SocketUtils is internalized. The library has been changed.

build.gradle.kts

@@ -40,7 +40,7 @@ dependencies {
     implementation("org.springframework.boot:spring-boot-starter-test:$springBootVersion") {
         exclude(group = "com.vaadin.external.google")
     }
-    implementation("it.ozimov:embedded-redis:$embeddedRedisVersion") {
+    implementation("org.signal:embedded-redis:$embeddedRedisVersion") {
         exclude(group = "org.slf4j", module = "slf4j-simple")
     }
     testImplementation("org.springframework.boot:spring-boot-starter:$springBootVersion")

gradle.properties

@@ -3,7 +3,7 @@ org.gradle.warning.mode=all
 org.gradle.jvmargs=-XX:MaxMetaspaceSize=2G
 
 springBootVersion=2.5.2
-embeddedRedisVersion=0.7.3
+embeddedRedisVersion=0.8.3
 lettuceVersion=6.1.4.RELEASE
 jUnitVersion=5.7.0
 kotlin.version=1.5.20

src/main/kotlin/com/asarkar/spring/test/redis/EmbeddedRedisApplicationListener.kt

@@ -5,7 +5,6 @@ import org.springframework.context.ApplicationListener
 import org.springframework.core.Ordered
 import org.springframework.core.annotation.Order
 import org.springframework.core.env.MapPropertySource
-import org.springframework.util.SocketUtils
 
 @Order(Ordered.LOWEST_PRECEDENCE)
 open class EmbeddedRedisApplicationListener : ApplicationListener<ApplicationPreparedEvent> {

src/main/kotlin/com/asarkar/spring/test/redis/SocketUtils.kt

@@ -0,0 +1,153 @@
+/*
+ * Copyright 2002-2020 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.asarkar.spring.test.redis
+
+import org.springframework.util.Assert
+import java.net.DatagramSocket
+import java.net.InetAddress
+import java.net.ServerSocket
+import java.util.Random
+import javax.net.ServerSocketFactory
+
+/**
+ * Simple utility methods for working with network sockets  for example,
+ * for finding available ports on `localhost`.
+ *
+ * Within this class, a TCP port refers to a port for a [ServerSocket];
+ * whereas, a UDP port refers to a port for a [DatagramSocket].
+ *
+ * org.springframework.util.SocketUtils was removed in Spring 6.
+ * From Springboot 3.2.3 version, SocketUtils cannot be used.
+ * org.springframework.test.util.TestSocketUtils can be used as an alternative, but embedded-redis-spring has to support older versions, so org.springframework.util.SocketUtils was copied.
+ *
+ * @author Sam Brannen
+ * @author Ben Hale
+ * @author Arjen Poutsma
+ * @author Gunnar Hillert
+ * @author Gary Russell
+ * @author fennec-fox
+ * @since 4.0
+ */
+object SocketUtils {
+    /**
+     * The default minimum value for port ranges used when finding an available
+     * socket port.
+     */
+    private const val PORT_RANGE_MIN: Int = 1024
+
+    /**
+     * The default maximum value for port ranges used when finding an available
+     * socket port.
+     */
+    const val PORT_RANGE_MAX: Int = 65535
+
+    private val random = Random(System.nanoTime())
+
+    /**
+     * Find an available TCP port randomly selected from the range
+     * [`minPort`, `maxPort`].
+     * @param minPort the minimum port number
+     * @param maxPort the maximum port number
+     * @return an available TCP port number
+     * @throws IllegalStateException if no available port could be found
+     */
+    /**
+     * Find an available TCP port randomly selected from the range
+     * [`minPort`, {@value #PORT_RANGE_MAX}].
+     * @param minPort the minimum port number
+     * @return an available TCP port number
+     * @throws IllegalStateException if no available port could be found
+     */
+    /**
+     * Find an available TCP port randomly selected from the range
+     * [{@value #PORT_RANGE_MIN}, {@value #PORT_RANGE_MAX}].
+     * @return an available TCP port number
+     * @throws IllegalStateException if no available port could be found
+     */
+    @JvmOverloads
+    fun findAvailableTcpPort(minPort: Int = PORT_RANGE_MIN, maxPort: Int = PORT_RANGE_MAX): Int {
+        return SocketType.TCP.findAvailablePort(minPort, maxPort)
+    }
+
+    private enum class SocketType {
+        TCP {
+            override fun isPortAvailable(port: Int): Boolean {
+                try {
+                    val serverSocket = ServerSocketFactory.getDefault().createServerSocket(
+                        port,
+                        1,
+                        InetAddress.getByName("localhost")
+                    )
+                    serverSocket.close()
+                    return true
+                } catch (ex: Exception) {
+                    return false
+                }
+            }
+        };
+
+        /**
+         * Determine if the specified port for this `SocketType` is
+         * currently available on `localhost`.
+         */
+        protected abstract fun isPortAvailable(port: Int): Boolean
+
+        /**
+         * Find a pseudo-random port number within the range
+         * [`minPort`, `maxPort`].
+         * @param minPort the minimum port number
+         * @param maxPort the maximum port number
+         * @return a random port number within the specified range
+         */
+        private fun findRandomPort(minPort: Int, maxPort: Int): Int {
+            val portRange = maxPort - minPort
+            return minPort + random.nextInt(portRange + 1)
+        }
+
+        /**
+         * Find an available port for this `SocketType`, randomly selected
+         * from the range [`minPort`, `maxPort`].
+         * @param minPort the minimum port number
+         * @param maxPort the maximum port number
+         * @return an available port number for this socket type
+         * @throws IllegalStateException if no available port could be found
+         */
+        fun findAvailablePort(minPort: Int, maxPort: Int): Int {
+            Assert.isTrue(minPort > 0, "'minPort' must be greater than 0")
+            Assert.isTrue(maxPort >= minPort, "'maxPort' must be greater than or equal to 'minPort'")
+            Assert.isTrue(maxPort <= PORT_RANGE_MAX, "'maxPort' must be less than or equal to $PORT_RANGE_MAX")
+
+            val portRange = maxPort - minPort
+            var candidatePort: Int
+            var searchCounter = 0
+            do {
+                check(searchCounter <= portRange) {
+                    String.format(
+                        "Could not find an available %s port in the range [%d, %d] after %d attempts",
+                        name,
+                        minPort,
+                        maxPort,
+                        searchCounter
+                    )
+                }
+                candidatePort = findRandomPort(minPort, maxPort)
+                searchCounter++
+            } while (!isPortAvailable(candidatePort))
+
+            return candidatePort
+        }
+    }
+}