It seems like keeping up to date with Java nowadays is an enormous task. Gone is the era of big, delayed Java releases that span years. We're now getting a new major release every six months. What's up with that? You're probably still developing on Java 8, even though Java 12 is already available. Join this session to get a code-first overview of what's new in Java since Java 8. We'll give an overview of the module system (Java 9), the local-variable type inference feature (Java 10), the new HttpClient API (Java 11) and a sneak peek of Switch Expressions in Java 12. Expect lots of advice on what to expect when migrating beyond Java 8. It's time to embrace the newfound agility of the Java platform!

1. By Sander Mak
Coding Your Way
@Sander_Mak
to Java 12

2. About Sander
Fellow, Software Architect
@ Luminis
Experience in modular
development stacks
Conference Speaker & Author

3. @Sander_Mak
Java
9
(Sept. 2017)

4. @Sander_Mak
Quick Java Module Overview

5. @Sander_Mak
module main {
}
module-info.java
Module Declarations

6. @Sander_Mak
module main {
}
module-info.java
Module Declarations
main.web
main.persistence
main.integration
main

7. @Sander_Mak
module main {
requires helper;
}
module-info.java
module helper {
}
module-info.java
Explicit Dependencies
main.web
main.persistence
main.integration
main

8. @Sander_Mak
module main {
requires helper;
}
module-info.java
module helper {
}
module-info.java
helper
Explicit Dependencies
main.web
main.persistence
main.integration
main

9. @Sander_Mak
module main {
requires helper;
}
module helper {
exports helper.api;
}
module-info.java module-info.java
helper.api
helper
Well-defined Interfaces
main.web
main.persistence
main.integration
main

10. @Sander_Mak
module main {
requires helper;
}
module helper {
exports helper.api;
}
module-info.java module-info.java
helper.api
helper.impl
helper
Strong Encapsulation
main.web
main.persistence
main.integration
main

11. @Sander_Mak
Demo: EasyText
easytext.cli
easytext.analysis

12. @Sander_Mak
Why?

13. @Sander_Mak
Why?
Modular JDK

14. @Sander_Mak
Why?
Modular JDK
Maintainability
Reliable composition
Flexibility

15. @Sander_Mak
quick refresher
why/advantages
(JDK: modularized, your app: architecture from whiteboard to code, explicit dependencies in language, strong encapsulation, jlink
Why?
Decrease the model-code gap

16. @Sander_Mak
jlink

17. @Sander_Mak
jlink
+
main
lib1 lib2
jdk
~300mb
application
~2mb

18. @Sander_Mak
jlink
+
main
lib1 lib2
jdk
~300mb
application
~2mb JVM
main
lib1 lib2
java.base
java.logging
java.xml
Custom Run-time Image
~25mb

19. @Sander_Mak
jlink
+
main
lib1 lib2
jdk
~300mb
application
~2mb JVM
main
lib1 lib2
java.base
java.logging
java.xml
Custom Run-time Image

20. @Sander_Mak
IoT Device
jlink
+
main
lib1 lib2
jdk
~300mb
application
~2mb JVM
main
lib1 lib2
java.base
java.logging
java.xml
Custom Run-time Image

21. @Sander_Mak
Impact on Java 8 codebases

22. @Sander_Mak
Impact on Java 8 codebases
Use of encapsulated JDK types:
Run-time warnings
Compile-time errors

23. @Sander_Mak
Impact on Java 8 codebases
Use of encapsulated JDK types:
Run-time warnings
Compile-time errors
Use of enterprise APIs in JDK:
Won't resolve by default
Gone in Java 11!
java.corba
java.xml.bind
java.xml.ws.*
java.activation
java.transaction

24. @Sander_Mak
R
jshell
E
P
L

25. @Sander_Mak
R
jshell
E
P
L
ead

26. @Sander_Mak
R
jshell
E
P
L
ead
val

27. @Sander_Mak
R
jshell
E
P
L
ead
val
rint

28. @Sander_Mak
R
jshell
E
P
L
ead
val
rint
oop

29. @Sander_Mak
R
jshell
E
P
L
ead
val
rint
oop
Input code

30. @Sander_Mak
R
jshell
E
P
L
ead
val
rint
oop
Input code
Run code

31. @Sander_Mak
R
jshell
E
P
L
ead
val
rint
oop
Input code
Run code
See results

32. @Sander_Mak
R
jshell
E
P
L
ead
val
rint
oop
Input code
Run code
See results
Iteratively refine

33. @Sander_Mak
jshell
DEMO

34. @Sander_Mak
Collection Factory Methods

35. @Sander_Mak
List<String> books = new ArrayList<>();
books.add("Java 9 Modularity");
books.add("Designing Data-Intensive Applications");
books.add("Java 8 Lambdas");
Collection Factory Methods

36. @Sander_Mak
Collection Factory Methods
List<String> books = List.of("Java 9 Modularity",
"Designing Data-Intensive Applications",
"Java 8 Lambdas");

37. @Sander_Mak
Collection Factory Methods
List<String> books = List.of("Java 9 Modularity",
"Designing Data-Intensive Applications",
"Java 8 Lambdas");
Set.of Map.of

38. @Sander_Mak
Java
10
(March 2018)

39. @Sander_Mak
var

40. @Sander_Mak
var
String name = "Sander";

41. @Sander_Mak
var
String name = "Sander";
public void aMethod() {
String name = "Sander";
}

42. @Sander_Mak
var
String name = "Sander";
public void aMethod() {
String name = "Sander";
}
public void aMethod() {
var name = "Sander";
}

43. @Sander_Mak
var
URL url = new URL("https://javamodularity.com");
URLConnection connection = url.openConnection();
BufferedInputStream inputStream =
new BufferedInputStream(connection.getInputStream());

44. @Sander_Mak
var
URL url = new URL("https://javamodularity.com");
URLConnection connection = url.openConnection();
BufferedInputStream inputStream =
new BufferedInputStream(connection.getInputStream());
var bookurl = new URL("https://javamodularity.com");
var connection = bookurl.openConnection();
var bookStream = new BufferedInputStream(connection.getInputStream());

45. @Sander_Mak
var
URL url = new URL("https://javamodularity.com");
URLConnection connection = url.openConnection();
BufferedInputStream inputStream =
new BufferedInputStream(connection.getInputStream());
var bookurl = new URL("https://javamodularity.com");
var connection = bookurl.openConnection();
var bookStream = new BufferedInputStream(connection.getInputStream());

46. @Sander_Mak
var
URL url = new URL("https://javamodularity.com");
URLConnection connection = url.openConnection();
BufferedInputStream inputStream =
new BufferedInputStream(connection.getInputStream());
var bookurl = new URL("https://javamodularity.com");
var connection = bookurl.openConnection();
var bookStream = new BufferedInputStream(connection.getInputStream());
DEMO

47. @Sander_Mak
Java
11
(Sept. 2018)

48. @Sander_Mak
HttpClient
HttpURLConnection
HTTP/2 & WebSocket
Reactive Streams Support

49. @Sander_Mak
HttpClient
send
sendAsync
...
HttpClient

50. @Sander_Mak
HttpClient
send
sendAsync
...
HttpClient.Builder
newBuilder
HttpClient

51. @Sander_Mak
HttpClient
send
sendAsync
...
HttpClient.Builder
HttpRequest
uri
headers
method
...newBuilder
HttpClient

52. @Sander_Mak
HttpClient
send
sendAsync
...
HttpClient.Builder
HttpRequest
uri
headers
method
...
HttpRequest.Builder
newBuilder
newBuilder
HttpClient

53. @Sander_Mak
HttpClient
send
sendAsync
...
HttpClient.Builder
HttpRequest
uri
headers
method
...
HttpRequest.Builder
HttpResponse
uri
statusCode
body
...newBuilder
newBuilder
HttpClient

54. @Sander_Mak
HttpClient
HttpClient httpClient = HttpClient.newHttpClient();
HttpRequest req = HttpRequest.newBuilder(URI.create("https://google.com"))
.GET()
.build();
HttpResponse<String> response = httpClient.send(req, BodyHandlers.ofString())

55. @Sander_Mak
Java
12
(March 2019)

56. @Sander_Mak
Preview Feature: Switch Expression

57. @Sander_Mak
Preview Feature: Switch Expression
int numLetters = switch (day) {
case MONDAY, FRIDAY, SUNDAY -> 6;
case TUESDAY -> 7;
case THURSDAY, SATURDAY -> 8;
case WEDNESDAY -> 9;
};

58. @Sander_Mak
Let's Talk About Adoption

59. @Sander_Mak
https://jaxenter.com/java-8-still-strong-java-10-142642.html

60. @Sander_Mak
https://jaxenter.com/java-8-still-strong-java-10-142642.html
https://www.baeldung.com/java-in-2018

61. @Sander_Mak
https://jaxenter.com/java-8-still-strong-java-10-142642.html
https://www.baeldung.com/java-in-2018
https://www.jetbrains.com/research/devecosystem-2018/java/

62. @Sander_Mak
https://jaxenter.com/java-8-still-strong-java-10-142642.html
https://www.baeldung.com/java-in-2018
https://www.jetbrains.com/research/devecosystem-2018/java/
Java Magazine & Snyk

63. @Sander_Mak
https://jaxenter.com/java-8-still-strong-java-10-142642.html
https://www.baeldung.com/java-in-2018
https://www.jetbrains.com/research/devecosystem-2018/java/
Java Magazine & Snyk

64. @Sander_Mak
Java 11

65. @Sander_Mak
Java 11
Java 9
Java 10
Java 12
Java 13
6 months
Java 11

66. @Sander_Mak
Java 11
Java 9
Java 10
Java 12
Java 13
6 months
Java 11

67. @Sander_Mak
Java 11
Long
Term
Support
Java 9
Java 10
Java 12
Java 13
6 months
Java 11 Java 11 LTS
minimum 3 years

68. @Sander_Mak
Which JDK?
JDK 11 changes the game

69. Thanks. Read More:
javamodularity.com
@Sander_Mak
bit.ly/ps-sander