Full-Stack Java Backend Engineer Knowledge Catalog

Block 1. Programming & Runtime Foundation

Foundation of all backend development.

1.1 Programming Basics

variables
data types
operators
conditionals
loops
methods/functions

1.2 Object-Oriented Programming (OOP)

class/object
encapsulation
inheritance
polymorphism
abstraction
interface
abstract class

1.3 Java Core

String
collections
generic
enum
exception
IO/NIO
reflection
annotation

1.4 JVM

JVM structure
heap / stack
GC
class loading
memory leak
OOM

1.5 Multithreading

thread
thread lifecycle
synchronized
Lock
volatile
CAS
thread safety

1.6 Concurrent Utilities

ThreadPoolExecutor
Future
CompletableFuture
CountDownLatch
Semaphore

1.7 Sync vs Async

synchronous
asynchronous
blocking
non-blocking

1.8 High Concurrency Basics

QPS/TPS
throughput
latency
bottleneck
traffic spike

Block 2. Spring / Framework Core

Core backend framework understanding.

2.1 What is Framework

framework vs library
inversion of control

2.2 Spring Core

Spring
Spring Boot
auto configuration
starter

2.3 IoC / DI

bean
container
BeanFactory
ApplicationContext
@Component
@Service
@Repository
@Controller
@Autowired
@Resource

2.4 AOP

proxy
dynamic proxy
CGLIB
aspect
advice
pointcut

2.5 Spring Lifecycle

bean lifecycle
initialization
circular dependency

2.6 Spring Boot Startup

@SpringBootApplication
auto scan
starter loading
configuration loading

Block 3. Web & API Layer

Request processing layer.

3.1 HTTP Basics

request/response
method
header
cookie
session
status code

3.2 MVC

MVC architecture
Spring MVC
DispatcherServlet

3.3 Request Flow

request lifecycle
controller mapping
parameter binding

3.4 Controller

@RestController
@RequestMapping
@GetMapping
@PostMapping
@PathVariable
@RequestParam
@RequestBody

3.5 Validation

@Valid
@NotNull
@NotBlank
global exception handling

3.6 Filter / Interceptor

Filter
Interceptor
login check
permission check
request logging

3.7 API Design

RESTful API
pagination
response wrapper
API versioning

Block 4. Business Logic & Domain

Most important real-world coding block.

4.1 Service Layer

business logic
service orchestration
domain thinking

4.2 Transaction

ACID
transaction isolation
@Transactional
rollback
propagation

4.3 State Management

state transition
order status
coupon lifecycle

4.4 Idempotency

repeated request
duplicate callback
token/idempotency key
unique constraint

4.5 Business Flow

payment flow
refund flow
coupon claim flow

4.6 Read & Debug Code

trace request flow
debug business logic
find root cause

4.7 Design Patterns

strategy
factory
template method
chain of responsibility

Block 5. Data & Persistence

Data storage and query layer.

5.1 Database Basics

relational database
table
PK/FK
normalization

5.2 SQL

CRUD
join
group by
index
execution plan

5.3 MySQL

transaction
lock
MVCC
slow query

5.4 ORM / Persistence

MyBatis
mapper
XML mapping
dynamic SQL

5.5 Persistence Annotation

@Table
@Column
@Id

5.6 Redis

cache
TTL
distributed lock
atomic operation

5.7 Data Consistency

cache consistency
DB consistency

Block 6. Concurrency, Async & Distributed

High-traffic backend systems.

6.1 High Concurrency

oversell
hot key
hotspot data
high traffic protection

6.2 Locking

optimistic lock
pessimistic lock
distributed lock

6.3 Async

async processing
async task
callback

6.4 MQ

Kafka
RabbitMQ
producer/consumer
retry
dead letter queue

6.5 Distributed System

distributed transaction
eventual consistency
CAP
service split

6.6 Resilience

retry
timeout
circuit breaker
rate limiting

6.7 Real Scenarios

flash sale
payment callback
inventory deduction
coupon claim

Block 7. Infrastructure & Operations

Deployment + production environment.

7.1 Linux

file system
process
permission
command line

7.2 Shell

bash
shell script

7.3 SSH

remote login
key pair

7.4 Docker

image
container
Dockerfile
docker-compose

7.5 Nginx

reverse proxy
load balancing
static resource

7.6 Deployment

jar deployment
CI/CD basics

7.7 Logs & Monitoring

logback
server log
tracing
metrics

7.8 Performance Tuning

JVM tuning
DB tuning
thread pool tuning

Block 8. Frontend & Full-Stack Interaction

Frontend-backend collaboration.

8.1 JavaScript

ES6
async/await
Promise

8.2 TypeScript

type system
interface
generic

8.3 Vue

component
props
lifecycle
routing

8.4 Frontend Request

axios
fetch

8.5 Frontend-Backend Interaction

token
CORS
API integration

8.6 UI Framework

layui
element-ui

8.7 SSR

server-side rendering basics

Block 9. System Design & Performance

Architecture thinking.

9.1 Architecture

layered architecture
microservice
modular design

9.2 Scalability

horizontal scaling
load balancing

9.3 Cache Design

cache strategy
cache consistency

9.4 Performance Optimization

DB optimization
API optimization
JVM optimization

9.5 Distributed Architecture

gateway
service registry
config center

9.6 Real System Design

flash sale system
payment system
coupon system
order system

Block 10. AI Usage & AI-Enhanced Development

AI-assisted engineering.

10.1 AI Coding Tools

ChatGPT
Cursor
Copilot

10.2 Prompt Engineering

precise prompting
debugging prompts
architecture prompts

10.3 AI-Assisted Debugging

log analysis
stacktrace analysis

10.4 AI API Integration

OpenAI API
streaming response
tool calling

10.5 RAG Basics

embedding
vector DB
retrieval

10.6 AI Product Backend

AI chat backend
session memory
prompt storage

10.7 AI + Backend Engineering

AI-generated CRUD
AI-assisted refactor
AI code review
AI workflow automation

MOST IMPORTANT RELATIONSHIP

Block 1 = language/runtime
Block 2 = framework
Block 3 = web request layer
Block 4 = business logic
Block 5 = data layer
Block 6 = high concurrency/distributed
Block 7 = deployment/operations
Block 8 = frontend interaction
Block 9 = architecture/system design
Block 10 = AI-enhanced engineering

summary