convert code java to kotlin

Author: Hyeon9mak

build.gradle

@@ -0,0 +1,55 @@
+plugins {
+    kotlin("jvm") version "1.6.21"
+    kotlin("plugin.spring") version "1.6.21"
+    kotlin("plugin.jpa") version "1.6.21"
+    id("org.springframework.boot") version "2.7.18" apply false
+    id("io.spring.dependency-management") version "1.0.15.RELEASE"
+    id("maven-publish")
+}
+
+group = "hyeon9mak"
+version = "2.2.0-spring-boot-2"
+
+java {
+    sourceCompatibility = JavaVersion.VERSION_1_8
+    targetCompatibility = JavaVersion.VERSION_1_8
+}
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    implementation("org.springframework.boot:spring-boot-starter-web")
+    implementation("org.springframework.boot:spring-boot-starter-data-jpa")
+    implementation("org.springframework.boot:spring-boot-starter-aop")
+    implementation("io.github.microutils:kotlin-logging-jvm:2.1.23")
+    implementation("org.jetbrains.kotlin:kotlin-reflect")
+    implementation("com.fasterxml.jackson.module:jackson-module-kotlin")
+    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.6.4")
+}
+
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile> {
+    kotlinOptions {
+        freeCompilerArgs = listOf("-Xjsr305=strict")
+        jvmTarget = "1.8"
+    }
+}
+
+dependencyManagement {
+    imports {
+        mavenBom(org.springframework.boot.gradle.plugin.SpringBootPlugin.BOM_COORDINATES)
+    }
+}
+
+publishing {
+    publications {
+        create<MavenPublication>("maven") {
+            groupId = project.group.toString()
+            artifactId = project.name
+            version = project.version.toString()
+
+            from(components["java"])
+        }
+    }
+}

build.gradle.kts

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.8-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.6.2-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME

gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,8 @@
+package hyeon9mak.multidatasourcequerycounter
+
+import org.springframework.boot.autoconfigure.AutoConfiguration
+import org.springframework.context.annotation.ComponentScan
+
+@ComponentScan("hyeon9mak.multidatasourcequerycounter")
+@AutoConfiguration
+class AutoConfig

settings.gradle renamed to settings.gradle.kts

@@ -0,0 +1,35 @@
+package hyeon9mak.multidatasourcequerycounter
+
+import org.aopalliance.intercept.MethodInterceptor
+import org.aopalliance.intercept.MethodInvocation
+import org.springframework.aop.framework.ProxyFactory
+
+class ConnectionQueryMonitor(
+    private val queryCountPerRequest: QueryCountPerRequest,
+    private val connection: Any,
+) : MethodInterceptor {
+
+    override fun invoke(invocation: MethodInvocation): Any? {
+        val result = invocation.proceed()
+
+        if (result != null && invocation.preparedStatementInvoked()) {
+            val proxyFactory = ProxyFactory(result)
+            proxyFactory.addAdvice(PreparedStatementQueryMonitor(queryCountPerRequest = queryCountPerRequest))
+            return proxyFactory.proxy
+        }
+
+        return result
+    }
+
+    fun getProxy(): Any {
+        val proxyFactory = ProxyFactory(connection)
+        proxyFactory.addAdvice(this)
+        return proxyFactory.proxy
+    }
+
+    private fun MethodInvocation.preparedStatementInvoked(): Boolean = this.method.name == JDBC_PREPARE_STATEMENT_METHOD_NAME
+
+    companion object {
+        private const val JDBC_PREPARE_STATEMENT_METHOD_NAME = "prepareStatement"
+    }
+}

src/main/java/hyeon9mak/multidatasourcequerycounter/AutoConfig.java

@@ -0,0 +1,28 @@
+package hyeon9mak.multidatasourcequerycounter
+
+import kotlinx.coroutines.ThreadContextElement
+import org.springframework.web.context.request.RequestAttributes
+import org.springframework.web.context.request.RequestContextHolder
+import kotlin.coroutines.CoroutineContext
+
+/**
+ * https://kotlinlang.org/api/kotlinx.coroutines/kotlinx-coroutines-core/kotlinx.coroutines/-thread-context-element/
+ */
+class CoroutineQueryCountContextElement(
+    private val requestAttributes: RequestAttributes = RequestContextHolder.currentRequestAttributes(),
+) : ThreadContextElement<RequestAttributes> {
+
+    companion object Key : CoroutineContext.Key<CoroutineQueryCountContextElement>
+
+    override val key: CoroutineContext.Key<CoroutineQueryCountContextElement>
+        get() = Key
+
+    override fun updateThreadContext(context: CoroutineContext): RequestAttributes {
+        RequestContextHolder.setRequestAttributes(requestAttributes)
+        return requestAttributes
+    }
+
+    override fun restoreThreadContext(context: CoroutineContext, oldState: RequestAttributes) {
+        RequestContextHolder.setRequestAttributes(oldState)
+    }
+}

src/main/java/hyeon9mak/multidatasourcequerycounter/AutoConfig.kt

@@ -0,0 +1,10 @@
+package hyeon9mak.multidatasourcequerycounter
+
+@Target(AnnotationTarget.FUNCTION, AnnotationTarget.CLASS)
+@Retention(AnnotationRetention.RUNTIME)
+annotation class CountQueries(
+    /**
+     * prefix for query count log message.
+     */
+    val prefix: String = ""
+)

src/main/java/hyeon9mak/multidatasourcequerycounter/ConnectionQueryMonitor.java

@@ -0,0 +1,47 @@
+package hyeon9mak.multidatasourcequerycounter
+
+import org.aspectj.lang.ProceedingJoinPoint
+import org.aspectj.lang.annotation.Around
+import org.aspectj.lang.annotation.Aspect
+import org.aspectj.lang.reflect.MethodSignature
+import org.springframework.stereotype.Component
+import org.springframework.web.context.request.RequestContextHolder
+import org.springframework.web.context.request.ServletRequestAttributes
+
+@Aspect
+@Component
+class HikariDataSourceQueryCounter(
+    private val queryCountPerRequest: QueryCountPerRequest,
+    private val queryCountLogger: QueryCountLogger,
+) {
+    @Around("execution( * com.zaxxer.hikari.HikariDataSource.getConnection())")
+    fun aroundConnection(joinPoint: ProceedingJoinPoint): Any {
+        val connection = joinPoint.proceed()
+        val connectionQueryMonitor = ConnectionQueryMonitor(queryCountPerRequest, connection)
+        return connectionQueryMonitor.getProxy()
+    }
+
+    @Around("@annotation(countQueries)")
+    fun aroundCountQueriesMethod(joinPoint: ProceedingJoinPoint, countQueries: CountQueries): Any {
+        val result = joinPoint.proceed()
+
+        val attributes = RequestContextHolder.getRequestAttributes() as ServletRequestAttributes?
+
+        if (attributes.isInRequestScope) {
+            val request = attributes!!.request
+            queryCountPerRequest.apiUrl = request.method + " " + request.requestURI
+        } else {
+            val methodSignature = joinPoint.signature as MethodSignature
+            val methodName = methodSignature.method.name
+            val className = methodSignature.declaringType.simpleName
+            queryCountPerRequest.apiUrl = countQueries.prefix + className + "." + methodName
+        }
+
+        queryCountLogger.logQueryCount(queryCountPerRequest)
+
+        return result
+    }
+
+    private val ServletRequestAttributes?.isInRequestScope: Boolean
+        get() = this != null
+}