Add check for release < JRE in JavaSearchPage

- modify JavaSearchPage.updateOKStatus() to check if release set
  is less than the default JRE in which case, issue a warning message
  on the page
- fixes eclipse-jdt#2017

Author: jjohnstn

org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/search/JavaSearchPage.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2017 IBM Corporation and others.
+ * Copyright (c) 2000, 2025 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
@@ -13,6 +13,7 @@
  *******************************************************************************/
 package org.eclipse.jdt.internal.ui.search;
 
+import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -78,6 +79,9 @@
 
 import org.eclipse.jdt.internal.corext.util.Messages;
 
+import org.eclipse.jdt.launching.IVMInstall2;
+import org.eclipse.jdt.launching.JavaRuntime;
+
 import org.eclipse.jdt.ui.search.ElementQuerySpecification;
 import org.eclipse.jdt.ui.search.PatternQuerySpecification;
 import org.eclipse.jdt.ui.search.QuerySpecification;
@@ -283,6 +287,7 @@ public static SearchPatternData create(IDialogSettings settings) {
 	private Button[] fLimitTo;
 	private Button[] fIncludeMasks;
 	private Group fLimitToGroup;
+	private Label fMessageLabel;
 
 	private int fMatchLocations;
 	private Link fMatchLocationsLink;
@@ -540,6 +545,9 @@ public void createControl(Composite parent) {
 		Control includeMask= createIncludeMask(result);
 		includeMask.setLayoutData(new GridData(GridData.FILL, GridData.FILL, true, false, 2, 1));
 
+		Control messageLabel= createMessageLabel(result);
+		messageLabel.setLayoutData(new GridData(GridData.FILL, GridData.FILL, true, false, 2, 1));
+
 		//createParticipants(result);
 
 		SelectionAdapter javaElementInitializer= new SelectionAdapter() {
@@ -588,6 +596,18 @@ public void widgetSelected(SelectionEvent e) {
 	}*/
 
 
+	private Control createMessageLabel(Composite parent) {
+		Composite result= new Composite(parent, SWT.NONE);
+		GridLayout layout= new GridLayout(1, false);
+		layout.marginWidth= 5;
+		layout.marginHeight= 5;
+		result.setLayout(layout);
+
+		fMessageLabel= new Label(result, SWT.NONE);
+		fMessageLabel.setLayoutData(new GridData(GridData.FILL, GridData.FILL, true, false, 1, 1));
+		return result;
+	}
+
 	private Control createExpression(Composite parent) {
 		Composite result= new Composite(parent, SWT.NONE);
 		GridLayout layout= new GridLayout(2, false);
@@ -637,6 +657,20 @@ public void widgetSelected(SelectionEvent e) {
 	final void updateOKStatus() {
 		boolean isValidPattern= isValidSearchPattern();
 		boolean isValidMask= getIncludeMask() != 0;
+		fMessageLabel.setText(""); //$NON-NLS-1$
+		if ((getIncludeMask() & JavaSearchScopeFactory.JRE) != 0) {
+			String release= JavaCore.getOption(JavaCore.COMPILER_RELEASE);
+			if (release.equals(JavaCore.ENABLED)) {
+				String compliance= JavaCore.getOption(JavaCore.COMPILER_COMPLIANCE);
+				if (compliance != null) {
+					if (JavaRuntime.getVMInstall(JavaRuntime.newDefaultJREContainerPath()) instanceof IVMInstall2 jreInstall) {
+						if (JavaCore.compareJavaVersions(compliance, jreInstall.getJavaVersion()) < 0) {
+							fMessageLabel.setText(MessageFormat.format(SearchMessages.JavaSearchPage_release_warning_message, compliance, jreInstall.getJavaVersion()));
+						}
+					}
+				}
+			}
+		}
 		getContainer().setPerformActionEnabled(isValidPattern && isValidMask);
 	}
 

org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/search/SearchMessages.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2022 IBM Corporation and others.
+ * Copyright (c) 2000, 2025 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
@@ -154,6 +154,7 @@ private SearchMessages() {
 	public static String JavaSearchPage_match_location_link_label;
 	public static String JavaSearchPage_match_location_link_label_tooltip;
 	public static String JavaSearchPage_match_locations_label;
+	public static String JavaSearchPage_release_warning_message;
 	public static String JavaElementAction_typeSelectionDialog_title;
 	public static String JavaElementAction_typeSelectionDialog_message;
 	public static String JavaElementAction_error_open_message;

org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/search/SearchMessages.properties

@@ -1,5 +1,5 @@
 ###############################################################################
-# Copyright (c) 2000, 2022 IBM Corporation and others.
+# Copyright (c) 2000, 2025 IBM Corporation and others.
 #
 # This program and the accompanying materials
 # are made available under the terms of the Eclipse Public License 2.0
@@ -157,6 +157,7 @@ JavaSearchOperation_pluralOccurrencesPostfix=''{0}'' - {1} occurrences in {2}
 JavaSearchPage_match_location_link_label=(<a>{0} of {1} selected</a>)
 JavaSearchPage_match_location_link_label_tooltip=Configure the selected match locations
 JavaSearchPage_match_locations_label=M&atch locations
+JavaSearchPage_release_warning_message=Warning: cannot reliably get source code for release {0} from JRE {1}
 JavaElementAction_typeSelectionDialog_title=Search
 JavaElementAction_typeSelectionDialog_message=&Select the type to search:
 JavaElementAction_error_open_message=An exception occurred while opening the type.