employee/IdGenerator.java

/**
 * ID生成器工具类
 * 提供生成唯一ID的功能
 * 遵循单例设计模式
 */
package com.employeetraining.util;

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.concurrent.atomic.AtomicLong;

public class IdGenerator {
    // 单例实例
    private static final IdGenerator instance = new IdGenerator();
    
    // 原子计数器，确保线程安全
    private final AtomicLong counter = new AtomicLong(0);
    
    // 日期时间格式化器
    private final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyyMMddHHmmss");
    
    // 私有构造函数，防止外部实例化
    private IdGenerator() {
    }
    
    /**
     * 获取单例实例
     */
    public static IdGenerator getInstance() {
        return instance;
    }
    
    /**
     * 生成唯一ID
     */
    public String generateId(String prefix) {
        String timestamp = LocalDateTime.now().format(formatter);
        long sequence = counter.incrementAndGet();
        return prefix + "-" + timestamp + "-" + sequence;
    }
    
    /**
     * 生成员工ID
     */
    public String generateEmployeeId() {
        return generateId("EMP");
    }
    
    /**
     * 生成课程ID
     */
    public String generateCourseId() {
        return generateId("CSE");
    }
    
    /**
     * 生成培训记录ID
     */
    public String generateTrainingRecordId() {
        return generateId("TRN");
    }
    
    /**
     * 生成证书ID
     */
    public String generateCertificateId() {
        return generateId("CRT");
    }
}