jchanghong.cache.CacheHelp.kt Maven / Gradle / Ivy
package jchanghong.cache
import cn.hutool.cron.CronUtil
import java.util.concurrent.ConcurrentHashMap
import java.util.function.Supplier
/** 后台定时更新cache，如果提供了 supplier,只能用get put方法*/
class CronMap(val cron:String):ConcurrentHashMap() {
// 调度id map
private val schedulerIdMap = ConcurrentHashMap()
private val supplierMap = ConcurrentHashMap>()
// put 为false，不调度，一旦调用过get。就调度
private val lateinitMap = ConcurrentHashMap()
init {
try {
CronUtil.setMatchSecond(true)
CronUtil.start()
} catch (e: Throwable) {
}
}
@Synchronized
@JvmOverloads
fun get2(key: K,supplier:Supplier? =null,cron: String?=null): V? {
if (supplier != null) {
supplierMap[key]=supplier
lateinitMap[key] = true
return getAndSchudulValue(supplier, key,cron)
}
return super.get(key)
}
private fun getAndSchudulValue(supplier: Supplier, key: K, cron: String?=null): V? {
schedulerIdMap[key]?.let { CronUtil.remove(it) }
val scheduleId = CronUtil.schedule(cron?:this.cron, Runnable {
if (lateinitMap[key] == true) {
val value = supplier.get()
this[key] = value
println("调度 已更新key $key -> $value" )
}
})
schedulerIdMap[key] = scheduleId
if (lateinitMap[key] == true) {
val value = supplier.get()
put(key, value)
return value
}
return null
}
@Synchronized
@JvmOverloads
fun put2(key: K, supplier:Supplier,cron: String?=null): V? {
supplierMap[key]=supplier
if (!lateinitMap.containsKey(key)) {
lateinitMap[key] = false
}
getAndSchudulValue(supplier, key, cron)
return null
}
@Synchronized
override fun get(key: K): V? {
lateinitMap[key]=true
val v = super.get(key)
if (v == null && supplierMap.containsKey(key)) {
val get = supplierMap[key]?.get()?.apply { put(key,this) }
return get
}
return v
}
}
object CacheHelp {
/**
* CronMap
*/
fun newCronMap(cron: String): CronMap {
return CronMap(cron)
}
}
fun main() {
val cache = CacheHelp.newCronMap( "1/5 * * * * ?")
cache.put2("test", Supplier { "sasa" })
println(cache.get("test"))
println(cache.get("test"))
Thread.sleep(2000)
println(cache.get("test"))
println(cache.get("test"))
}