Java vs OOP

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Java vs OOP

Yegor Bugayenko

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long video showing Clojure 8000+ lines Java

class

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Javabooks

frameworks

Google

OOP

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if it works, it’s good

if it’s good, it works

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“Just make $1B with something instead of ORM and you will be right”

— Victor

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enemy #1:

books

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“Objects may contain data, in the form of fields, often known as attributes; and code, in the form of procedures, often known as methods”

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“Each object looks quite a bit like a little computer — it has a state, and it has operations that you can ask it to perform” - page 16

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“A class is a collection of data fields that hold values and methods that operate on those values” - page 98

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“An object is some memory that holds a value of some type” - page 40

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“An object consists of some private memory and a set of operations.” - page 6

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“An object is the equivalent of the quanta from which the universe is constructed” - page 66

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enemy #2:

languages

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static

publicnull

final

return

instanceof

.class

@

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- immutability - setters - anemic model - data structures - procedural thinking

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static

- utility classes - singletons - procedural thinking

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instanceof

- reflection API - no polymorphism - no encapsulation - procedural thinking

.class

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@

- split objects apart - anemic model - procedural thinking

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enemy #3:

frameworks

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JAX-RSJPAPlay

Spring

JavaBeans

Apache Commons

Guava

JDK JAXB

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JAX-RS

@Path(“/”) public class Index { @GET @Produces(“text/plain”) public String get() { return “hello, world!”; } }

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Apache Commons

text = FileUtils.readFileToSTring(f); StringUtils.abbreviate(“hello, world!”); DigestUtils.md5(“some text”);

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JPA

@Entity(table = “book”) public class Book { @Id public int id; @Column public String title; }

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enemy #4:

Google

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Android SDK

android.app.Activity

200+ methods

it’s a shame

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time to change sides!

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$20

for JavaDay

[email protected]