java-development-manual

Java Development Manual (Songshan Edition)

Overview

This manual is based on the Alibaba Java Development Manual (Songshan Edition), and divides the specifications into 7 dimensions. The specifications are divided by strength of constraint 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 specifications of the corresponding chapter according to your needs:

Chapter	Applicable Scenarios	Detailed Documentation
Programming Specifications	Naming, formatting, OOP, concurrency, collection handling	coding-convention.md
Exception Logs	Error codes, exception handling, logging specifications	exception-log.md
Unit Testing	Test cases, coverage, Mock	unit-test.md
Security Specifications	SQL injection, XSS, CSRF, masking	security.md
MySQL Database	Table creation, indexes, SQL, ORM	mysql.md
Engineering Structure	Layered architecture, dependency management, servers	project-structure.md
Design Specifications	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	May cause OOM
String concatenation SQL	Injection risk
return in finally	Loses the try return value
remove in foreach	ConcurrentModificationException

Mandatory Items Quick Reference

Mandatory	Reason
Add @Override to overridden methods	Avoid signature errors
Tables must have three fields	id, create_time, update_time
Mask 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 in the "Naming Style" chapter
2. Concurrency Issues → See coding-convention.md 's "Concurrency Handling" 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 "Concurrency Handling"