如何在Go语言中使用Goroutines进行资源池管理

type Connection struct {
    // 数据库连接
    DB *sql.DB
    // 是否正在被使用
    InUse bool
    // 互斥锁
    Mutex sync.Mutex
}

type ResourcePool struct {
    // 最大连接数
    MaxConnections int
    // 当前使用的连接数
    CurrentConnections int
    // 资源池
    Pool []*Connection
    // 互斥锁
    Mutex sync.Mutex
    // 等待队列
    WaitQueue chan bool
}

func NewResourcePool(maxConnections int) *ResourcePool {
    pool := &ResourcePool{
        MaxConnections:     maxConnections,
        CurrentConnections: 0,
        Pool:               make([]*Connection, maxConnections),
        WaitQueue:          make(chan bool),
    }
    for i := 0; i < maxConnections; i++ {
        pool.Pool[i] = &Connection{}
    }
    return pool
}

func (pool *ResourcePool) Get() *Connection {
    // 加锁
    pool.Mutex.Lock()
    defer pool.Mutex.Unlock()

    // 检查连接池
    for i := 0; i < pool.MaxConnections; i++ {
        conn := pool.Pool[i]
        if !conn.InUse {
            // 找到可用的连接
            conn.Mutex.Lock()
            conn.InUse = true
            conn.Mutex.Unlock()

            pool.CurrentConnections++
            return conn
        }
    }

    // 进入等待队列
    pool.WaitQueue <- true
    return nil
}

func (pool *ResourcePool) Put(conn *Connection) {
    // 加锁
    conn.Mutex.Lock()
    conn.InUse = false
    conn.Mutex.Unlock()

    // 归还到资源池
    pool.Mutex.Lock()
    pool.CurrentConnections--
    pool.Mutex.Unlock()

    // 通知等待队列
    select {
    case <-pool.WaitQueue:
        // 有等待的Goroutine，唤醒一个
        pool.Mutex.Lock()
        pool.CurrentConnections++
        pool.Mutex.Unlock()

        pool.WaitQueue <- true
    default:
        // 没有等待的Goroutine
    }
}

func main() {
    pool := NewResourcePool(10)
    // 创建多个Goroutine并发获取数据库连接
    for i := 0; i < 20; i++ {
        go func() {
            conn := pool.Get()
            if conn != nil {
                // 使用数据库连接进行查询等操作
                fmt.Println("Do something with database connection")
                time.Sleep(time.Second * 3)

                // 使用完毕后归还连接到资源池
                pool.Put(conn)
            }
        }()
    }
    // 等待Goroutine执行完毕
    time.Sleep(time.Second * 20)
}