Change classes, make it work

.idea/inspectionProfiles/Project_Default.xml

@@ -0,0 +1,8 @@
+<component name="InspectionProjectProfileManager">
+  <profile version="1.0">
+    <option name="myName" value="Project Default" />
+    <inspection_tool class="AutoCloseableResource" enabled="true" level="WARNING" enabled_by_default="true">
+      <option name="METHOD_MATCHER_CONFIG" value="java.util.Formatter,format,java.io.Writer,append,com.google.common.base.Preconditions,checkNotNull,org.hibernate.Session,close,java.io.PrintWriter,printf,java.io.PrintStream,printf,java.util.concurrent.Executors,newVirtualThreadPerTaskExecutor" />
+    </inspection_tool>
+  </profile>
+</component>

.idea/misc.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_21" default="true" project-jdk-name="21" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_21" default="true" project-jdk-name="openjdk-21" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>

.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>

src/BaseMonitor.java

@@ -1,16 +1,23 @@
 import java.io.IOException;
 
-public abstract class BaseMonitor {
+public abstract class BaseMonitor implements Runnable {
     private final String friendlyName;
     private final String target;
     private final int interval;
     private final int timeout;
+    private MonitorStatus prevCheckStatus;
 
+    public enum MonitorStatus {
+        ONLINE,
+        OFFLINE,
+        UNKNOWN
+    }
     public BaseMonitor(String name, String target) {
         this.friendlyName = name;
         this.target = target;
-        this.interval = 120;
+        this.interval = 5000;
-        this.timeout = 5000;
+        this.timeout = 15000;
+        this.prevCheckStatus = MonitorStatus.UNKNOWN;
     }
 
     public String getFriendlyName() {
@@ -29,13 +36,34 @@ public abstract class BaseMonitor {
         return timeout;
     }
 
-    public abstract boolean check() throws IOException;
+    public void setPrevCheckStatus(MonitorStatus newStatus) {
+        this.prevCheckStatus = newStatus;
+    }
+    public abstract MonitorStatus check() throws IOException, InterruptedException;
 
-    public void checkCmd() throws IOException {
+//    public void checkCmd() throws IOException, InterruptedException {
-        if (this.check()) {
+//        MonitorStatus currStatus = this.check();
-            System.out.println(this.getFriendlyName() + ", with address '" + this.getTarget() + "' is online!");
+//
-        } else {
+//        if (currStatus == MonitorStatus.ONLINE) {
-            System.out.println(this.getFriendlyName() + ", with address '" + this.getTarget() + "' is offline!");
+//            System.out.println(this.getFriendlyName() + ", with address '" + this.getTarget() + "' is online!");
+//        } else if (currStatus == MonitorStatus.OFFLINE) {
+//            System.out.println(this.getFriendlyName() + ", with address '" + this.getTarget() + "' is offline!");
+//        }
+//    }
+    @Override
+    public void run() {
+        System.out.println("Monitor '" + this.friendlyName + "' start status: " + this.prevCheckStatus);
+        while (true) {
+            try {
+                MonitorStatus prevStatus = this.prevCheckStatus;
+                MonitorStatus checkStatus = this.check();
+                if (prevStatus != checkStatus) {
+                    System.out.println("Monitor '" + this.getFriendlyName() + "', changed, new status: " + checkStatus);
+                }
+                Thread.sleep(this.getInterval());
+            } catch (IOException | InterruptedException e) {
+                throw new RuntimeException(e);
+            }
         }
     }
 }

src/HTTPMonitor.java

@@ -8,9 +8,12 @@ public class HTTPMonitor extends BaseMonitor{
     }
 
     @Override
-    public boolean check() throws IOException {
+    public MonitorStatus check() throws IOException {
         URI uri = URI.create(super.getTarget());
         HttpsURLConnection conn = (HttpsURLConnection) uri.toURL().openConnection();
-        return conn.getResponseCode() == 200;
+        MonitorStatus checkStatus = (conn.getResponseCode() == 200) ? MonitorStatus.ONLINE : MonitorStatus.OFFLINE;
+
+        super.setPrevCheckStatus(checkStatus);
+        return checkStatus;
     }
 }

src/ICMPMonitor.java

@@ -1,5 +1,4 @@
 import java.io.IOException;
-import java.net.InetAddress;
 
 public class ICMPMonitor extends BaseMonitor{
     public ICMPMonitor(String name, String target) {
@@ -7,8 +6,20 @@ public class ICMPMonitor extends BaseMonitor{
     }
 
     @Override
-    public boolean check() throws IOException {
+    public MonitorStatus check() throws IOException, InterruptedException {
-        InetAddress address = InetAddress.getByName(super.getTarget());
+        Process p1 = java.lang.Runtime.getRuntime().exec("ping -c 1 " + this.getTarget());
-        return address.isReachable(super.getTimeout());
+        int returnVal = p1.waitFor();
+        if (returnVal==0) {
+            return MonitorStatus.ONLINE;
+        } else {
+            return MonitorStatus.OFFLINE;
+        }
+//        InetAddress address = InetAddress.getByName(super.getTarget());
+//        return address.isReachable(super.getTimeout());
+    }
+
+    @Override
+    public void run() {
+
     }
 }

src/Main.java

@@ -1,11 +1,23 @@
 import java.io.IOException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
 
 public class Main {
-    public static void main(String[] args) throws IOException {
+    public static void main(String[] args) throws InterruptedException {
-        ICMPMonitor cloudFlareIcmpMonitor = new ICMPMonitor("Oracle Server 01", "srv01.oci.mzsl.nl");
+//        ICMPMonitor cloudFlareIcmpMonitor = new ICMPMonitor("Oracle Server 01", "srv01.oci.mzsl.nl");
-        HTTPMonitor mzieselHttpMonit = new HTTPMonitor("Website van Mans", "https://mziesel.nl/bestaat-niet");
+        HTTPMonitor mzieselHttpMonit = new HTTPMonitor("Website van Mans", "https://mziesel.nl/");
+        HTTPMonitor testHttpMonit = new HTTPMonitor("Test website", "https://whoami.mzsl.nl/");
+        HTTPMonitor mcaHttpMonit = new HTTPMonitor("Microcenter website", "https://microcenter.nl/");
 
-        cloudFlareIcmpMonitor.checkCmd();
+        ExecutorService executorService = Executors.newVirtualThreadPerTaskExecutor();
-        mzieselHttpMonit.checkCmd();
+
+        executorService.execute(mzieselHttpMonit);
+        executorService.execute(testHttpMonit);
+        executorService.execute(mcaHttpMonit);
+
+        while (!executorService.isTerminated()) {
+            Thread.sleep(1000);
+        }
     }
 }