Introduce TCP & UDP server port scanning utility

Prior to this commit the Spring Framework did not provide a public means for scanning for available server ports. However, the Spring Framework internally used a FreePortScanner in integration tests within its own test suite. Furthermore, Spring Integration 2.2 provides similar support in a SocketUtils class in the spring-integration-test module. This commit introduces SocketUtils in spring-core to replace the FreePortScanner which was previously only used internally within Spring's test suite. This new implementation is inspired by both Spring Framework's FreePortScanner and Spring Integration's SocketUtils and consequently attempts to merge the best of both previous implementations. Issue: SPR-8032
2026-06-08 17:33:33 +00:00 · 2013-06-15 02:38:19 +02:00
parent e12311e364
commit f311bf3daf
6 changed files with 516 additions and 119 deletions
@@ -0,0 +1,180 @@
+/*
+ * Copyright 2002-2013 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
+ *
+ * http://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 org.springframework.util;
+
+import java.util.SortedSet;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+import static org.springframework.util.SocketUtils.*;
+
+/**
+ * Unit tests for {@link SocketUtils}.
+ *
+ * @author Sam Brannen
+ * @since 4.0
+ */
+public class SocketUtilsTests {
+
+	private void assertPortInRange(int port, int minPort, int maxPort) {
+		assertTrue("port [" + port + "] >= " + minPort, port >= minPort);
+		assertTrue("port [" + port + "] <= " + maxPort, port <= maxPort);
+	}
+
+	private void assertAvailablePorts(SortedSet<Integer> ports, int numRequested, int minPort, int maxPort) {
+		assertEquals("number of ports requested", numRequested, ports.size());
+		for (int port : ports) {
+			assertPortInRange(port, minPort, maxPort);
+		}
+	}
+
+	// --- TCP -----------------------------------------------------------------
+
+	@Test(expected = IllegalArgumentException.class)
+	public void findAvailableTcpPortWithZeroMinPort() {
+		SocketUtils.findAvailableTcpPort(0);
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void findAvailableTcpPortWithNegativeMinPort() {
+		SocketUtils.findAvailableTcpPort(-500);
+	}
+
+	@Test
+	public void findAvailableTcpPort() {
+		int port = SocketUtils.findAvailableTcpPort();
+		assertPortInRange(port, PORT_RANGE_MIN, PORT_RANGE_MAX);
+	}
+
+	@Test
+	public void findAvailableTcpPortWithMin() {
+		int port = SocketUtils.findAvailableTcpPort(50000);
+		assertPortInRange(port, 50000, PORT_RANGE_MAX);
+	}
+
+	@Test
+	public void findAvailableTcpPortInRange() {
+		int minPort = 20000;
+		int maxPort = minPort + 1000;
+		int port = SocketUtils.findAvailableTcpPort(minPort, maxPort);
+		assertPortInRange(port, minPort, maxPort);
+	}
+
+	@Test
+	public void find4AvailableTcpPorts() {
+		findAvailableTcpPorts(4);
+	}
+
+	@Test
+	public void find50AvailableTcpPorts() {
+		findAvailableTcpPorts(50);
+	}
+
+	@Test
+	public void find4AvailableTcpPortsInRange() {
+		findAvailableTcpPorts(4, 30000, 35000);
+	}
+
+	@Test
+	public void find50AvailableTcpPortsInRange() {
+		findAvailableTcpPorts(50, 40000, 45000);
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void findAvailableTcpPortsWithRequestedNumberGreaterThanSizeOfRange() {
+		findAvailableTcpPorts(50, 45000, 45010);
+	}
+
+	private void findAvailableTcpPorts(int numRequested) {
+		SortedSet<Integer> ports = SocketUtils.findAvailableTcpPorts(numRequested);
+		assertAvailablePorts(ports, numRequested, PORT_RANGE_MIN, PORT_RANGE_MAX);
+	}
+
+	private void findAvailableTcpPorts(int numRequested, int minPort, int maxPort) {
+		SortedSet<Integer> ports = SocketUtils.findAvailableTcpPorts(numRequested, minPort, maxPort);
+		assertAvailablePorts(ports, numRequested, minPort, maxPort);
+	}
+
+	// --- UDP -----------------------------------------------------------------
+
+	@Test(expected = IllegalArgumentException.class)
+	public void findAvailableUdpPortWithZeroMinPort() {
+		SocketUtils.findAvailableUdpPort(0);
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void findAvailableUdpPortWithNegativeMinPort() {
+		SocketUtils.findAvailableUdpPort(-500);
+	}
+
+	@Test
+	public void findAvailableUdpPort() {
+		int port = SocketUtils.findAvailableUdpPort();
+		assertPortInRange(port, PORT_RANGE_MIN, PORT_RANGE_MAX);
+	}
+
+	@Test
+	public void findAvailableUdpPortWithMin() {
+		int port = SocketUtils.findAvailableUdpPort(50000);
+		assertPortInRange(port, 50000, PORT_RANGE_MAX);
+	}
+
+	@Test
+	public void findAvailableUdpPortInRange() {
+		int minPort = 20000;
+		int maxPort = minPort + 1000;
+		int port = SocketUtils.findAvailableUdpPort(minPort, maxPort);
+		assertPortInRange(port, minPort, maxPort);
+	}
+
+	@Test
+	public void find4AvailableUdpPorts() {
+		findAvailableUdpPorts(4);
+	}
+
+	@Test
+	public void find50AvailableUdpPorts() {
+		findAvailableUdpPorts(50);
+	}
+
+	@Test
+	public void find4AvailableUdpPortsInRange() {
+		findAvailableUdpPorts(4, 30000, 35000);
+	}
+
+	@Test
+	public void find50AvailableUdpPortsInRange() {
+		findAvailableUdpPorts(50, 40000, 45000);
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void findAvailableUdpPortsWithRequestedNumberGreaterThanSizeOfRange() {
+		findAvailableUdpPorts(50, 45000, 45010);
+	}
+
+	private void findAvailableUdpPorts(int numRequested) {
+		SortedSet<Integer> ports = SocketUtils.findAvailableUdpPorts(numRequested);
+		assertAvailablePorts(ports, numRequested, PORT_RANGE_MIN, PORT_RANGE_MAX);
+	}
+
+	private void findAvailableUdpPorts(int numRequested, int minPort, int maxPort) {
+		SortedSet<Integer> ports = SocketUtils.findAvailableUdpPorts(numRequested, minPort, maxPort);
+		assertAvailablePorts(ports, numRequested, minPort, maxPort);
+	}
+
+}