MrSnyder

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;

public class BootstrapGridifier {

	public static void main(String[] args) throws IOException {

MrSnyder

Spring Security Cheatsheet

HttpSecurity

	@Override
	protected void configure(HttpSecurity http) throws Exception {
	    http
	        .authorizeRequests()
 .antMatchers("/", "/images/**", "/styles.css", "/webjars/**").permitAll()

MrSnyder

Markdown Cheatsheet

Level 2

A level 2 section

Level 3

A level 3 section

MrSnyder

Thymeleaf Cheatsheet

Fragments

https://www.baeldung.com/spring-thymeleaf-fragments

MrSnyder

Live-Coding Cheatsheet

Image-Handling JPA+Upload

• Explain ImageController
• Move #loadImage from ImageController to BookController
• Book entity: add LOB field
• Insert example via LOAD_FILE
• book/edit.html: Add input to form + change to multipart
• Controller anpassen (loadImage)

MrSnyder

Common Java naming rules

Casing variants

Example: Several individual words

• Upper camel case: SeveralIndividualWords
• Lower camel case: severalIndividualWords
• Snake case: Several_individual_words

Classes / Interfaces

• Examples
  • Book
• ImageUploadController

MrSnyder

JPA Cheatsheet

Minimal entity class mapping

Steps

• Required: Annotate class with @Entity
• Required: Define field with @Id annotation
• NOTE: Prefer Lombok for automatic Getter/Setter generation.

MrSnyder

Data Modelling Cheatsheet

Identifying relations

A relation between two tables A and B where a foreign key of A is (part of) the primary key of B.

CREATE TABLE AuthoredBook (
  author_id INT NOT NULL,
 book_id INT NOT NULL,

MrSnyder

Android Cheatsheet

Training material

• Codelabs for Android Developer Fundamentals
• Note taking app

Glossary

Official Vocabulary Glossary

MrSnyder

Java Cheatsheet

• Jenkov Tutorials

Inner, anonymous classes and lambdas

import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;