AutoValue Extensions (Square NYC, March 2016)

Google's AutoValue library provides easy value types in Java through code generation and its forthcoming release has a powerful new feature: extensions. This talk will introduce the extensions feature, cover useful extensions for Android, and offer tips for building your own.

Video: https://www.youtube.com/watch?v=Kl2xZufgW14

Transcript

1. Jake Wharton AutoValue Extensions
2. AutoValue @AutoValue public abstract class Payment {
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X
3. AutoValue @AutoValue
 public abstract class Payment { 
 public static Payment create(
 long id, long amount, Currency currency, String note) {
 return new AutoValue_Payment(id, amount, currency, note);
 }Z
 
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X
4. AutoValue @AutoValue
 public abstract class Payment { 
 public static Payment create(
 long id, long amount, Currency currency, String note) {
 return new AutoValue_Payment(id, amount, currency, note);
 }Z
 
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X
5. AutoValue Extensions @AutoValue
 public abstract class Payment { 
 public static Payment create(
 long id, long amount, Currency currency, String note) {
 return new AutoValue_Payment(id, amount, currency, note);
 }Z
 
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X final class AutoValue_Payment extends Payment {
 private final long id;
 private final long amount;
 private final Currency currency;
 private final String note;
 
 AutoValue_Payment(long id, long amount, Currency currency, String note) {
 this.id = id;
 this.amount = amount;
 this.currency = currency;
 this.note = note;
 }Q
 
 @Override public long id() {
 return id;
 }Y
 @Override public long amount() {
 return amount;
 }Z
 @Override public Currency currency() {
 return currency;
 }U
 @Override public String note() {
 return note;
 }W
 
 @Override public String toString() {
 return "Payment{" +
 "id=" + id +
 ", amount=" + amount +
 ", currency=" + currency +
 ", note='" + note + '\'' +
 '}';
 }E
 
 @Override public boolean equals(Object o) {
 if (this == o) return true;
 if (!(o instanceof Payment)) return false;
 Payment other = (Payment) o;
 return id == other.id
 && amount == other.amount
 && currency.equals(other.currency)
 && note.equals(other.note);
 }R
 
 @Override public int hashCode() {
 int result = (int) (id ^ (id >>> 32));
 result = 31 * result + (int) (amount ^ (amount >>> 32));
 result = 31 * result + currency.hashCode();
 result = 31 * result + note.hashCode();
 return result;
 }T
 }X
6. @AutoValue public abstract class Payment {
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X AutoValue Extensions
7. @AutoValue public abstract class Payment {
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X Ok, awesome! Now how do I use it with ? Parcelable AutoValue Extensions
8. @AutoValue public abstract class Payment {
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X Ok, awesome! Now how do I use it with ? Parcelable Gson AutoValue Extensions
9. @AutoValue public abstract class Payment {
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X Ok, awesome! Now how do I use it with ? Parcelable Gson Cursors AutoValue Extensions
10. @AutoValue public abstract class Payment {
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X Ok, awesome! Now how do I use it with ? Parcelable Gson Cursors (whatever) AutoValue Extensions
11. @AutoValue public abstract class Payment {
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X Ok, awesome! Now how do I use it with ? Parcelable Gson Cursors (whatever) AutoValue Extensions
12. AutoValue @AutoValue public abstract class Payment3{
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X AutoValue Extensions
13. AutoValue Extensions @AutoValue public abstract class Payment1implements2Parcelable3{3
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X /* abstract properties */
14. AutoValue Extensions @AutoValue public abstract class Payment1implements2Parcelable3{3 /* abstract properties */ }X final class AutoValue_Payment1extends2Payment { /* value type implementation */ }Y
15. AutoValue Extensions final class AutoValue_Payment1extends2$AutoValue_Payment { /* parcelable implementation */ }Z abstract class $AutoValue_Payment1extends2Payment { /* value type implementation */ }Y @AutoValue public abstract class Payment1implements2Parcelable { /* abstract properties */ }X
16. final class AutoValue_Payment1extends2$AutoValue_Payment { /* parcelable implementation */ }Z /* abstract properties */ abstract class $AutoValue_Payment1extends2Payment { /* value type implementation */ }Y AutoValue Extensions @AutoValue public abstract class Payment1implements2Parcelable3{3
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 public abstract String note();
 }X /* abstract properties */
17. final class AutoValue_Payment1extends2$AutoValue_Payment { /* parcelable implementation */ }Z /* abstract properties */ abstract class $AutoValue_Payment1extends2Payment { /* value type implementation */ }Y AutoValue Extensions @AutoValue public abstract class Payment1implements2Parcelable3{3
 public abstract long id();
 public abstract long amount();
 public abstract Currency currency();
 @Redacted public abstract String note();
 }X /* abstract properties */
18. AutoValue Extensions final class AutoValue_Payment1extends2$AutoValue_Payment { /* parcelable implementation */ }Z abstract class $AutoValue_Payment1extends2Payment { /* value type implementation */ }Y @AutoValue public abstract class Payment1implements2Parcelable { /* abstract properties */ }X
19. AutoValue Extensions final class AutoValue_Payment1extends2$AutoValue_Payment { /* parcelable implementation */ }Z abstract class $AutoValue_Payment1extends2$$AutoValue_Payment { /* value type implementation (without toString) */ }Y abstract class $$AutoValue_Payment1extends2Payment { /* redacted toString implementation */ }Y @AutoValue public abstract class Payment1implements2Parcelable { /* abstract properties */ }X
20. AutoValue Extensions final class AutoValue_Payment1extends2$AutoValue_Payment { /* parcelable implementation */ }Z abstract class $AutoValue_Payment1extends2$$AutoValue_Payment { /* value type implementation (without toString) */ }Y abstract class $$AutoValue_Payment1extends2Payment { /* redacted toString implementation */ }Y @AutoValue public abstract class Payment1implements2Parcelable { /* abstract properties */ }X
21. AutoValue Extensions final class AutoValue_Payment1extends2$AutoValue_Payment { /* parcelable implementation */ }Z abstract class $AutoValue_Payment1extends2$$AutoValue_Payment { /* value type implementation (without toString) */ }Y abstract class $$AutoValue_Payment1extends2Payment { /* redacted toString implementation */ }Y @AutoValue public abstract class Payment1implements2Parcelable { /* abstract properties */ }X
22. AutoValue Extensions final class AutoValue_Payment1extends2$AutoValue_Payment { /* parcelable implementation */ }Z abstract class $AutoValue_Payment1extends2$$AutoValue_Payment { /* value type implementation (without toString) */ }Y abstract class $$AutoValue_Payment1extends2Payment { /* redacted toString implementation */ }Y @AutoValue public abstract class Payment1implements2Parcelable { /* abstract properties */ }X
23. AutoValue Extensions final class AutoValue_Payment1extends2$AutoValue_Payment { /* parcelable implementation */ }Z abstract class $AutoValue_Payment1extends2$$AutoValue_Payment { /* value type implementation (without toString) */ }Y abstract class $$AutoValue_Payment1extends2Payment { /* redacted toString implementation */ }Y @AutoValue public abstract class Payment1implements2Parcelable { /* abstract properties */ }X
24. Available Extensions • Parcelable: github.com/rharter/auto-value-parcel • Redacted: github.com/square/auto-value-redacted • Gson: github.com/rharter/auto-value-gson • Moshi: github.com/rharter/auto-value-moshi • Cursor: github.com/gabrielittner/auto-value-cursor • "with"ers: github.com/gabrielittner/auto-value-with
25. Extension API
26. Extension API public abstract class AutoValueExtension {
 public boolean applicable(Context context) {
 return false;
 }
 
 public boolean mustBeFinal(Context context) {
 return false;
 }
 
 public Set<String> consumeProperties(Context context) {
 return Collections.emptySet();
 }
 
 public abstract String generateClass(Context context, String className, String classToExtend, boolean isFinal);
 }
27. Extension API public abstract class AutoValueExtension {
 public boolean applicable(Context context) {
 return false;
 }X
 
 public boolean mustBeFinal(Context context) {
 return false;
 }
 
 public Set<String> consumeProperties(Context context) {
 return Collections.emptySet();
 }
 
 public abstract String generateClass(Context context, String className, String classToExtend, boolean isFinal);
 }
28. Extension API public boolean applicable(Context context)
29. Extension API public boolean applicable(Context context) Parcelable extension @AutoValue public abstract class Payment {}
30. Extension API public boolean applicable(Context context) Parcelable extension @AutoValue public abstract class Payment {} false
31. Extension API public boolean applicable(Context context) Parcelable extension Parcelable extension @AutoValue public abstract class Payment {} @AutoValue public abstract class Payment implements Parcelable {} false
32. Extension API public boolean applicable(Context context) Parcelable extension Parcelable extension @AutoValue public abstract class Payment {} @AutoValue public abstract class Payment implements Parcelable {} false true
33. Extension API public boolean applicable(Context context) Parcelable extension Parcelable extension Redacted extension @AutoValue public abstract class Payment {} @AutoValue public abstract class Payment implements Parcelable {} @AutoValue public abstract class Payment { public abstract String note(); } false true
34. Extension API public boolean applicable(Context context) Parcelable extension Parcelable extension Redacted extension @AutoValue public abstract class Payment {} @AutoValue public abstract class Payment implements Parcelable {} @AutoValue public abstract class Payment { public abstract String note(); } false true false
35. Extension API public boolean applicable(Context context) Parcelable extension Parcelable extension Redacted extension Redacted extension @AutoValue public abstract class Payment {} @AutoValue public abstract class Payment implements Parcelable {} @AutoValue public abstract class Payment { public abstract String note(); } @AutoValue public abstract class Payment { @Redacted public abstract String note(); } false true false
36. Extension API public boolean applicable(Context context) Parcelable extension Parcelable extension Redacted extension Redacted extension @AutoValue public abstract class Payment {} @AutoValue public abstract class Payment implements Parcelable {} @AutoValue public abstract class Payment { public abstract String note(); } @AutoValue public abstract class Payment { @Redacted public abstract String note(); } false true false true
37. Extension API public boolean applicable(Context context) false true
38. Extension API public boolean applicable(Context context) false true final class AutoValue_Payment1extends2Payment { /* value type implementation */ }Y @AutoValue public abstract class Payment1{3 /* abstract properties */ }X final class AutoValue_Payment1extends2$AutoValue_Payment { /* value type implementation */ }Y abstract class $AutoValue_Payment1extends2Payment { /* extension implementation */ }Y @AutoValue public abstract class Payment1{3 /* abstract properties */ }X
39. Extension API public abstract class AutoValueExtension {
 public boolean applicable(Context context) {
 return false;
 }X
 
 public boolean mustBeFinal(Context context) {
 return false;
 }
 
 public Set<String> consumeProperties(Context context) {
 return Collections.emptySet();
 }
 
 public abstract String generateClass(Context context, String className, String classToExtend, boolean isFinal);
 }
40. Extension API public abstract class AutoValueExtension {
 public boolean applicable(Context context) {
 return false;
 }
 
 public boolean mustBeFinal(Context context) {
 return false;
 }
 
 public Set<String> consumeProperties(Context context) {
 return Collections.emptySet();
 }
 
 public abstract String generateClass(Context context, String className, String classToExtend, boolean isFinal);
 }
41. Extension API public boolean mustBeFinal(Context context)
42. Extension API public boolean mustBeFinal(Context context) Parcelable extension true
43. Extension API public boolean mustBeFinal(Context context) Parcelable extension true All* other extensions false
44. Extension API public boolean mustBeFinal(Context context) false true
45. Extension API public boolean mustBeFinal(Context context) false true final class AutoValue_Payment1extends2$AutoValue_Payment { /* extension implementation */ }Y abstract class $AutoValue_Payment1extends2Payment { /* value type implementation */ }Y @AutoValue public abstract class Payment1{3 /* abstract properties */ }X final class AutoValue_Payment1extends2$AutoValue_Payment { /* value type implementation */ }Y abstract class $AutoValue_Payment1extends2Payment { /* extension implementation */ }Y @AutoValue public abstract class Payment1{3 /* abstract properties */ }X
46. Extension API public boolean mustBeFinal(Context context) false true final class AutoValue_Payment1extends2$AutoValue_Payment { /* extension implementation */ }Y abstract class $AutoValue_Payment1extends2Payment { /* value type implementation */ }Y @AutoValue public abstract class Payment1{3 /* abstract properties */ }X final class AutoValue_Payment1extends2$AutoValue_Payment { /* value type implementation */ }Y abstract class $AutoValue_Payment1extends2Payment { /* extension implementation */ }Y @AutoValue public abstract class Payment1{3 /* abstract properties */ }X
47. Extension API public abstract class AutoValueExtension {
 public boolean applicable(Context context) {
 return false;
 }
 
 public boolean mustBeFinal(Context context) {
 return false;
 }
 
 public Set<String> consumeProperties(Context context) {
 return Collections.emptySet();
 }
 
 public abstract String generateClass(Context context, String className, String classToExtend, boolean isFinal);
 }
48. Extension API public abstract class AutoValueExtension {
 public boolean applicable(Context context) {
 return false;
 }
 
 public boolean mustBeFinal(Context context) {
 return false;
 }
 
 public Set<String> consumeProperties(Context context) {
 return Collections.emptySet();
 }
 
 public abstract String generateClass(Context context, String className, String classToExtend, boolean isFinal);
 }
49. Extension API public Set<String> consumeProperties(Context context)
50. Extension API public Set<String> consumeProperties(Context context) @AutoValue public abstract class Payment implements Parcelable { public abstract String note(); }
51. Extension API public Set<String> consumeProperties(Context context) @AutoValue public abstract class Payment implements Parcelable { public abstract String note(); } Extension [ ]
52. Extension API public Set<String> consumeProperties(Context context) @AutoValue public abstract class Payment implements Parcelable { public abstract String note(); } Extension [ ] [ "note", "describeContents" ]
53. Extension API public Set<String> consumeProperties(Context context) @AutoValue public abstract class Payment implements Parcelable { public abstract String note(); } Extension [ ] [ "note", "describeContents" ] @AutoValue public abstract class Payment implements Parcelable { public abstract String note(); } Extension [ "describeContents" ] [ "note" ]
54. Extension API public abstract class AutoValueExtension {
 public boolean applicable(Context context) {
 return false;
 }
 
 public boolean mustBeFinal(Context context) {
 return false;
 }
 
 public Set<String> consumeProperties(Context context) {
 return Collections.emptySet();
 }
 
 public abstract String generateClass(Context context, String className, String classToExtend, boolean isFinal);
 }
55. Extension API public abstract class AutoValueExtension {
 public boolean applicable(Context context) {
 return false;
 }
 
 public boolean mustBeFinal(Context context) {
 return false;
 }
 
 public Set<String> consumeProperties(Context context) {
 return Collections.emptySet();
 }
 
 public abstract String generateClass(Context context, String className, String classToExtend, boolean isFinal);
 }
56. Building Extensions
57. Building Extensions • Model it after the existing extensions
58. Building Extensions • Model it after the existing extensions • Try to play nice with other extensions
59. Building Extensions • Model it after the existing extensions • Try to play nice with other extensions • JavaPoet: github.com/square/javapoet • Truth: github.com/google/truth • compile-testing: github.com/google/compile-testing • auto/service: github.com/google/auto
60. 1.2-SNAPSHOT?!?
61. 1.2-SNAPSHOT?!? Big Bang (not to scale)
62. 1.2-SNAPSHOT?!? Big Bang AutoValue 1.1 released (10 months ago) (not to scale)
63. 1.2-SNAPSHOT?!? Big Bang AutoValue 1.1 released (10 months ago) Extensions merged (9 months ago) (not to scale)
64. 1.2-SNAPSHOT?!? Big Bang AutoValue 1.1 released (10 months ago) Extensions merged (9 months ago) (not to scale)
65. 1.2-SNAPSHOT?!? Big Bang Heat death of universe AutoValue 1.1 released (10 months ago) Extensions merged (9 months ago) AutoValue 1.2 released ?????? (not to scale)
66. jakewharton jakewharton jakewharton twitter.com/ google.com/+ .com AutoValue Extensions