java-development-manual

Java Development Manual (Songshan Edition)

Overview

This manual is based on the Alibaba Java Development Manual (Songshan Edition), and divides the conventions into 7 dimensions. The conventions are divided according to the strength of their binding force into:

Level	Meaning	Description
[Mandatory]	Must be followed	Violation may cause serious problems
[Recommended]	Recommended to follow	Improves code quality and maintainability
[Reference]	May be optionally adopted	Judge according to the actual situation

Chapter Navigation

Select the detailed conventions of the corresponding chapter according to your needs:

Chapter	Applicable Scenarios	Detailed Documentation
Programming Conventions	Naming, formatting, OOP, concurrency, collection handling	coding-convention.md
Exception Logs	Error codes, exception handling, logging conventions	exception-log.md
Unit Testing	Test cases, coverage, Mock	unit-test.md
Security Conventions	SQL injection, XSS, CSRF, desensitization	security.md
MySQL Database	Table creation, indexes, SQL, ORM	mysql.md
Engineering Structure	Layered architecture, dependency management, servers	project-structure.md
Design Conventions	UML, design patterns, design principles	design.md

Quick Reference

Naming Convention Quick Reference

// 类名：UpperCamelCase
public class UserService { }
public class UserDO { }      // DO/DTO/VO例外

// 方法名/变量：lowerCamelCase
private String userName;
public void getUserById() { }

// 常量：全大写+下划线
public static final int MAX_RETRY_COUNT = 3;

// 包名：全小写
package com.company.project.service;

Prohibited Items Quick Reference

Prohibited	Reason
Pinyin naming	Poor readability
Magic values	Difficult to maintain
SELECT *	Performance and maintainability
Executors creating thread pools	Possible OOM
String concatenation SQL	Injection risk
return in finally	Loses try return value
remove in foreach	ConcurrentModificationException

Must-Do Items Quick Reference

Must	Reason
Add @Override to overridden methods	Avoid signature errors
Tables must have three fields	id, create_time, update_time
Desensitize sensitive data	Privacy protection
Parameter validation	Security protection
ThreadLocal cleanup	Avoid memory leaks
Use placeholders in logs	Performance optimization

Exception Handling Quick Reference

// 正确的异常处理
try {
    // 业务逻辑
} catch (SpecificException e) {
    logger.error("操作失败, 参数: {}", params, e);
    throw new BusinessException("用户友好提示", e);
} finally {
    // 资源关闭（JDK7+ try-with-resources）
}

Database Quick Reference

-- 建表必备
CREATE TABLE example (
    `id` bigint unsigned NOT NULL AUTO_INCREMENT,
    `create_time` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP,
    `update_time` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- 索引命名
-- 主键: pk_字段名
-- 唯一: uk_字段名
-- 普通: idx_字段名

Concurrency Handling Quick Reference

// 线程池创建
ThreadPoolExecutor executor = new ThreadPoolExecutor(
    corePoolSize,
    maximumPoolSize,
    keepAliveTime,
    TimeUnit.SECONDS,
    new LinkedBlockingQueue<>(queueCapacity),
    new ThreadFactory() {
        private AtomicInteger counter = new AtomicInteger(1);
        public Thread newThread(Runnable r) {
            return new Thread(r, "worker-" + counter.getAndIncrement());
        }
    },
    new ThreadPoolExecutor.CallerRunsPolicy()
);

// ThreadLocal使用
try {
    threadLocal.set(value);
    // 业务逻辑
} finally {
    threadLocal.remove();  // 必须回收
}

Usage Guide

Code Review Scenarios

1. Naming check → see coding-convention.md the "Naming Style" chapter
2. Concurrency issues → see coding-convention.md 's "Concurrent Processing" section
3. Exception Handling → View exception-log.md
4. Security Issues → View security.md

New Project Setup Scenario

1. Architecture Design → View design.md
2. Layered Structure → View project-structure.md
3. Database Design → View mysql.md
4. Unit Testing → View unit-test.md

Troubleshooting Scenario

1. NPE Issues → View exception-log.md 's "NPE Protection"
2. Performance Issues → View mysql.md 's "Index Guidelines"
3. Concurrency Issues → View coding-convention.md 's "Concurrent Processing"