP HTML REPORT
    

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80. JAPICMP HTML REPORT
    

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81. JAPICMP HTML REPORT
    

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82. JAPICMP HTML REPORT
    

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83. JAPICMP HTML REPORT
    

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84. JAPICMP HTML REPORT
    

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85. JAPICMP GRADLE SETUP
    apply plugin: "me.champeau.gradle.japicmp"
    

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86. JAPICMP GRADLE SETUP
    apply plugin: "me.champeau.gradle.japicmp"
    configurations {
    latest
    baseline
    }
    

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87. JAPICMP GRADLE SETUP
    apply plugin: "me.champeau.gradle.japicmp"
    configurations {
    latest
    baseline
    }
    dependencies {
    }
    

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88. JAPICMP GRADLE SETUP
    apply plugin: "me.champeau.gradle.japicmp"
    configurations {
    latest
    baseline
    }
    dependencies {
    baseline project(path: ":library", configuration: "default")
    }
    

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89. JAPICMP GRADLE SETUP
    apply plugin: "me.champeau.gradle.japicmp"
    configurations {
    latest
    baseline
    }
    dependencies {
    baseline project(path: ":library", configuration: "default")
    latest("com.github.chuckerteam.chucker:library:3.4.0")
    }
    

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90. JAPICMP GRADLE SETUP
    apply plugin: "me.champeau.gradle.japicmp"
    configurations {
    latest
    baseline
    }
    dependencies {
    baseline project(path: ":library", configuration: "default")
    latest("com.github.chuckerteam.chucker:library:3.4.0") {
    transitive = false
    force = true
    }
    }
    

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91. apply plugin: "me.champeau.gradle.japicmp"
    configurations {
    latest
    baseline
    }
    dependencies {
    baseline project(path: ":library", configuration: "default")
    latest("com.github.chuckerteam.chucker:library:3.4.0") {
    transitive = false
    force = true
    }
    }
    tasks.register("japiCmp", JapicmpTask) {
    oldClasspath = configurations.latest
    newClasspath = configurations.baseline
    }
    JAPICMP GRADLE SETUP
    

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92. apply plugin: "me.champeau.gradle.japicmp"
    configurations {
    latest
    baseline
    }
    dependencies {
    baseline project(path: ":library", configuration: "default")
    latest("com.github.chuckerteam.chucker:library:3.4.0") {
    transitive = false
    force = true
    }
    }
    tasks.register("japiCmp", JapicmpTask) {
    oldClasspath = configurations.latest
    newClasspath = configurations.baseline
    htmlOutputFile = file("$buildDir/reports/japiCmp.html")
    }
    JAPICMP GRADLE SETUP
    

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93. apply plugin: "me.champeau.gradle.japicmp"
    configurations {
    latest
    baseline
    }
    dependencies {
    baseline project(path: ":library", configuration: "default")
    latest("com.github.chuckerteam.chucker:library:3.4.0") {
    transitive = false
    force = true
    }
    }
    tasks.register("japiCmp", JapicmpTask) {
    oldClasspath = configurations.latest
    newClasspath = configurations.baseline
    htmlOutputFile = file("$buildDir/reports/japiCmp.html")
    failOnModification = true
    }
    JAPICMP GRADLE SETUP
    

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94. apply plugin: "me.champeau.gradle.japicmp"
    configurations {
    latest
    baseline
    }
    dependencies {
    baseline project(path: ":library", configuration: "default")
    latest("com.github.chuckerteam.chucker:library:3.4.0") {
    transitive = false
    force = true
    }
    }
    tasks.register("japiCmp", JapicmpTask) {
    oldClasspath = configurations.latest
    newClasspath = configurations.baseline
    htmlOutputFile = file("$buildDir/reports/japiCmp.html")
    failOnModification = true
    ignoreMissingClasses = true
    }
    JAPICMP GRADLE SETUP
    

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95. configurations {
    latest
    baseline
    }
    dependencies {
    baseline project(path: ":library", configuration: "default")
    latest("com.github.chuckerteam.chucker:library:3.4.0") {
    transitive = false
    force = true
    }
    }
    tasks.register("japiCmp", JapicmpTask) {
    oldClasspath = configurations.latest
    newClasspath = configurations.baseline
    htmlOutputFile = file("$buildDir/reports/japiCmp.html")
    failOnModification = true
    ignoreMissingClasses = true
    packageIncludes = ["com.chuckerteam.chucker.api"]
    }
    JAPICMP GRADLE SETUP
    

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96. configurations {
    latest
    baseline
    }
    dependencies {
    baseline project(path: ":library", configuration: "default")
    latest("com.github.chuckerteam.chucker:library:3.4.0") {
    transitive = false
    force = true
    }
    }
    tasks.register("japiCmp", JapicmpTask) {
    oldClasspath = getJarClasses(project, configurations.latest)
    newClasspath = getJarClasses(project, configurations.baseline)
    htmlOutputFile = file("$buildDir/reports/japiCmp.html")
    failOnModification = true
    ignoreMissingClasses = true
    packageIncludes = ["com.chuckerteam.chucker.api"]
    }
    JAPICMP GRADLE SETUP
    

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97. latest("com.github.chuckerteam.chucker:library:3.4.0") {
    transitive = false
    force = true
    }
    }
    tasks.register("japiCmp", JapicmpTask) {
    oldClasspath = getJarClasses(project, configurations.latest)
    newClasspath = getJarClasses(project, configurations.baseline)
    htmlOutputFile = file("$buildDir/reports/japiCmp.html")
    failOnModification = true
    ignoreMissingClasses = true
    packageIncludes = ["com.chuckerteam.chucker.api"]
    }
    def getJarClasses(project, configuration) {
    return project.files(
    project.zipTree(configuration.files.first())
    .matching {include "classes.jar"}
    .first()
    )
    }
    JAPICMP GRADLE SETUP
    

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98. TO RECAP
    

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99. TO RECAP Evolving APIs is HARD
    

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100. TO RECAP Evolving APIs is HARD
     

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101. TO RECAP Evolving APIs is HARD
     

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102. TO RECAP Evolving APIs is HARD
     

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103. TO RECAP
     • binary-compatibility-validator
     • Safeguard your API during your workflow
     • Easier to integrate for Kotlin/Gradle projects
     • japicmp
     • Fine grain control over your API surface
     • Useful when making a new release
     • Be a good API citizen
     

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104. THANKS
     @CORTINICO
     

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