Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Sign up for free
Menu
Search
Features
All features
Private URLs
Password Protection
Custom URLS
Scheduled publishing
Remove Branding
Restrict embedding
Deck Collections
Notes
Features
All features
Private URLs
Password Protection
Custom URLS
Scheduled publishing
Remove Branding
Restrict embedding
Deck Collections
Notes
Explore
Featured decks
Featured speakers
Programming
Technology
Storyboards
Explore
Featured decks
Featured speakers
Programming
Technology
Storyboards
Pricing
Search
Sign in
Sign up for free
Fundamental Java
Search
HASUNUMA Kenji
April 20, 2016
Programming
64
0
Share
Embed
Copy iframe code
Copy JS code
Copy link
Start on current slide
Fundamental Java
HASUNUMA Kenji
April 20, 2016
More Decks by HASUNUMA Kenji
See All by HASUNUMA Kenji
Jakarta EE: The First Parts
khasunuma
0
76
Life of our small product
khasunuma
0
54
How to adapt MicroProfile API for generic Web applications
khasunuma
0
57
Overviewing Admin Console
khasunuma
0
52
Introduction to MicroProfile Metrics
khasunuma
0
84
Basic method for Java EE Web Profile
khasunuma
0
55
Introduction to JCA and MDB
khasunuma
0
110
Collections Framework Begineers Guide 2
khasunuma
0
120
JLS myths ~ if-then-else statement ~
khasunuma
0
80
Other Decks in Programming
See All in Programming
設計次第でAIコードの読む量は減らせる / designing-for-code-reading
minodriven
35
17k
When benchmarks go bad - what I learned from measuring performance wrong
hollycummins
0
240
全ての永続トークンを、生まれる前に消し去りたい!
sylph01
2
1.3k
우리의 Nitro Modules는 당신의 Turbo Modules보다 아름답다
l2hyunwoo
0
220
當我們開始不讀 Code - AI Agent 時代,Code Review 與 Clean Code 還剩下什麼?
jame2408
1
320
Apple Intelligenceとオンデバイス時代の到来
yahir0
0
140
Domain-Driven Transformation
hschwentner
2
2.3k
graphql-ruby を Spinel で速くしようとした話
mtsmfm
0
120
Jetpack Compose Mechanisms
skydoves
3
870
Vapor Mode でアクセシビリティは 壊れないか検証した話
fuqda
1
120
作って学ぶSpring BootのAuto Configuration / JJUG Night Seminar 2026-10-19
rshindo
0
210
PumaからFalconに移行したRailsアプリケーションでの実践
falcon8823
0
230
Featured
See All Featured
The Power of CSS Pseudo Elements
geoffreycrofte
82
6.6k
SEOcharity - Dark patterns in SEO and UX: How to avoid them and build a more ethical web
sarafernandez
0
310
Building a A Zero-Code AI SEO Workflow
portentint
PRO
0
790
The AI Revolution Will Not Be Monopolized: How open-source beats economies of scale, even for LLMs
inesmontani
PRO
3
3.8k
Leveraging Curiosity to Care for An Aging Population
cassininazir
1
540
Lessons Learnt from Crawling 1000+ Websites
charlesmeaden
PRO
1
1.6k
Ten Tips & Tricks for a 🌱 transition
stuffmc
1
270
Digital Projects Gone Horribly Wrong (And the UX Pros Who Still Save the Day) - Dean Schuster
uxyall
1
3.5k
Impact Scores and Hybrid Strategies: The future of link building
tamaranovitovic
0
470
How to Grow Your eCommerce with AI & Automation
katarinadahlin
PRO
2
330
svc-hook: hooking system calls on ARM64 by binary rewriting
retrage
2
640
Hiding What from Whom? A Critical Review of the History of Programming languages for Music
tomoyanonymous
3
1.4k
Transcript
Fundamental Java HASUNUMA Kenji Vice president, GlassFish Users Group Japan
[email protected]
Twitter: @btnrouge
What’s Java?
Javaͷಛ • Φʔϓϯͳن֨Ͱ͋Δ • ৗʹਐԽ͍ͯ͠Δ • ޓੑΛॏࢹ͍ͯ͠Δ
JavaΦʔϓϯن֨ • ݴޠɺඪ४APIɺԾϚγϯ༷ • Java Community ProcessͰඪ४Խ • ݱࡏΦʔϓϯιʔε (GPLv2)
wWrite Once, Run Anywhere wݴޠϨϕϧͰϚϧνεϨουରԠ wݫ֨ͳྫ֎ॲཧػߏ w6OJDPEFΛશ໘తʹ࠾༻
Write Once, Run Anywhere • OSɺJava VM࣮ʹґଘ͠ͳ͍ • ݹ͍ίʔυ͕࠷৽ͷJavaͰಈ͘ •
Blu-ray͔ΒڊେγεςϜ·Ͱ
ॳ04ͷࠩҟΛ+BWB7.͕ٵऩ͢Δ ݱࡏ+BWB7.͕ଟݴޠͷڞ௨ج൫
Essential Java
JavaͷΤίγεςϜ
ΫϥεͱΠϯλϑΣʔε
!
! Ϋϥεͷܧঝ
" #
" Polymorphismͱ
$%& '&( ( )&%%%
ϓϩηεͱεϨου
$%& '&( ( )&%%%
$%* $%* $%* + + ϓϩηεͱεϨου
, "- # ./0 , 0 #- ./0 " " " " " " -""1 +BWBͷೖग़ྗ 4USFBN ݱࡏͰจࣈྻσʔλʹಛԽͨ͠3FBEFS8SJUFSɺ ߴ*0Λ࣮ݱ͢Δ$IBOOFMΑ͘ΘΕ͍ͯΔ
+BWBͷύοέʔδ
Ϋϥε໊ͷදهํ๏ wݪଇύοέʔδΛؚΉશ໊ ྫ java.util.List wimportએݴಛఆͷύοέʔδΛলུՄ ํ๏ import java.util.List; ํ๏ import
java.util.*; wjava.langʜৗʹύοέʔδΛলུՄ
+BWBΫϥεͷಉҰੑ • Ϋϥε໊͕ಉҰͰ͋Δ • ύοέʔδ໊͕શʹҰக͍ͯ͠Δ • ಉ͡Ϋϥεϩʔμʔ͔ΒಡΈࠐ·Εͨ
Java Core Parts
ΫϥεͱΦϒδΣΫτ • ΫϥεఆٛͷΈ…࣮ମ͕ͳ͍ • ΦϒδΣΫτ(Πϯελϯε) …Ϋϥε͔Β࡞࣮ͨ͠ମͷ͜ͱ • ϑΟʔϧυͱϝιουΦϒδΣΫτʹ ଐ͢Δ(㱻staticΫϥεʹଐ͢Δ)
java.lang.Object • JavaͷશΫϥεͷεʔύʔΫϥε • ΫϥεͷࠜװʹؔΘΔϝιουΛ࣋ͭ • ϓϦϛςΟϒܕʹରͯ͠ϦϑΝϨϯεܕ ͱݺΕΔ͜ͱ͋Δ
java.lang.Object ͷϝιου equals ಉҰνΣοΫʹ͏ ※ݪଇͱͯ͠ΦʔόʔϥΠυ͢Δ hashCode toString จࣈྻදݱΛฦ͢ ※༻్༷ʑ wait
εϨου੍ޚ༻ϝιου ※௨ৗConcurrency UtilitiesΛܦ༝ ͯ͠༻͢Δ(ΦʔόʔϥΠυෆՄ) notify notifyAll clone ίϐʔ(࠷ۙΘΕͳ͍) finalize ޙॲཧ(௨ৗΦʔόʔϥΠυ͠ͳ͍)
Object o = new Object();
Object o = new Object();
Object o = new Object(); ӈลͱಉ͡Ϋϥε PS εʔύʔΫϥε PS ࣮ΠϯλϑΣʔε
Object o = new ArrayList();
Ωϟετ Object o = new ArrayList(); • objͷఆٛObjectɺ࣮ମArrayList • ΞΫηεఆٛΛ௨ͯ͡ߦ͏
• ࣮ମͷΞΫηεˠΩϟετ ArrayList list = (ArrayList) o; w Ωϟετ=αϒΫϥεͷఆٛͰΞΫηε w Ωϟετޙ࣮ମʹΞΫηεՄೳ
ϓϦϛςΟϒܕ • ΫϥεͰͳ͍σʔλܕ • ରԠ͢ΔΫϥε(ϥούʔ)Λ࣋ͭ • auto-boxing/unboxing: ϓϦϛςΟϒܕͱϥούʔͷ૬ޓม
ϓϦϛςΟϒܕ ϥούʔΫϥε boolean Boolean byte Byte char Character short Short
int Integer long Long float Float double Double
ྻ • ಉ͡ΫϥεorϓϦϛςΟϒܕͷ࿈ଓ • ԋࢉࢠ [ ] ͰཁૉʹΞΫηε͢Δ • ෦తʹjava.lang.ArrayΫϥε
Object[ ] o = new Object[8]; P0CKFDUͷྻ ཁૉࢦఆ͠ͳ͍ ྻͷཁૉ ඞͣఆޙͰมߋෆՄ
ྻͷ߹ɺࠨลͱӈลಉ͡Ϋϥε
ͦͷଞͷॏཁͳτϐοΫ • Generics (J2SE 5.0) • Annotation (J2SE 5.0) •
Project Coin (Java SE 7) • Collections Framework (J2SE 1.2) • New I/O (J2SE 1.4 & Java SE 7) • Concurrency Utilitites (J2SE 5.0 & Java SE 7)
Fundamental Java HASUNUMA Kenji
[email protected]
Twitter: @btnrouge