The document outlines various features and enhancements introduced in Java versions 9 to 13, including text blocks, switch expressions, and HTTP client capabilities. It also discusses the modularity in Java introduced in JDK 9, the impact on legacy codebases, and considerations for Java adoption and long-term support. The presentation encourages developers to leverage the new functionalities for improved application architecture and maintainability.

1. Coding Your Way to
Java 13
@Sander_Mak

2. About Sander
Director of Technology
@ Picnic
Conference Speaker & Author

3. @Sander_Mak
Java
13
(Sept. 2017)

4. @Sander_Mak
Preview Feature: Text Blocks
String jsonOrIsIt = "{n" +
" "no": "escaping for nested strings!",n" +
" "preserves_indentation?": true,n" +
" "awesomeness_level": 11n" +
"}";

5. @Sander_Mak
Preview Feature: Text Blocks
String json = """
{
"no": "escaping for nested strings!",
"preserves_indentation?": true,
"awesomeness_level": 11
}""";

6. @Sander_Mak
Java
12
(March 2019)

7. @Sander_Mak
Switch
Statements
int numletters;
switch (day) {
case MONDAY:
FRIDAY:
SUNDAY: numletters = 6;
break;
case TUESDAY: numletters = 7;
break;
case THURSDAY:
SATURDAY: numletters = 8;
break;
case WEDNESDAY: numletters = 9;
break;
}

8. @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;
};

9. @Sander_Mak
Java
11
(Sept. 2018)

10. @Sander_Mak
HttpClient
HttpURLConnection

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

12. @Sander_Mak
HttpClient
send
sendAsync
...
HttpClient

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

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

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

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

17. @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())

18. @Sander_Mak
Java

19. @Sander_Mak
Java
9
(Sept. 2017)

20. @Sander_Mak
R
jshell
E
P
L

21. @Sander_Mak
R
jshell
E
P
L
ead

22. @Sander_Mak
R
jshell
E
P
L
ead
val

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

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

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

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

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

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

29. @Sander_Mak
jshell
DEMO

30. @Sander_Mak
Java
10
(March 2018)

31. @Sander_Mak
var

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

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

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

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

36. @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());

37. @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());

38. @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

39. @Sander_Mak
Java
9
(Sept. 2017)

40. @Sander_Mak
Collection Factory Methods

41. @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

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

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

44. @Sander_Mak
Quick Java Module Overview

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

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

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

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

49. @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

50. @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

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

52. @Sander_Mak
Why?

53. @Sander_Mak
Why?
Modular JDK

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

55. @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

56. @Sander_Mak
jlink

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

58. @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

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

60. @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

61. @Sander_Mak
Impact on Java 8 codebases

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

63. @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

64. @Sander_Mak
Let's Talk About Adoption

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

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

67. @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/

68. @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

69. @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

70. @Sander_Mak
Java 11

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

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

73. @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

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

75. @Sander_Mak
Oracle JDK 8
Binary Code License

76. @Sander_Mak
Oracle JDK 8
Binary Code License
Oracle JDK 11
Java SE Subscription
$

77. @Sander_Mak
Oracle JDK 8
Binary Code License
Oracle JDK 11
Java SE Subscription
$
OpenJDK 11
GPL v2

78. @Sander_Mak
Oracle JDK 8
Binary Code License
Oracle JDK 11
Java SE Subscription
$
OpenJDK 11
GPL v2
=

79. @Sander_Mak
Oracle JDK 8
Binary Code License
Oracle JDK 11
Java SE Subscription
$
OpenJDK 11
GPL v2
Amazon Corretto
AdoptOpenJDK
Red Hat OpenJDK
Azul Zulu
=

80. Thanks. Join us:
join.picnic.app
@Sander_Mak
bit.ly/ps-sander