Fixed Failing EchoTest

core-java/src/main/java/com/baeldung/java/nio/selector/EchoServer.java

@@ -1,14 +1,15 @@
 package com.baeldung.java.nio.selector;
 
+import java.io.File;
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.SelectionKey;
+import java.nio.channels.Selector;
 import java.nio.channels.ServerSocketChannel;
 import java.nio.channels.SocketChannel;
-import java.nio.channels.Selector;
-import java.nio.channels.SelectionKey;
-import java.nio.ByteBuffer;
-import java.io.IOException;
-import java.util.Set;
 import java.util.Iterator;
-import java.net.InetSocketAddress;
+import java.util.Set;
 
 public class EchoServer {
 
@@ -47,4 +48,15 @@ public class EchoServer {
             }
         }
     }
-}
+
+    public static Process start() throws IOException, InterruptedException {
+        String javaHome = System.getProperty("java.home");
+        String javaBin = javaHome + File.separator + "bin" + File.separator + "java";
+        String classpath = System.getProperty("java.class.path");
+        String className = EchoServer.class.getCanonicalName();
+
+        ProcessBuilder builder = new ProcessBuilder(javaBin, "-cp", classpath, className);
+
+        return builder.start();
+    }
+}

core-java/src/test/java/com/baeldung/java/nio/selector/EchoTest.java

@@ -2,17 +2,20 @@ package com.baeldung.java.nio.selector;
 
 import static org.junit.Assert.assertEquals;
 
+import java.io.IOException;
+
 import org.junit.Test;
 
 public class EchoTest {
 
     @Test
-    public void givenClient_whenServerEchosMessage_thenCorrect() {
+    public void givenClient_whenServerEchosMessage_thenCorrect() throws IOException, InterruptedException {
+        Process process = EchoServer.start();
         EchoClient client = EchoClient.start();
         String resp1 = client.sendMessage("hello");
         String resp2 = client.sendMessage("world");
         assertEquals("hello", resp1);
         assertEquals("world", resp2);
+        process.destroy();
     }
-
 }