Go Map 并发安全性：理解与实践

package main

import (
    "fmt"
    "sync"
    "time"
)

// SafeMap 是一个并发安全的 map 包装
type SafeMap struct {
    mu   sync.RWMutex
    data map[string]interface{}
}

// NewSafeMap 创建一个新的 SafeMap
func NewSafeMap() *SafeMap {
    return &SafeMap{
        data: make(map[string]interface{}),
    }
}

// Store 设置键值对
func (sm *SafeMap) Store(key string, value interface{}) {
    sm.mu.Lock() // 写操作加写锁
    defer sm.mu.Unlock()
    sm.data[key] = value
}

// Load 获取键对应的值
func (sm *SafeMap) Load(key string) (interface{}, bool) {
    sm.mu.RLock() // 读操作加读锁
    defer sm.mu.RUnlock()
    val, ok := sm.data[key]
    return val, ok
}

// Delete 删除键值对
func (sm *SafeMap) Delete(key string) {
    sm.mu.Lock() // 写操作加写锁
    defer sm.mu.Unlock()
    delete(sm.data, key)
}

func main() {
    safeMap := NewSafeMap()
    var wg sync.WaitGroup

    // 多个 Goroutine 并发写入
    for i := 0; i < 100; i++ {
        wg.Add(1)
        go func(i int) {
            defer wg.Done()
            key := fmt.Sprintf("key-%d", i)
            value := fmt.Sprintf("value-%d", i)
            safeMap.Store(key, value)
            // fmt.Printf("写入: %s -> %s\n", key, value) // 打印过多可能影响观察
        }(i)
    }

    // 多个 Goroutine 并发读取
    for i := 0; i < 50; i++ {
        wg.Add(1)
        go func(i int) {
            defer wg.Done()
            key := fmt.Sprintf("key-%d", i*2) // 读一些可能已写入的键
            val, ok := safeMap.Load(key)
            if ok {
                // fmt.Printf("读取: %s -> %v\n",