Groovy in the light of Java 8 -- JavaOne 2014

With Java 8 out, what is the impact of Groovy? Is it still relevant? How can developers can benefit from Java 8 with Groovy?

Transcript

1. Groovy in the light of Java 8 Guillaume Laforge Groovy project lead Pivotal @glaforge
2. Stay up-to-date Groovy Weekly Newsletter (Every Tuesday) http://beta.groovy-lang.org/groovy-weekly.html 2
3. @glaforge — Groovy in the light of Java 8 Goal of this talk
4. A recurring question… Do we still need Groovy now that we have Java 8? 4
5. To those who said no… 5
6. But more precisely… • Will Java lambdas replace Groovy closures? • What are the differences between them? ! • Will Groovy support all the new Java 8 language constructs? • lambdas, default methods, method references… ! • How Groovy developers can benefit from Java 8? ! • What does Groovy offer beyond Java 8? 6
7. What about redundancy? ! ! ! ! ! • Closures • Traits • Truth & null handling • Functional with collections • Method closures ! ! ! ! ! ! • Lambdas • Default methods • Optional • Stream API • Method references 7
8. @glaforge — Groovy in the light of Java 8 What’s new in Java 8?
10. This is not a Java 8 crash courses with all the details :-)
11. This is not a Java 8 crash courses with all the details :-) We want to understand the implications with regards to Groovy
12. What’s new in Java 8? ! • New syntax • Streams • Profiles • Security enhancements • JavaFX • Tools • i18n • Date / time API • Nashorn / JavaScript ! ! • Pack200 • IO / NIO improvements • New utility classes • JDBC • Networking • Concurrency • JAXP • Hotspot • Java Mission Control 10
13. What’s new in Java 8? ! • New syntax • Streams • Profiles • Security enhancements • JavaFX • Tools • i18n • Date / time API • Nashorn / JavaScript ! ! • Pack200 • IO / NIO improvements • New utility classes • JDBC • Networking • Concurrency • JAXP • Hotspot • Java Mission Control 10 Great concise resource with the whole list: http://bit.ly/new-in-java-8
14. @glaforge — Groovy in the light of Java 8 Support the new Java 8 language features New Java 8 syntax
15. New Java 8 syntax constructs • Lambda expressions • Method references • Static & default methods in interfaces • Repeating annotations • Annotations on types • Improved type inference • Method parameter reflection 12
16. New Java 8 syntax constructs • Lambda expressions • Method references • Static & default methods in interfaces • Repeating annotations • Annotations on types • Improved type inference • Method parameter reflection 13
20. Lambda expressions 15 double highestScore = students .filter(Student s -> s.getGradYear() == 2011) .map(Student s -> s.getScore()) .max();
21. Lambda expressions 16 double highestScore = students .filter(Student s -> s.getGradYear() == 2011) .map(Student s -> s.getScore()) .max();
22. Lambda expressions 16 double highestScore = students .filter(Student s -> s.getGradYear() == 2011) .map(Student s -> s.getScore()) .max(); Coercion into a Predicate « functional interface »
23. Lambda expressions 16 double highestScore = students .filter(Student s -> s.getGradYear() == 2011) .map(Student s -> s.getScore()) .max(); There’s no function type!
24. Lambda expressions 16 double highestScore = students .filter(Student s -> s.getGradYear() == 2011) .map(Student s -> s.getScore()) .max(); Pipeline being built Single pass!
25. Lambda expressions 16 double highestScore = students .filter(Student s -> s.getGradYear() == 2011) .map(Student s -> s.getScore()) .max();
26. Lambda expressions 17 double highestScore = students .findAll { it.gradYear == 2011 } .collect { it.score} .max()
27. Lambda expressions 17 double highestScore = students .findAll { it.gradYear == 2011 } .collect { it.score} .max() In Groovy, that would be…
28. Lambda expressions 17 double highestScore = students .findAll { it.gradYear == 2011 } .collect { it.score} .max() Drawback: intermediary data structures Unless you use iterator variants
29. Lambda expressions 17 double highestScore = students .findAll { it.gradYear == 2011 } .collect { it.score} .max()
30. The various lambda syntaxes 18 String name -> name.length() ! (int left, int right) -> left + right ! (String left, String sep, String right) -> { System.out.println(left + sep + right) }
31. The various lambda syntaxes 18 String name -> name.length() ! (int left, int right) -> left + right ! (String left, String sep, String right) -> { System.out.println(left + sep + right) } One parameter: no parens Expression on right: no curly
32. The various lambda syntaxes 18 String name -> name.length() ! (int left, int right) -> left + right ! (String left, String sep, String right) -> { System.out.println(left + sep + right) } Parentheses required for more that one parameter
33. The various lambda syntaxes 18 String name -> name.length() ! (int left, int right) -> left + right ! (String left, String sep, String right) -> { System.out.println(left + sep + right) } Statements require curly braces Return keyword required if non-void returning
34. The various lambda syntaxes 18 String name -> name.length() ! (int left, int right) -> left + right ! (String left, String sep, String right) -> { System.out.println(left + sep + right) } Clever type inference can help get rid of parameter type declarations
35. Closures vs lambdas 19 IntStream.range(1, 100).forEach(s -> System.out.println(s)); ! Files.lines(Paths.get('README.adoc')) .map(it -> it.toUpperCase()) .forEach(it -> System.out.println(it));
36. Closures vs lambdas 19 IntStream.range(1, 100).forEach(s -> System.out.println(s)); ! Files.lines(Paths.get('README.adoc')) .map(it -> it.toUpperCase()) .forEach(it -> System.out.println(it)); IntStream.range(1, 100).forEach { println it } ! Files.lines(Paths.get('README.adoc')) .map { it.toUpperCase() } .forEach { println it }
37. Closures vs lambdas 19 IntStream.range(1, 100).forEach(s -> System.out.println(s)); ! Files.lines(Paths.get('README.adoc')) .map(it -> it.toUpperCase()) .forEach(it -> System.out.println(it)); IntStream.range(1, 100).forEach { println it } ! Files.lines(Paths.get('README.adoc')) .map { it.toUpperCase() } .forEach { println it } Use Groovy closures wherever you pass lambdas in Java 8
38. Closures vs lambdas 19 IntStream.range(1, 100).forEach(s -> System.out.println(s)); ! Files.lines(Paths.get('README.adoc')) .map(it -> it.toUpperCase()) .forEach(it -> System.out.println(it)); IntStream.range(1, 100).forEach { println it } ! Files.lines(Paths.get('README.adoc')) .map { it.toUpperCase() } .forEach { println it } Groovy coerces to SAM types (Single Abstract Method)
39. Closures vs lambdas 19 IntStream.range(1, 100).forEach(s -> System.out.println(s)); ! Files.lines(Paths.get('README.adoc')) .map(it -> it.toUpperCase()) .forEach(it -> System.out.println(it)); IntStream.range(1, 100).forEach { println it } ! Files.lines(Paths.get('README.adoc')) .map { it.toUpperCase() } .forEach { println it }
40. Beyond: Closure default parameters 20 def mult = { int a, int b = 10 -> a * b } ! assert mult(2, 3) == 6 assert mult(5) == 50
41. Beyond: Closure default parameters 20 def mult = { int a, int b = 10 -> a * b } ! assert mult(2, 3) == 6 assert mult(5) == 50 Default value if the parameter is not specified
42. Beyond: Duck typing polymorphism 21 def adder = { a, b -> a + b } ! assert adder(100, 200) == 300 assert adder('X', 'Y') == 'XY'
43. Beyond: Duck typing polymorphism 21 def adder = { a, b -> a + b } ! assert adder(100, 200) == 300 assert adder('X', 'Y') == 'XY' Works both for numbers and for strings
44. Builders
45. Builders What would Java lambda builders look like?
46. Builders What would Java lambda builders look like? Aren’t Groovy builders more powerful?
47. Lambda-based builders uglier and less powerful 23 MarkupBuilder pom = new XmlMarkupBuilder() pom.el("modelVersion", "4.0.0"); pom.el("groupId", "com.github"); pom.el("artifactId", "lambda-builder"); pom.el("version", "1.0-SNAPSHOT"); pom.el("dependencies", () -> { pom.el("dependency", () -> { pom.el("groupId", "junit"); pom.el("artifactId", "junit"); pom.elx("version", "4.11"); }); pom.el("dependency", () -> { pom.el("groupId", "commons-beanutils"); pom.el("artifactId", "commons-beanutils"); pom.elx("version", "1.7.0"); }); });
48. Lambda-based builders uglier and less powerful 23 MarkupBuilder pom = new XmlMarkupBuilder() pom.el("modelVersion", "4.0.0"); pom.el("groupId", "com.github"); pom.el("artifactId", "lambda-builder"); pom.el("version", "1.0-SNAPSHOT"); pom.el("dependencies", () -> { pom.el("dependency", () -> { pom.el("groupId", "junit"); pom.el("artifactId", "junit"); pom.elx("version", "4.11"); }); pom.el("dependency", () -> { pom.el("groupId", "commons-beanutils"); pom.el("artifactId", "commons-beanutils"); pom.elx("version", "1.7.0"); }); }); Repeated « pom »: No delegate like in Groovy’s closures
49. Lambda-based builders uglier and less powerful 23 MarkupBuilder pom = new XmlMarkupBuilder() pom.el("modelVersion", "4.0.0"); pom.el("groupId", "com.github"); pom.el("artifactId", "lambda-builder"); pom.el("version", "1.0-SNAPSHOT"); pom.el("dependencies", () -> { pom.el("dependency", () -> { pom.el("groupId", "junit"); pom.el("artifactId", "junit"); pom.elx("version", "4.11"); }); pom.el("dependency", () -> { pom.el("groupId", "commons-beanutils"); pom.el("artifactId", "commons-beanutils"); pom.elx("version", "1.7.0"); }); }); Zero-arg lamdas not as lean
50. Lambda-based builders uglier and less powerful 23 MarkupBuilder pom = new XmlMarkupBuilder() pom.el("modelVersion", "4.0.0"); pom.el("groupId", "com.github"); pom.el("artifactId", "lambda-builder"); pom.el("version", "1.0-SNAPSHOT"); pom.el("dependencies", () -> { pom.el("dependency", () -> { pom.el("groupId", "junit"); pom.el("artifactId", "junit"); pom.elx("version", "4.11"); }); pom.el("dependency", () -> { pom.el("groupId", "commons-beanutils"); pom.el("artifactId", "commons-beanutils"); pom.elx("version", "1.7.0"); }); }); Generic method + string: No dynamic method
51. Neater Groovy builder! 24 def pom = new PomBuilder().project { modelVersion "4.0.0" groupId "com.github" artifactId "lambda-builder" version "1.0-SNAPSHOT" dependencies { dependency { groupId "junit" artifactId "junit" version "4.11" } dependency { groupId "commons-beanutils" artifactId "commons-beanutils" version "1.7.0" } } }
52. Neater Groovy builder! 24 def pom = new PomBuilder().project { modelVersion "4.0.0" groupId "com.github" artifactId "lambda-builder" version "1.0-SNAPSHOT" dependencies { dependency { groupId "junit" artifactId "junit" version "4.11" } dependency { groupId "commons-beanutils" artifactId "commons-beanutils" version "1.7.0" } } }
54. Aren’t Groovy builders more readable and lean?
55. To those who said no… 26
56. Memoization
57. Closure and method memoization 28 def fib2 = { long n -> if (n < 2) 1 else call(n - 1) + call(n - 2) }.memoize()
58. Closure and method memoization 28 def fib2 = { long n -> if (n < 2) 1 else call(n - 1) + call(n - 2) }.memoize() Closures: memoize()
59. Closure and method memoization 28 @Memoized long fib(long n) { if (n < 2) 1 else fib(n - 1) + fib(n - 2) } def fib2 = { long n -> if (n < 2) 1 else call(n - 1) + call(n - 2) }.memoize() Closures: memoize()
60. Closure and method memoization 28 @Memoized long fib(long n) { if (n < 2) 1 else fib(n - 1) + fib(n - 2) } def fib2 = { long n -> if (n < 2) 1 else call(n - 1) + call(n - 2) }.memoize() Closures: memoize() Methods: memoization AST transformation
62. Tail recursion
63. Closure and method tail recursion 30 def fact = { n, accu = 1G -> if (n < 2) accu else fact.trampoline(n - 1, n * accu) }.trampoline()
64. Closure and method tail recursion 30 def fact = { n, accu = 1G -> if (n < 2) accu else fact.trampoline(n - 1, n * accu) }.trampoline() Closures: Tail recursion with trampoline()
65. Closure and method tail recursion 30 @groovy.transform.TailRecursive def fact(n, accu = 1G) { if (n < 2) accu else fact(n - 1, n * accu) } def fact = { n, accu = 1G -> if (n < 2) accu else fact.trampoline(n - 1, n * accu) }.trampoline() Closures: Tail recursion with trampoline()
66. Closure and method tail recursion 30 @groovy.transform.TailRecursive def fact(n, accu = 1G) { if (n < 2) accu else fact(n - 1, n * accu) } def fact = { n, accu = 1G -> if (n < 2) accu else fact.trampoline(n - 1, n * accu) }.trampoline() Closures: Tail recursion with trampoline() Methods: Tail recursion with @TailRecursive transformation
67. Method references 31 button.setOnAction(event -> System.out.println(event));
68. Method references 31 button.setOnAction(event -> System.out.println(event)); button.setOnAction(System.out::println);
69. Method references — 3 main cases • Three main cases: 32 instance::instanceMethod ! SomeClass::staticMethod ! SomeClass::instanceMethod
70. Method references — 3 main cases • Three main cases: 32 instance::instanceMethod ! SomeClass::staticMethod ! SomeClass::instanceMethod Not covered by Groovy method closures yet!
71. Groovy’s method closure 33 instance.&instanceMethod ! SomeClass.&staticMethod ! SomeClass.&instanceMethod
72. Groovy’s method closure 33 instance.&instanceMethod ! SomeClass.&staticMethod ! SomeClass.&instanceMethod Choices: Adopt :: Deprecate .& Enhance .&
73. Static methods in interfaces • You can put static utility methods in interfaces, 
 instead of in companion classes (like « Collections ») 34 public interface Stream<T> { // ... static <T> Stream<T> empty() { return new Stream<T> { ... } } }
74. Default methods in interfaces • Define default behavior • possibly to enrich existing interfaces 35 public interface Stream<T> { // ... default Builder<T> add(T t) { ... } }
75. Groovy Traits • Like interfaces, but with method bodies • similar to Java 8 interface default methods • Elegant way to compose behavior • multiple inheritance without the « diamond » problem • Traits can also be stateful • traits can have properties like normal classes • Compatible with static typing and static compilation • class methods from traits also visible from Java classes • Also possible to implement traits at runtime 36
76. Simple trait 37 trait FlyingAbility { String fly() { "I'm flying!" } } ! class Bird implements FlyingAbility {} def b = new Bird() ! assert b.fly() == "I'm flying!"
77. Trait with state 38 trait Named { String name } ! class Bird implements Named {} def b = new Bird(name: 'Colibri') ! assert b.name == 'Colibri'
78. Multiple inheritance 39 trait KiteSurfer { String surf() { 'kite' } } ! trait WebSurfer { String surf() { 'web' } } ! class Person { String name } ! class Hipster extends Person implements KiteSurfer, WebSurfer {} ! def h = new Hipster() assert h.surf() == 'web'
79. Annotations on types Repeating annotations
80. Repeating annotations 41 @Schedule(dayOfMonth = "last") @Schedule(dayOfWeek = "Fri", hour = 23) public void doPeriodicCleanup() { ... }
81. Repeating annotations 41 @Schedule(dayOfMonth = "last") @Schedule(dayOfWeek = "Fri", hour = 23) public void doPeriodicCleanup() { ... } @Schedule annotation repeated twice
82. Repeating annotations 41 @Schedule(dayOfMonth = "last") @Schedule(dayOfWeek = "Fri", hour = 23) public void doPeriodicCleanup() { ... } @Repeatable(Schedules.class) public @interface Schedule { String dayOfMonth() default "first"; String dayOfWeek() default "Mon"; int hour() default 12; }
83. Repeating annotations 41 @Schedule(dayOfMonth = "last") @Schedule(dayOfWeek = "Fri", hour = 23) public void doPeriodicCleanup() { ... } @Repeatable(Schedules.class) public @interface Schedule { String dayOfMonth() default "first"; String dayOfWeek() default "Mon"; int hour() default 12; } Container annotation for the repeated annotationd
84. Repeating annotations 41 @Schedule(dayOfMonth = "last") @Schedule(dayOfWeek = "Fri", hour = 23) public void doPeriodicCleanup() { ... } @Repeatable(Schedules.class) public @interface Schedule { String dayOfMonth() default "first"; String dayOfWeek() default "Mon"; int hour() default 12; } public @interface Schedules { Schedule[] value(); }
85. Repeating annotations 41 @Schedule(dayOfMonth = "last") @Schedule(dayOfWeek = "Fri", hour = 23) public void doPeriodicCleanup() { ... } @Repeatable(Schedules.class) public @interface Schedule { String dayOfMonth() default "first"; String dayOfWeek() default "Mon"; int hour() default 12; } public @interface Schedules { Schedule[] value(); } The container annotation iteself
86. Repeating annotations 41 @Schedule(dayOfMonth = "last") @Schedule(dayOfWeek = "Fri", hour = 23) public void doPeriodicCleanup() { ... } @Repeatable(Schedules.class) public @interface Schedule { String dayOfMonth() default "first"; String dayOfWeek() default "Mon"; int hour() default 12; } public @interface Schedules { Schedule[] value(); }
87. Repeating annotations 41 @Schedule(dayOfMonth = "last") @Schedule(dayOfWeek = "Fri", hour = 23) public void doPeriodicCleanup() { ... } @Repeatable(Schedules.class) public @interface Schedule { String dayOfMonth() default "first"; String dayOfWeek() default "Mon"; int hour() default 12; } public @interface Schedules { Schedule[] value(); } Not yet supported
88. Repeating annotations 41 @Schedule(dayOfMonth = "last") @Schedule(dayOfWeek = "Fri", hour = 23) public void doPeriodicCleanup() { ... } @Repeatable(Schedules.class) public @interface Schedule { String dayOfMonth() default "first"; String dayOfWeek() default "Mon"; int hour() default 12; } public @interface Schedules { Schedule[] value(); }
89. Annotations on types • Everywhere you can put a type, you can put an annotation 42 @NonNull String name; ! email = (@Email String) input; ! List<@NonNull String> names; ! new @Interned MyObject(); ! void monitorTemperature() throws @Critical TemperatureException { ... } ! class UnmodifiableList<T> implements @Readonly List<@Readonly T> {...}
90. Annotations on types • Everywhere you can put a type, you can put an annotation 42 @NonNull String name; ! email = (@Email String) input; ! List<@NonNull String> names; ! new @Interned MyObject(); ! void monitorTemperature() throws @Critical TemperatureException { ... } ! class UnmodifiableList<T> implements @Readonly List<@Readonly T> {...} Not yet supported
91. Annotations on types • Everywhere you can put a type, you can put an annotation 42 @NonNull String name; ! email = (@Email String) input; ! List<@NonNull String> names; ! new @Interned MyObject(); ! void monitorTemperature() throws @Critical TemperatureException { ... } ! class UnmodifiableList<T> implements @Readonly List<@Readonly T> {...} Imagine the potential for targets for local AST transformations?
92. Annotations on types • Everywhere you can put a type, you can put an annotation 42 @NonNull String name; ! email = (@Email String) input; ! List<@NonNull String> names; ! new @Interned MyObject(); ! void monitorTemperature() throws @Critical TemperatureException { ... } ! class UnmodifiableList<T> implements @Readonly List<@Readonly T> {...}
93. Groovy compile-time meta-annotations 43 @Service @Transactional class MyTransactionalService {}
94. Groovy compile-time meta-annotations 43 @Service @Transactional class MyTransactionalService {} import groovy.transform.AnnotationCollector ! @Service @Transactional @AnnotationCollector public @interface TransactionalService {}
95. Groovy compile-time meta-annotations 43 import groovy.transform.AnnotationCollector ! @Service @Transactional @AnnotationCollector public @interface TransactionalService {} ! @TransactionalService class MyTransactionalService {}
96. Groovy compile-time meta-annotations 43 import groovy.transform.AnnotationCollector ! @Service @Transactional @AnnotationCollector public @interface TransactionalService {} ! @TransactionalService class MyTransactionalService {} Can handle parameters (even conflicting), or you can create your own « processor »
97. Groovy compile-time meta-annotations 43 import groovy.transform.AnnotationCollector ! @Service @Transactional @AnnotationCollector public @interface TransactionalService {} ! @TransactionalService class MyTransactionalService {}
98. @glaforge — Groovy in the light of Java 8 New Java 8 APIs
99. Date and Time API
100. Date / Time API 46 LocalDate.now(); today.with(TemporalAdjusters.lastDayOfMonth()).minusDays(2); ! LocalDate.of(2012, Month.MAY, 14); dateOfBirth.plusYears(1); ! LocalDate date = LocalDate.of(2000, Month.NOVEMBER, 20); LocalDate nextWed = date.with(TemporalAdjusters.next(DayOfWeek.WEDNESDAY));
101. Date / Time API 46 LocalDate.now(); today.with(TemporalAdjusters.lastDayOfMonth()).minusDays(2); ! LocalDate.of(2012, Month.MAY, 14); dateOfBirth.plusYears(1); ! LocalDate date = LocalDate.of(2000, Month.NOVEMBER, 20); LocalDate nextWed = date.with(TemporalAdjusters.next(DayOfWeek.WEDNESDAY)); Groovy could add some operator overloading?
102. Date / Time API 46 LocalDate.now(); today.with(TemporalAdjusters.lastDayOfMonth()).minusDays(2); ! LocalDate.of(2012, Month.MAY, 14); dateOfBirth.plusYears(1); ! LocalDate date = LocalDate.of(2000, Month.NOVEMBER, 20); LocalDate nextWed = date.with(TemporalAdjusters.next(DayOfWeek.WEDNESDAY));
103. Groovy’s date / time handling 47 import static java.util.Calendar.* import groovy.time.* import org.codehaus.groovy.runtime.TimeCategory ! def cal = Calendar.instance cal.set(year: 2010, month: JULY, date: 9) ! assert FRIDAY == cal[DAY_OF_WEEK] ! use (TimeCategory) { 2.years + 3.months + 15.days + 23.minutes + 2.seconds ! 1.week - 1.day new Date() + 6.days ! 3.days.ago new Date() - 3 }
104. Groovy’s date / time handling 47 import static java.util.Calendar.* import groovy.time.* import org.codehaus.groovy.runtime.TimeCategory ! def cal = Calendar.instance cal.set(year: 2010, month: JULY, date: 9) ! assert FRIDAY == cal[DAY_OF_WEEK] ! use (TimeCategory) { 2.years + 3.months + 15.days + 23.minutes + 2.seconds ! 1.week - 1.day new Date() + 6.days ! 3.days.ago new Date() - 3 } Groovy could provide the same for Date / Time
105. Groovy’s date / time handling 47 import static java.util.Calendar.* import groovy.time.* import org.codehaus.groovy.runtime.TimeCategory ! def cal = Calendar.instance cal.set(year: 2010, month: JULY, date: 9) ! assert FRIDAY == cal[DAY_OF_WEEK] ! use (TimeCategory) { 2.years + 3.months + 15.days + 23.minutes + 2.seconds ! 1.week - 1.day new Date() + 6.days ! 3.days.ago new Date() - 3 }
106. Stream API
107. map map map map map reduce reduce reduce reduce reduce
108. map map map map map reduce reduce reduce reduce reduce Map / filter / reduce explained to your 6 year old
109. map map map map map reduce reduce reduce reduce reduce
110. Stream 50 persons.stream() .filter( p -> p.getAge() < 18 ) .map( p -> p.getName().toUpperCase() ) .sorted() .collect(Collectors.joining(", "));
111. Groovy’s functional style with the GDK methods 51 persons .findAll { it.getAge() < 18 } .collect { it.name.toUpperCase() } .sort() .joining(", ")
112. Groovy using streams too! 52 persons.stream() .filter { it.age < 18 } .map { it.name.toUpperCase() } .sorted() .collect(Collectors.joining(", "))
113. Groovy using streams too! 52 persons.stream() .filter { it.age < 18 } .map { it.name.toUpperCase() } .sorted() .collect(Collectors.joining(", ")) Leveraging closure to « SAM » type coercion
114. Groovy using streams too! 52 persons.stream() .filter { it.age < 18 } .map { it.name.toUpperCase() } .sorted() .collect(Collectors.joining(", "))
115. Optional 53 Optional<String> maybeName = Optional.of("Guillaume"); ! String result = maybeName.orElse("unknown") ! if (maybeName.ifPresent()) { System.out.println(maybeName.get()); } else { System.out.println("unknown"); }
116. Optional 53 Optional<String> maybeName = Optional.of("Guillaume"); ! String result = maybeName.orElse("unknown") ! if (maybeName.ifPresent()) { System.out.println(maybeName.get()); } else { System.out.println("unknown"); } Wrap something that can be potentially null
117. Optional 53 Optional<String> maybeName = Optional.of("Guillaume"); ! String result = maybeName.orElse("unknown") ! if (maybeName.ifPresent()) { System.out.println(maybeName.get()); } else { System.out.println("unknown"); }
118. Optional 53 Optional<String> maybeName = Optional.of("Guillaume"); ! String result = maybeName.orElse("unknown") ! if (maybeName.ifPresent()) { System.out.println(maybeName.get()); } else { System.out.println("unknown"); } Force handling the null value
119. Optional 53 Optional<String> maybeName = Optional.of("Guillaume"); ! String result = maybeName.orElse("unknown") ! if (maybeName.ifPresent()) { System.out.println(maybeName.get()); } else { System.out.println("unknown"); }
121. You know you can customize the truth in Groovy?
122. You know you can customize the truth in Groovy? Just implement a custom asBoolean() method!
123. The law of Groovy Truth 55
124. The law of Groovy Truth 55 Everything that’s null, empty, zero-sized, equal to zero is false
125. The law of Groovy Truth 55 Everything that’s null, empty, zero-sized, equal to zero is false Otherwise, it’s true!
126. ?:
127. Groovy truth, null handling, Elvis with Optional 57 def maybeName = Optional.of("Guillaume") ! def result = maybeName ?: "unknown" ! if (maybeName) { println maybeName.get() } else { println "unknown" } ! maybeName?.toUpperCase()
128. Groovy truth, null handling, Elvis with Optional 57 def maybeName = Optional.of("Guillaume") ! def result = maybeName ?: "unknown" ! if (maybeName) { println maybeName.get() } else { println "unknown" } ! maybeName?.toUpperCase() Elvis!
129. Groovy truth, null handling, Elvis with Optional 57 def maybeName = Optional.of("Guillaume") ! def result = maybeName ?: "unknown" ! if (maybeName) { println maybeName.get() } else { println "unknown" } ! maybeName?.toUpperCase() Groovy Truth!
130. Groovy truth, null handling, Elvis with Optional 57 def maybeName = Optional.of("Guillaume") ! def result = maybeName ?: "unknown" ! if (maybeName) { println maybeName.get() } else { println "unknown" } ! maybeName?.toUpperCase() Safe navigation
131. Groovy truth, null handling, Elvis with Optional 57 def maybeName = Optional.of("Guillaume") ! def result = maybeName ?: "unknown" ! if (maybeName) { println maybeName.get() } else { println "unknown" } ! maybeName?.toUpperCase() Interesting discussions on the mailing-list to further enhance usage of Optional from Groovy
132. Groovy truth, null handling, Elvis with Optional 57 def maybeName = Optional.of("Guillaume") ! def result = maybeName ?: "unknown" ! if (maybeName) { println maybeName.get() } else { println "unknown" } ! maybeName?.toUpperCase() Not Yet Implemented
133. Groovy truth, null handling, Elvis with Optional 57 def maybeName = Optional.of("Guillaume") ! def result = maybeName ?: "unknown" ! if (maybeName) { println maybeName.get() } else { println "unknown" } ! maybeName?.toUpperCase()
134. Nashorn
135. Nashorn Speak German?
136. Call JavaScript from Groovy with JSR-223 59 def manager = new ScriptEngineManager() def engine = manager.getEngineByName("nashorn") ! assert engine.eval("{} + []") == 0
137. Call JavaScript from Groovy with JSR-223 59 def manager = new ScriptEngineManager() def engine = manager.getEngineByName("nashorn") ! assert engine.eval("{} + []") == 0 Sane JavaScript logic :-)
138. GrooScript — http://grooscript.org/ 60 JS
139. GrooScript — http://grooscript.org/ 60 JS Gradle & Grails plugins available Examples available with Ratpack, Node.JS…
140. Turtles all the way down!
141. Turtles all the way down! Full Groovy!
142. Turtles all the way down! Full Groovy! Back to front
143. Turtles all the way down! Full Groovy! Back to front Front to back
144. JavaFx… ! ! …the new Swing
145. GroovyFX 63 import javafx.scene.Scene import static groovyx.javafx.GroovyFX.start ! def chamber = ["5 Stelle": 108, "Italia.\nBene commune": 340, "Con Monti per l'Italia": 45, "Berlusconi": 124, "others": 4] ! start { stage(title: 'Italian chamber of Deputies', width: 1024, height: 700, visible: true) { Scene s = scene { tilePane { barChart(barGap: 10, categoryGap: 20, title: "Italy's election in February 2013") { series(name: 'Chamber (seats)', data: ['5 Stelle', 17.5, 'Monti', 7.8, 'Bene commune', 55, 'Berlusconi', 19.9]) series(name: 'Senate (seats)', data: ['5 Stelle', 17.4, 'Monti', 6.1, 'Bene commune', 39.1, 'Berlusconi', 37.1]) } pieChart(data: chamber, title: "Chamber of Deputies") } } s.stylesheets.add("Chart.css") } }
146. GroovyFX 63 import javafx.scene.Scene import static groovyx.javafx.GroovyFX.start ! def chamber = ["5 Stelle": 108, "Italia.\nBene commune": 340, "Con Monti per l'Italia": 45, "Berlusconi": 124, "others": 4] ! start { stage(title: 'Italian chamber of Deputies', width: 1024, height: 700, visible: true) { Scene s = scene { tilePane { barChart(barGap: 10, categoryGap: 20, title: "Italy's election in February 2013") { series(name: 'Chamber (seats)', data: ['5 Stelle', 17.5, 'Monti', 7.8, 'Bene commune', 55, 'Berlusconi', 19.9]) series(name: 'Senate (seats)', data: ['5 Stelle', 17.4, 'Monti', 6.1, 'Bene commune', 39.1, 'Berlusconi', 37.1]) } pieChart(data: chamber, title: "Chamber of Deputies") } } s.stylesheets.add("Chart.css") } } Groovy builder to the rescue!
147. @glaforge — Groovy in the light of Java 8 Beyond Java
148. @glaforge — Groovy in the light of Java 8 Android
149. Android support • You can use Groovy to code Android apps! • use Groovy 2.4.0-beta-1+ • prefer @CompileStatic ! • Two great posts to get started: • http://melix.github.io/blog/2014/06/grooid.html • http://melix.github.io/blog/2014/06/grooid2.html 66
150. New York Times — Getting Groovy with Android 67
151. New York Times — Getting Groovy with Android 67 http://bit.ly/nyt-groovy
152. What does NYT likes about Groovy on Android? • No Java 8, no lambda on Android… 68 Func0 func = new Func0<string>() { @Override public String call() { return "my content"; } }; Async.start(func);
153. What does NYT likes about Groovy on Android? • No Java 8, no lambda on Android… 69 ! ! ! ! ! ! Async.start { "my content" }
154. What does NYT likes about Groovy on Android? • No Java 8, no lambda on Android… 69 ! ! ! ! ! ! Async.start { "my content" } Good bye annonymous inner classes!
155. What does NYT likes about Groovy on Android? ! • Groovy code more concise and more readable ! • but just as type-safe as needed!
 (with @TypeChecked) ! • but just as fast as needed!
 (with @CompileStatic) 70
156. Android support 71
157. Android support 71 Source code available: https://github.com/melix/gr8confagenda
158. @glaforge — Groovy in the light of Java 8 A rich Groovy ecosystem
159. Grails — web framework 73 @Grab("com.h2database:h2:1.3.173") import grails.persistence.* ! @Entity @Resource(uri='/books') class Book { String title }
160. Grails — web framework 73 @Grab("com.h2database:h2:1.3.173") import grails.persistence.* ! @Entity @Resource(uri='/books') class Book { String title } One class, one command, and you’ve got a full REST CRUD application!
161. Ratpack — web framework 74 @GrabResolver("https://oss.jfrog.org/artifactory/repo") @Grab("org.ratpack-framework:ratpack-groovy:0.9.8") import static org.ratpackframework.groovy.RatpackScript.ratpack import static org.ratpackframework.groovy.Template.groovyTemplate ! ratpack { handlers { get { response.send "Welcome!" } ! get("date") { render groovyTemplate("date.html") } ! assets "public" } }
162. Ratpack — web framework 74 @GrabResolver("https://oss.jfrog.org/artifactory/repo") @Grab("org.ratpack-framework:ratpack-groovy:0.9.8") import static org.ratpackframework.groovy.RatpackScript.ratpack import static org.ratpackframework.groovy.Template.groovyTemplate ! ratpack { handlers { get { response.send "Welcome!" } ! get("date") { render groovyTemplate("date.html") } ! assets "public" } } Lightweight Netty-based web application toolkit
163. @ArtifactProviderFor(GriffonModel) class ConsoleModel { String scriptSource @Observable Object scriptResult @Observable boolean enabled = true } Griffon — rich desktop applications 75
164. @ArtifactProviderFor(GriffonModel) class ConsoleModel { String scriptSource @Observable Object scriptResult @Observable boolean enabled = true } Griffon — rich desktop applications 75 Model
165. @ArtifactProviderFor(GriffonModel) class ConsoleModel { String scriptSource @Observable Object scriptResult @Observable boolean enabled = true } Griffon — rich desktop applications 75 Model @ArtifactProviderFor(GriffonController) class ConsoleController { def model ! @Inject Evaluator evaluator ! void executeScript() { model.enabled = false def result try { result = evaluator.evaluate(model.scriptSource) } finally { model.enabled = true model.scriptResult = result } } } Controller
166. @ArtifactProviderFor(GriffonModel) class ConsoleModel { String scriptSource @Observable Object scriptResult @Observable boolean enabled = true } Griffon — rich desktop applications 75 Model @ArtifactProviderFor(GriffonController) class ConsoleController { def model ! @Inject Evaluator evaluator ! void executeScript() { model.enabled = false def result try { result = evaluator.evaluate(model.scriptSource) } finally { model.enabled = true model.scriptResult = result } } } Controller application(title: application.configuration['application.title'], pack: true, locationByPlatform: true, id: 'mainWindow', iconImage: imageIcon('/griffon-icon-48x48.png').image, iconImages: [imageIcon('/griffon-icon-48x48.png').image, imageIcon('/griffon-icon-32x32.png').image, imageIcon('/griffon-icon-16x16.png').image]) { panel(border: emptyBorder(6)) { borderLayout() scrollPane(constraints: CENTER) { textArea(text: bind(target: model, 'scriptSource'), enabled: bind { model.enabled }, columns: 40, rows: 10) } ! hbox(constraints: SOUTH) { button(executeScriptAction) hstrut(5) label('Result:') hstrut(5) textField(editable: false, text: bind { model.scriptResult }) } } } View
167. Spock — unit testing & specification 76 @Grab('org.spockframework:spock-core:0.7-groovy-2.0') import spock.lang.* ! class MathSpec extends Specification { def "maximum of two numbers"() { expect: Math.max(a, b) == c ! where: a | b || c 1 | 3 || 3 7 | 4 || 7 0 | 0 || 0 } }
168. Spock — unit testing & specification 76 @Grab('org.spockframework:spock-core:0.7-groovy-2.0') import spock.lang.* ! class MathSpec extends Specification { def "maximum of two numbers"() { expect: Math.max(a, b) == c ! where: a | b || c 1 | 3 || 3 7 | 4 || 7 0 | 0 || 0 } } Readable & concise expectations
169. Spock — unit testing & specification 76 @Grab('org.spockframework:spock-core:0.7-groovy-2.0') import spock.lang.* ! class MathSpec extends Specification { def "maximum of two numbers"() { expect: Math.max(a, b) == c ! where: a | b || c 1 | 3 || 3 7 | 4 || 7 0 | 0 || 0 } } Readable & concise expectations Awesome data-driven tests with a wiki-like notation
170. Geb — browser automation 77 import geb.Browser ! Browser.drive { go "http://myapp.com/login" ! assert $("h1").text() == "Please Login" ! $("form.login").with { username = "admin" password = "password" login().click() } ! assert $("h1").text() == 
 "Admin Section" }
171. Geb — browser automation 77 import geb.Browser ! Browser.drive { go "http://myapp.com/login" ! assert $("h1").text() == "Please Login" ! $("form.login").with { username = "admin" password = "password" login().click() } ! assert $("h1").text() == 
 "Admin Section" } Drive your browser
172. Geb — browser automation 77 import geb.Browser ! Browser.drive { go "http://myapp.com/login" ! assert $("h1").text() == "Please Login" ! $("form.login").with { username = "admin" password = "password" login().click() } ! assert $("h1").text() == 
 "Admin Section" } Drive your browser JQuery-like selectors
173. Geb — browser automation 77 import geb.Browser ! Browser.drive { go "http://myapp.com/login" ! assert $("h1").text() == "Please Login" ! $("form.login").with { username = "admin" password = "password" login().click() } ! assert $("h1").text() == 
 "Admin Section" } Drive your browser JQuery-like selectors Fill & submit forms
174. Gradle — build automation 78 apply plugin: 'java' apply plugin: 'eclipse' ! sourceCompatibility = 1.5 version = '1.0' jar { manifest { attributes 'Implementation-Title': 'Gradle Quickstart' } } ! repositories { mavenCentral() } ! dependencies { compile ‘commons-collections:commons-collections:3.2’ testCompile 'junit:junit:4.+' } ! uploadArchives { repositories { flatDir { dirs 'repos' } } }
175. Gradle — build automation 78 apply plugin: 'java' apply plugin: 'eclipse' ! sourceCompatibility = 1.5 version = '1.0' jar { manifest { attributes 'Implementation-Title': 'Gradle Quickstart' } } ! repositories { mavenCentral() } ! dependencies { compile ‘commons-collections:commons-collections:3.2’ testCompile 'junit:junit:4.+' } ! uploadArchives { repositories { flatDir { dirs 'repos' } } } Powerful and readable DSL for automating your builds and deployments
176. GPars — concurrency / parallelism / async / … 79 import static groovyx.gpars.actor.Actors.actor ! def decryptor = actor { loop { react { message -> if (message instanceof String) reply message.reverse() else stop() } } } ! def console = actor { decryptor.send 'lellarap si yvoorG' react { println 'Decrypted message: ${it}' decryptor.send false } } ! [decryptor, console]*.join()
177. GPars — concurrency / parallelism / async / … 79 import static groovyx.gpars.actor.Actors.actor ! def decryptor = actor { loop { react { message -> if (message instanceof String) reply message.reverse() else stop() } } } ! def console = actor { decryptor.send 'lellarap si yvoorG' react { println 'Decrypted message: ${it}' decryptor.send false } } ! [decryptor, console]*.join() Actors…
178. GPars — concurrency / parallelism / async / … 79 import static groovyx.gpars.actor.Actors.actor ! def decryptor = actor { loop { react { message -> if (message instanceof String) reply message.reverse() else stop() } } } ! def console = actor { decryptor.send 'lellarap si yvoorG' react { println 'Decrypted message: ${it}' decryptor.send false } } ! [decryptor, console]*.join() Actors… But also: Dataflow concurrency, CSP, agents, concurrent collection processing, fork / join, composable async functions, STM
179. @glaforge — Groovy in the light of Java 8 Groovy modules
180. Groovy modules • Ant scripting • JMX • JSON • Servlet • Swing • SQL • Templating • Testing • XML 81
181. Groovy modules • Ant scripting • JMX • JSON • Servlet • Swing • SQL • Templating • Testing • XML 82
182. Ant + XML 83 def writer = new StringWriter() def mkp = new MarkupBuilder(writer) ! mkp.html { head { title 'Build notification' } body { p 'Your build was successful' } } ! new AntBuilder().mail(mailhost: 'localhost', messagemimetype: 'text/html', subject: 'Build successful') { ! from address: 'ci@mycomp.com' to address: 'me@mycomp.com' message writer attchments { fileset(dir: 'dist') { include name: '**/logs*.txt' } } }
183. Ant + XML 83 def writer = new StringWriter() def mkp = new MarkupBuilder(writer) ! mkp.html { head { title 'Build notification' } body { p 'Your build was successful' } } ! new AntBuilder().mail(mailhost: 'localhost', messagemimetype: 'text/html', subject: 'Build successful') { ! from address: 'ci@mycomp.com' to address: 'me@mycomp.com' message writer attchments { fileset(dir: 'dist') { include name: '**/logs*.txt' } } } Generate some HTML with the XML support
184. Ant + XML 83 def writer = new StringWriter() def mkp = new MarkupBuilder(writer) ! mkp.html { head { title 'Build notification' } body { p 'Your build was successful' } } ! new AntBuilder().mail(mailhost: 'localhost', messagemimetype: 'text/html', subject: 'Build successful') { ! from address: 'ci@mycomp.com' to address: 'me@mycomp.com' message writer attchments { fileset(dir: 'dist') { include name: '**/logs*.txt' } } } Generate some HTML with the XML support Use the Ant builder and the mail task
185. Ant + XML 83 def writer = new StringWriter() def mkp = new MarkupBuilder(writer) ! mkp.html { head { title 'Build notification' } body { p 'Your build was successful' } } ! new AntBuilder().mail(mailhost: 'localhost', messagemimetype: 'text/html', subject: 'Build successful') { ! from address: 'ci@mycomp.com' to address: 'me@mycomp.com' message writer attchments { fileset(dir: 'dist') { include name: '**/logs*.txt' } } } Generate some HTML with the XML support Use the Ant builder and the mail task Use the Ant’s fileset
186. JSON support — creating JSON 84 import groovy.json.* ! def json = new JsonBuilder() json.person { name 'Guillaume' age 37 daughters 'Marion', 'Erine' address { street '1 Main Street' zip 75001 city 'Paris' } }
187. JSON support — creating JSON 84 import groovy.json.* ! def json = new JsonBuilder() json.person { name 'Guillaume' age 37 daughters 'Marion', 'Erine' address { street '1 Main Street' zip 75001 city 'Paris' } } { "person": { "name": "Guillaume", "age": 37, "daughters": [ "Marion", "Erine" ], "address": { "street": "1 Main Street", "zip": 75001, "city": "Paris" } } }
188. JSON support — parsing JSON 85 import groovy.json.* ! def url = 
 "https://api.github.com/repos/groovy/groovy-core/commits" ! def commits = new JsonSlurper().parseText(url.toURL().text) ! assert commits[0].commit.author.name == 'Cedric Champeau'
189. JSON support — parsing JSON 85 import groovy.json.* ! def url = 
 "https://api.github.com/repos/groovy/groovy-core/commits" ! def commits = new JsonSlurper().parseText(url.toURL().text) ! assert commits[0].commit.author.name == 'Cedric Champeau' The power of a dynamic language!
190. Template module — new markup template engine • Based on the principles of Groovy’s « builders » • and particularly the MarkupBuilder class
 for generating arbitrary XML / HTML payloads ! • Compiled statically for fast template rendering ! • Internationalization aware • provide the desired Locale in the configuration object • usual suffix notation template_fr_FR.tpl ! • Custom base template class • ability to provide reusable methods across your templates 86
191. Template module — new markup template engine • Based on the principles of Groovy’s « builders » • and particularly the MarkupBuilder class
 for generating arbitrary XML / HTML payloads ! • Compiled statically for fast template rendering ! • Internationalization aware • provide the desired Locale in the configuration object • usual suffix notation template_fr_FR.tpl ! • Custom base template class • ability to provide reusable methods across your templates 86 Spring Boot approved
192. Markup template engine — the idea 87 cars { cars.each { car(make: it.make, name: it.name) } }
193. Markup template engine — the idea 87 cars { cars.each { car(make: it.make, name: it.name) } } Your template
194. Markup template engine — the idea 87 cars { cars.each { car(make: it.make, name: it.name) } } model = [cars: [ new Car(make: 'Peugeot', name: '508'), new Car(make: 'Toyota', name: 'Prius’) ]]
195. Markup template engine — the idea 87 cars { cars.each { car(make: it.make, name: it.name) } } model = [cars: [ new Car(make: 'Peugeot', name: '508'), new Car(make: 'Toyota', name: 'Prius’) ]] Feed a model into your template
196. Markup template engine — the idea 87 cars { cars.each { car(make: it.make, name: it.name) } } model = [cars: [ new Car(make: 'Peugeot', name: '508'), new Car(make: 'Toyota', name: 'Prius’) ]] <cars> <car make='Peugeot' name='508'/> <car make='Toyota' name='Prius'/> </cars>
197. Markup template engine — the idea 87 cars { cars.each { car(make: it.make, name: it.name) } } model = [cars: [ new Car(make: 'Peugeot', name: '508'), new Car(make: 'Toyota', name: 'Prius’) ]] <cars> <car make='Peugeot' name='508'/> <car make='Toyota' name='Prius'/> </cars> Generate the XML output
198. Markup template engine — the idea 87 cars { cars.each { car(make: it.make, name: it.name) } } model = [cars: [ new Car(make: 'Peugeot', name: '508'), new Car(make: 'Toyota', name: 'Prius’) ]] <cars> <car make='Peugeot' name='508'/> <car make='Toyota' name='Prius'/> </cars>
199. Markup template engine — in action 88 import  groovy.text.markup.*   ! def  config  =  new  TemplateConfiguration()   def  engine  =  new  MarkupTemplateEngine(config)   def  tmpl  =  engine.createTemplate('''          p("Hello  ${model.name}")   ''')   def  model  =  [name:  'World']   System.out  <<  tmpl.make(model)
200. @glaforge — Groovy in the light of Java 8 Summary
201. Back to our original question… Do we still need Groovy now that we have Java 8? 90
203. Longer answer: Yes, because… • You can benefit from Java 8 in Groovy 92 Synergy
 the whole is 
 greater than the sum of the parts
204. Longer answer: Yes, because… • Groovy goes beyond what Java 8 offers 93 Beyond
 Groovy always tries to add something to the table
205. Questions still open: Syntax support for… • lambdas • not necessarily,
 (confusing / duplication) ! • method references • enhance method closures • or replace them with method references ! • interface default methods • yes: traits methods aren’t default methods • repeated annotations • yes: not urgent • but less boilerplate is good ! • annotations on type • yes: opens up new possibilities for targets of local AST transformation ! • interface static methods • yes: for Java compatibility 94
206. Further possible API enhancements • Make Optional Groovy-friendly • with regards to Groovy Truth • accessing the wrapped value ! • More Groovy methods for… • NIO • Streams • Date / time ! • Operator overloading for Date / time • for arithmetics on instants and durations 95
207. Further possible API enhancements • Make Optional Groovy-friendly • with regards to Groovy Truth • accessing the wrapped value ! • More Groovy methods for… • NIO • Streams • Date / time ! • Operator overloading for Date / time • for arithmetics on instants and durations 95 Community feedback & contributions welcome!
208. @glaforge — Groovy in the light of Java 8 Q & A
210. Image credits • Question mark • http://www.mynamesnotmommy.com/wp-content/uploads/2013/05/question-mark.png • Get out! • http://static.comicvine.com/uploads/original/11/117995/3772037-0075368930-27616.jpg • Yes • http://soloprpro.com/wp-content/uploads/2013/08/yes.jpg • Synergy • http://www.wildblueberries.com/wp-content/uploads/blogger/_YhH8fDK5-kU/S_5kYWwgAbI/AAAAAAAAAKU/JQ_-ISfT9KY/s1600/ teamwork.jpg • Buzz Lightyear • http://www.disneypictures.net/data/media/202/Buzz_Lightyear_hd.jpg • Start wars spaceship • http://swc.fs2downloads.com/media/screenshots/Support_Trans/Shuttle/lambda003.jpg • Lambda character • http://lambda.ninjackaton.ninja-squad.com/images/lambda.png • Man clock • http://3.bp.blogspot.com/-7hLQ9tnmA84/TuTIoLRLMTI/AAAAAAAABWM/g7ahyLCRjJQ/s1600/Harold+Lloyd+Safety+Last.jpg • Stream • http://wallpaperswide.com/forest_stream-wallpapers.html • Nashorn (rhino) • http://2010sdafrika.files.wordpress.com/2012/07/hi_257587-nashorn-c-naturepl-com-mark-carwardine-wwf-canon.jpg 98
211. Image credits • Brain • http://www.semel.ucla.edu/sites/all/files/users/user-412/dreamstime_xxl_17754591%20(2).jpg • Many thanks • http://www.trys.ie/wp-content/uploads/2013/06/many-thanks.jpg • Swing • http://makemesomethingspecial.co.uk/wp-content/uploads/2012/10/Solid-Oak-Handmade-Spliced-Swing-With-Personalised- Engraving-10867.jpg • Disclaimer • http://3.bp.blogspot.com/-RGnBpjXTCQA/Tj2h_JsLigI/AAAAAAAABbg/AB5ZZYzuE5w/s1600/disclaimer.jpg • Hammer / justice / truth • http://www.bombayrealty.in/images/disclaimer.jpg • Law • http://www.permanentmakeupbymv.com/wp-content/uploads/2014/07/law-2.jpg • Glasses / readable • http://a.fastcompany.net/multisite_files/coexist/imagecache/1280/poster/2013/02/1681393-poster-1280-responsive-eye-chart.jpg • We need you • http://www.bostonbreakerssoccer.com/imgs/ABOUT/volopps/we%20need%20you.JPG • Golden Gate • http://www.airpano.com/files/San-Francisco-Golden-Gate-USA/sf_golden_gate.jpg 99
212. Image credits • Turtles • http://33.media.tumblr.com/77095e3a37acb2272133c405b1f7ba54/tumblr_myfydjNgXJ1s20kxvo1_1280.jpg • Annotations • http://3.bp.blogspot.com/-f94n9BHko_s/T35ELs7nYvI/AAAAAAAAAKg/qe06LRPH9U4/s1600/IMG_1721.JPG • Builders • http://detroittraining.com/wp-content/uploads/Construction-Women2.jpg • Sandwich ingredients • http://www.fromages-de-terroirs.com/IMG/MEULE_DETOUREE_72_DPI_-2.jpg • http://eboutique-hebergement.orange-business.com/WebRoot/Orange/Shops/Madeinalsace/4B02/6320/943E/DB4F/DDBF/ 0A0A/33E8/4BC8/iStock_000008775559XSmall.jpg • http://www.cmonprimeur.fr/images/25834-vegetable-pictures%5B1%5D.jpg • http://1.bp.blogspot.com/-27UoqYeYtY4/T4PAr4zGSnI/AAAAAAAAA3s/lleE-NOh0LE/s1600/IMG_1528.JPG • http://www.growingpatch.com/wp-content/uploads/2014/05/tomato-9.jpg • http://vitaminsandhealthsupplements.com/wp-content/uploads/2013/08/fresh-sliced-tomato.jpg • http://2.bp.blogspot.com/-3pPmRhBHv9s/T3D-EtLlN1I/AAAAAAAAAgg/Y5oTM84nGb8/s1600/cochon+2.jpg • http://www.salamarket.fr/wp-content/uploads/steak-hach%C3%A9.jpg • http://www.quinzanisbakery.com/images/bread-vienna.jpg • http://www.saucissonvaudois.qc.ca/images/produits/Jambon_blanc.jpg • http://www.audion.com/system/public/categories/125/images/bread-sandwich.jpg 100