Microservice: Introduction to Spring & Http

 -> equals() Contract

1. reflexive: an object must equal itself

2. symmetric: x.equals(y) must return the same result as y.equals(x)

3. transitive: if x.equals(y) and y.equals(z), then also x.equals(z)

4. consistent: the value of equals() should change only if a property that is contained in equals() changes (no randomness allowed)

-> hashCode() Contract

All three criteria in the hashCode() contract mention the equals() method in some way:

1. internal consistency: the value of hashCode() may only change if a property that is in equals() changes

2. equals consistency: objects that are equal to each other must return the same hashCode

3. collisions: unequal objects may have the same hashCode



Комментарии

Отправить комментарий

Популярные сообщения из этого блога

IoC:ApplicationContext, BeanFactory. Bean

 Bean - bean is an instance of a class managed by Spring Boot. In Spring Boot—and the broader Spring Framework—a bean is essentially an object that is managed by the Spring Inversion of Control (IoC) container. Beans are the backbone of a Spring application; they are the components that form the application and are responsible for performing its operations. Key Concepts: Inversion of Control (IoC): Instead of the application code controlling the flow of the program, control is inverted and given to the IoC container. This means the container is responsible for instantiating, configuring, and managing the lifecycle of beans. Dependency Injection (DI): This is a design pattern that allows an object (the client) to receive other objects it depends on (the services) from the IoC container, rather than creating them directly. Defining a Bean: In Spring Boot, you can declare beans in several ways: Using Annotations: @Component : A generic stereotype for any Spring-managed ...
Далее...

Lesson1: JDK, JVM, JRE

Изображение
1. Compiler - takes the entire programming code written in high language and translates the whole of it into machine code at once. After this process the an executable file will be ready to run. The translation takes some times to be done, but after that execution is so fast. 2. Interpreter - takes each single instructions of the code translates it and then executes it on its own. The translation step is before the program runs is fast, but execution is slow. JDK = JRE + development tools JRE = JVM + library class JDK -> Java Development Kit. A kit which provides the environment to develop and execute (run) Java program. JRE -> Java Runtime Environment. Provides environment to only run. JVM -> Java Virtual Machine f * Compiled: Fortran, C, C++, Pascal, Haskell, Rust, Go * Interpreted: JavaScript, PHP, Python, Ruby Java both compiled and interpreted language. Terminalda : javac Main.java yazdiqda, source fayli(.java) bytecode(.class) faylina cevirir. Terminalda: java Main (bu z...
Далее...

Lesson_2: Operations in Java

1. Capda toplama emeliyyatinin ferqi: package org.example.test ; public class Test { public static void main (String[] args) throws Exception { int one = 1 ; int two = 2 ; System. out .println( "result = " + one + two) ; System. out .println(one + two + " result" ) ; } }   char a = 'a' ; char b = 'b' ; System. out .println(a + b) ; System. out .println( 'a' + 'b' ) ; System. out .println( "" + a + b) ; System. out .println( "" + 'a' + 'b' ) ; 2. float ve double-da bash veren riyazi emaliyyat xeyalari: package org.example.test ; public class Test { public static void main (String[] args) throws Exception { float f = 0.6F ; System. out .println(f + 0.1 ) ; } } Operators in Java Operators in Java can be classified into 6 types: Arithmetic Operators Assignment Operators Relational Operators Logical Operators Unary Operators Bitwise Operator...
Далее...