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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
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:
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Android SDK
android.app.Activity
200+ methods
it’s a shame
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time to change sides!
