ویدئوهای توصیفی جاوا اسپرینگ بوت
فیلم های توصیفی زیر از پروژه ها ی جاوا اسپرینگ بوت استفاده می کنند تا مثال ها را نشان دهند. یکی از اصلی ترین پروژه ها، پروژه ی زیر هست که به صورت فایل زیپ قابل دانلود است و قابل تطبیق با توضیحات است.
Video 1 — ویدئوی اول
About Java Spring Boot using an interface
Overview:
– create Controller, include URLs including REST endpoints
using @GetMapping, @PostMapping, @DeleteMapping, @PutMapping
– creat right packages
(common ones are entity, repository, service, controller)
– create an interface
(in this application we have 3 interfaces
one for database interactions,
one for booking, and one for booking service)
interface includes the name and type of methods
you will implement in a class
Video 2 — ویدئوی دوم
Spring CRUD and SQL interactions
Overview:
CrudRepository: Simplification of Create-Read-Update-Delete interactions
<S extends T> save(S entity) – Used to save a single entity at a time.
Iterable<S> saveAll(Iterable<S> entities) – we can save multiple entities at a time.
Optional<T> findById(ID id) – use to get entity basis of id.
boolean existsById(ID id) – used to check whether an entity is already exited in DB for given Id.
Iterable<T> findAll() – find all entity of paricular type.
Iterable<T> findAllById(Iterable<ID> ids) – return all entity of given ids.
long count() – returns the number of entities
void deleteById(ID id) – delete the entity on basis of id
void delete(T entity) – delete the entity which one we are passing.
void delete(Iterable<? extends T> entities) – delete multiple entities which we are passing.
void deleteAll() – delete all entities.
(source: https://www.netsurfingzone.com/jpa/crudrepository-methods-example/ )
@Repository
@Transactional(readOnly = true)
enabling update and insert
@Modifying (see the class TaskStatusRepository.java)
Video 3 — ویدئوی سوم
Database Tables And The Respective Entities In Java Spring Boot
Overview:
We create a database table and define its columns as variables in the entity
Entities represent database tables
These are entities that we have in our Java Spring Boot application.
They will have services and repositoies associated with them.
A set of annotations clarify the class, including Lombok annotations.
The @Entity annotation is important
The @Table(name=”tablename”) is an example of an annotation to give
tablename.
The @Id annotation defines the id field
The @GeneratedValue annotation may be applied to a primary key property
We can define the relationship between tables using
@ManyToOne, @OneToMany, and @ManyToMany annotations.
Video 4 — ویدئوی چهارم
One To Many relation description
Overview:
– ٍExample: Task and TaskStatus. One task, many task statuses
– See in the database the foreign key relation
available in TaskStatus table
Example:
– Task.java
@OneToMany(mappedBy = “task”, cascade = CascadeType.ALL)
private Set<TaskStatus> taskStatuses;
– TaskStatus.java
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = “task_id”)
private Task task;
CascadeType
cascade = CascadeType.ALL
https://www.baeldung.com/jpa-cascade-types
FetchType
fetch = FetchType.LAZY
https://www.baeldung.com/hibernate-lazy-eager-loading
Video 5 — ویدئوی پنجم
Many To Many relation description
Overview:
– ٍExample: Task and Person.
One task, many persons
One person, many tasks
– join table is the name of the two tables concatenated with _
– person side is owning side. has @JoinTable annotation
– https://stackoverflow.com/questions/36803306/should-jointable-be-specified-in-both-sides-of-a-manytomany-relationship
– should add on owning side
Video 6 — ویدئوی ششم
Thymeleaf basics
Overview:
– Java EE templating possible with JSP, JSF (used to be in focus)
– Templating is a focus with Java EE, Java Spring Boot
– Thymeleaf: reviewing: https://www.thymeleaf.org/doc/tutorials/3.0/usingthymeleaf.html
– the generalities in an application:
<html xmlns:th=”http://www.thymeleaf.org”>
<p th:text=”#{home.welcome}”>Welcome to our grocery store!</p>
– fragments, variables, iterations, if statements, html tag values
– have fragments
fragment:
<div th:fragment=”adminDetailBar”…
use it:
<div th:insert=”fragments/general.html :: adminDetailBar” >This was admin bar</div>
<div th:replace=”fragments/header.html :: header-css”/>
th:insert is the simplest: it will simply insert the specified fragment as the body of its host tag.
th:replace actually replaces its host tag with the specified fragment.
th:include is similar to th:insert, but instead of inserting the fragment it only inserts the contents of this fragment.
– if-statements
<div th:if=”${user.isAdmin()} == false”> …
– variables
th:text=”${message}
@{${baseURL} + ‘/admin’}
– iteration
<tr class=”dataRow” th:each=”iter : ${worksuggests}”>
<td th:text=”${iter.worksuggest_id}”>id</td>
<td><a th:href=”@{${baseURL} + ‘/admin/worksuggestlist/’ + ${iter.worksuggest_id} + ‘/remove/’ }”
– switch statements
<div th:switch=”${user.role}”>
<p th:case=”‘admin'”>User is an administrator</p>
<p th:case=”#{roles.manager}”>User is a manager</p>
</div>
– th:value, th:text, … (see section 5.2 Setting value to specific attributes)
<select name=”worksuggestlistid”>
<option value=”” text=”Select the Work Suggestion List for this task” selected=”selected”></option>
<option th:each=”iter : ${worksuggests}”
th:value=”${iter.worksuggest_id}”
th:text=”${iter.title}”></option>
</select>
Video 7 — ویدئوی هفتم
Description for several parts of Spring Boot Security
Overview:
pom.xml file
dependencies
Spring Security is a Spring Framework feature
error handler implements AccessDeniedHandler
UserDetailsService features among others
User, UserDetails
AuthenticationSuccessHandler
WebSecurityConfigurerAdapter
Video 8 — ویدئوی هشتم
Spring Boot Security with basic DataSource
Overview:
Spring Boot makes Java app development easy for the web
A set of jar files — dependencies
test dependecies, application server dependecy (usually minimized in Spring Boot), usual dep.
here: mysql dependency, spring-boot-starter-security, //spring boot starter data jpa
a series of useful classes as autowires
ConfigureAuthentication
configure (WebSecurity web)
configure (HttpSecurity http)
configureGlobal
NoOpPasswordEncoder — various password encoders
now to log-in there will be credential check that comes from db
application.properties has db detail
which tables? authorities, users;
let’s see the database
see users…
log in
example tutorials. keywords: jdbc authentication in Spring Boot
Video 9 — ویدئوی نهم
Spring Boot Session with Redis
Overview:
– Session: keeping user detail while user interacts with our application
– set redis as datasource via application.properties
– download Redis, start its server otherwise Spring Boot can’t connect
– See Redis folder structure
– start redis-server.exe
redis-server.exe –maxheap 1024M
– start redis CLI
http://localhost:3306/
http://localhost:6379/
http://localhost:8080/
JavaInUse example
HttpSession variable as argument in main URL
session.getAttribute
HttpServletRequest
in persistMessage URL
request.getSession.setAttribute
also in URL for destroying the session
demo and the controller
http://localhost:8080/package1_war_exploded/
Video 10 — ویدئوی دهم
using BCrypt in Spring Boot
Overview:
============== SpringSecurityConfig file ============
SpringSecurityConfig has a configure method that takes in auth with the class
AuthenticationManagerBuilder.
It sets the auth’s authenticationProvider to use authProvider
authProvider itself is a bean of type DaoAuthenitcationProvider.
The bean authProvider is of type DaoAuthenticationProvider which is using the passwordEncoder.
It also uses a UserDetailsService
PasswordEncoder is set in the SpringSecurityConfig. It is set to return BCryptPasswordEncoder
PasswordEncoder is autowired in UsersService
User Service:
We can work with User Service which has several User interaction methods.
One of these is “saveUser”. Here in this method we can save our userpasswords with the password encoder
if we include it in our User Service class ile.
saveUser in UsersService uses the passwordEncoder (throught Autowire) to encode and set the password
User Entity:
Users entities has username, password, enabled.
whereever we need to interact with the user such as in UserService’s saveUsers we save with encyrption
for reading the password we just pass in password as is in database
in the user builder in userDetailsServiceImpl
=========== userDetailsServiceImpl ============
builder is spring based. Therefore its password field works with the encrypted password that we pass in
we are returning userDetailsService implementation as an autowire that works in
the SpringSecurityConfig and the DaoAuthenticationProvider.
Video 11 — ویدئوی یازدهم
Spring Boot Angular app description
Overview:
Angular – Interactions: drag and drop
Spring Boot:
Entities: database table structures
Repositories: interactions with the database
Services: contact between (interactions with database) and the user requests (controller)
returning JSON format results
demo of RESTpoints
