[ANT] De-duplicat SecurityManager support check and update remote.jar

Also remove obsolete comments.

Follow-up on
#1662

ant/org.eclipse.ant.core/src_ant/org/eclipse/ant/internal/core/ant/InternalAntRunner.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- *  Copyright (c) 2000, 2022 IBM Corporation and others.
+ *  Copyright (c) 2000, 2024 IBM Corporation and others.
  *
  *  This program and the accompanying materials
  *  are made available under the terms of the Eclipse Public License 2.0
@@ -83,7 +83,7 @@
 @SuppressWarnings("removal") // SecurityManager
 public class InternalAntRunner {
 
-	private static final boolean IS_SECURITY_MANAGER_SUPPORTED = isSecurityManagerAllowed();
+	public static final boolean IS_SECURITY_MANAGER_SUPPORTED = isSecurityManagerAllowed();
 
 	private static boolean isSecurityManagerAllowed() {
 		String sm = System.getProperty("java.security.manager"); //$NON-NLS-1$
@@ -708,8 +708,6 @@ private void run(List<String> argList) {
 				printArguments(getCurrentProject());
 			}
 			if (IS_SECURITY_MANAGER_SUPPORTED) {
-				// TODO: call SecurityManagerUtil.isSecurityManagerAllowed() once it's more fine-grained,
-				// i.e. once https://github.com/apache/ant/pull/216 is available.
 				System.setSecurityManager(new AntSecurityManager(originalSM, Thread.currentThread()));
 			}
 			if (targets == null) {

ant/org.eclipse.ant.ui/Ant Tools Support/org/eclipse/ant/internal/ui/model/AntModel.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2022 IBM Corporation and others.
+ * Copyright (c) 2000, 2024 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
@@ -49,7 +49,6 @@
 import org.apache.tools.ant.Task;
 import org.apache.tools.ant.TaskAdapter;
 import org.apache.tools.ant.UnknownElement;
-import org.apache.tools.ant.util.JavaEnvUtils;
 import org.eclipse.ant.core.AntCorePlugin;
 import org.eclipse.ant.core.AntCorePreferences;
 import org.eclipse.ant.core.AntSecurityException;
@@ -59,6 +58,7 @@
 import org.eclipse.ant.internal.core.AntCoreUtil;
 import org.eclipse.ant.internal.core.AntSecurityManager;
 import org.eclipse.ant.internal.core.IAntCoreConstants;
+import org.eclipse.ant.internal.core.ant.InternalAntRunner;
 import org.eclipse.ant.internal.ui.AntUIPlugin;
 import org.eclipse.ant.internal.ui.AntUtil;
 import org.eclipse.ant.internal.ui.editor.DecayCodeCompletionDataStructuresThread;
@@ -90,17 +90,6 @@
 @SuppressWarnings("removal") // SecurityManager
 public class AntModel implements IAntModel {
 
-	private static final boolean IS_SECURITY_MANAGER_SUPPORTED = isSecurityManagerAllowed();
-
-	private static boolean isSecurityManagerAllowed() {
-		String sm = System.getProperty("java.security.manager"); //$NON-NLS-1$
-		if (sm == null) { // default is 'disallow' since 18 and was 'allow' before
-			return !JavaEnvUtils.isAtLeastJavaVersion("18"); //$NON-NLS-1$
-		}
-		// Value is either 'disallow' or 'allow' or specifies the SecurityManager class to set
-		return !"disallow".equals(sm); //$NON-NLS-1$
-	}
-
 	private static ClassLoader fgClassLoader;
 	private static int fgInstanceCount = 0;
 	private static Object loaderLock = new Object();
@@ -375,7 +364,9 @@ private void parseDocument(IDocument input) {
 				SecurityManager origSM = System.getSecurityManager();
 				processAntHome(true);
 				try {
-					if (IS_SECURITY_MANAGER_SUPPORTED) {
+					@SuppressWarnings("restriction")
+					boolean isSecurityManagerSupported = InternalAntRunner.IS_SECURITY_MANAGER_SUPPORTED;
+					if (isSecurityManagerSupported) {
 						// set a security manager to disallow system exit and system property setting
 						System.setSecurityManager(new AntSecurityManager(origSM, Thread.currentThread(), false));
 					}