From 6bc01f6552c6bf523b9af668bbe8406e4255a82f Mon Sep 17 00:00:00 2001
From: usbharu <64310155+usbharu@users.noreply.github.com>
Date: Thu, 20 Apr 2023 22:02:14 +0900
Subject: [PATCH] =?UTF-8?q?feat:=20ID=E7=94=9F=E6=88=90=E5=99=A8=E3=82=92?=
 =?UTF-8?q?=E8=BF=BD=E5=8A=A0?=
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---
 .../hideout/service/IdGenerateService.kt      |  5 ++
 .../service/SnowflakeIdGenerateService.kt     | 47 +++++++++++++++++++
 .../TwitterSnowflakeIdGenerateService.kt      |  4 ++
 .../TwitterSnowflakeIdGenerateServiceTest.kt  | 35 ++++++++++++++
 4 files changed, 91 insertions(+)
 create mode 100644 src/main/kotlin/dev/usbharu/hideout/service/IdGenerateService.kt
 create mode 100644 src/main/kotlin/dev/usbharu/hideout/service/SnowflakeIdGenerateService.kt
 create mode 100644 src/main/kotlin/dev/usbharu/hideout/service/TwitterSnowflakeIdGenerateService.kt
 create mode 100644 src/test/kotlin/dev/usbharu/hideout/service/TwitterSnowflakeIdGenerateServiceTest.kt

diff --git a/src/main/kotlin/dev/usbharu/hideout/service/IdGenerateService.kt b/src/main/kotlin/dev/usbharu/hideout/service/IdGenerateService.kt
new file mode 100644
index 00000000..8a74d9e4
--- /dev/null
+++ b/src/main/kotlin/dev/usbharu/hideout/service/IdGenerateService.kt
@@ -0,0 +1,5 @@
+package dev.usbharu.hideout.service
+
+interface IdGenerateService {
+    suspend fun generateId():Long
+}
diff --git a/src/main/kotlin/dev/usbharu/hideout/service/SnowflakeIdGenerateService.kt b/src/main/kotlin/dev/usbharu/hideout/service/SnowflakeIdGenerateService.kt
new file mode 100644
index 00000000..69cda875
--- /dev/null
+++ b/src/main/kotlin/dev/usbharu/hideout/service/SnowflakeIdGenerateService.kt
@@ -0,0 +1,47 @@
+package dev.usbharu.hideout.service
+
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+import java.time.Instant
+
+open class SnowflakeIdGenerateService(private val baseTime:Long) : IdGenerateService {
+    var lastTimeStamp: Long = -1
+    var sequenceId: Int = 0
+    val mutex = Mutex()
+
+    @Throws(IllegalStateException::class)
+    override suspend fun generateId(): Long {
+        return mutex.withLock {
+
+            var timestamp = getTime()
+            if (timestamp < lastTimeStamp) {
+                while (timestamp <= lastTimeStamp) {
+                    delay(1L)
+                    timestamp = getTime()
+                }
+                //            throw IllegalStateException(" $lastTimeStamp $timestamp ${lastTimeStamp-timestamp}  ")
+            }
+            if (timestamp == lastTimeStamp) {
+                sequenceId++
+                if (sequenceId >= 4096) {
+                    while (timestamp <= lastTimeStamp) {
+                        delay(1L)
+                        timestamp = getTime()
+                    }
+                    sequenceId = 0
+                }
+            } else {
+                sequenceId = 0
+            }
+            lastTimeStamp = timestamp
+            return@withLock (timestamp - baseTime).shl(22).or(1L.shl(12)).or(sequenceId.toLong())
+        }
+
+
+    }
+
+    private fun getTime(): Long {
+        return Instant.now().toEpochMilli()
+    }
+}
diff --git a/src/main/kotlin/dev/usbharu/hideout/service/TwitterSnowflakeIdGenerateService.kt b/src/main/kotlin/dev/usbharu/hideout/service/TwitterSnowflakeIdGenerateService.kt
new file mode 100644
index 00000000..7eb6b391
--- /dev/null
+++ b/src/main/kotlin/dev/usbharu/hideout/service/TwitterSnowflakeIdGenerateService.kt
@@ -0,0 +1,4 @@
+package dev.usbharu.hideout.service
+
+// 2010-11-04T01:42:54.657
+object TwitterSnowflakeIdGenerateService : SnowflakeIdGenerateService(1288834974657L)
diff --git a/src/test/kotlin/dev/usbharu/hideout/service/TwitterSnowflakeIdGenerateServiceTest.kt b/src/test/kotlin/dev/usbharu/hideout/service/TwitterSnowflakeIdGenerateServiceTest.kt
new file mode 100644
index 00000000..d1d5ff60
--- /dev/null
+++ b/src/test/kotlin/dev/usbharu/hideout/service/TwitterSnowflakeIdGenerateServiceTest.kt
@@ -0,0 +1,35 @@
+package dev.usbharu.hideout.service
+
+//import kotlinx.coroutines.NonCancellable.message
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.coroutineScope
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.runBlocking
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+
+class TwitterSnowflakeIdGenerateServiceTest {
+    @Test
+    fun noDuplicateTest() = runBlocking {
+        val mutex = Mutex()
+        val mutableListOf = mutableListOf<Long>()
+        coroutineScope {
+
+            repeat(500000) {
+
+                launch(Dispatchers.IO) {
+                    val id = TwitterSnowflakeIdGenerateService.generateId()
+                    mutex.withLock {
+                        mutableListOf.add(id)
+
+                    }
+                }
+
+            }
+        }
+
+        assertEquals(0, mutableListOf.size - mutableListOf.toSet().size)
+    }
+}