[organize imports] Add preferences to keep existing star imports and to disable collapsing

org.eclipse.jdt.core.manipulation/common/org/eclipse/jdt/core/manipulation/CodeStyleConfiguration.java

@@ -22,6 +22,8 @@
 import org.eclipse.jdt.core.dom.CompilationUnit;
 import org.eclipse.jdt.core.dom.rewrite.ImportRewrite;
 
+import org.eclipse.jdt.internal.corext.codemanipulation.CodeGenerationSettingsConstants;
+
 /**
  * Gives access to the import rewrite configured with the settings as specified in the user interface.
  * These settings are kept in JDT UI for compatibility reasons.
@@ -125,6 +127,14 @@
 		} catch (NumberFormatException e) {
 			// ignore
 		}
+
+		String keepExisting= JavaManipulation.getPreference(CodeGenerationSettingsConstants.ORGIMPORTS_KEEP_EXISTING_ONDEMAND, project);
+		rewrite.setKeepExistingOnDemandImports(Boolean.parseBoolean(keepExisting));
+
+		String collapse= JavaManipulation.getPreference(CodeGenerationSettingsConstants.ORGIMPORTS_COLLAPSE_TO_ONDEMAND, project);
+		// Defaults to true, so a missing preference must be treated as enabled.
+		rewrite.setCollapseSingleImportsToOnDemand(collapse == null || Boolean.parseBoolean(collapse));
+
 		return rewrite;
 	}
 

org.eclipse.jdt.core.manipulation/core extension/org/eclipse/jdt/internal/corext/codemanipulation/CodeGenerationSettingsConstants.java

@@ -59,6 +59,27 @@ public class CodeGenerationSettingsConstants {
 	 */
 	public static final String ORGIMPORTS_IGNORELOWERCASE= "org.eclipse.jdt.ui.ignorelowercasenames"; //$NON-NLS-1$
 
+	/**
+	 * A named preference that controls whether existing on-demand (".*") imports are preserved as
+	 * on-demand imports by the "Organize Imports" operation, instead of being expanded into single
+	 * imports.
+	 * <p>
+	 * Value is of type <code>Boolean</code>.
+	 * </p>
+	 */
+	public static final String ORGIMPORTS_KEEP_EXISTING_ONDEMAND= "org.eclipse.jdt.ui.organizeimports.keepexistingondemand"; //$NON-NLS-1$
+
+	/**
+	 * A named preference that controls whether the "Organize Imports" operation may collapse single
+	 * imports into a new on-demand (".*") import once the on-demand threshold is reached. When
+	 * disabled, the thresholds are ignored and no new on-demand import is created from single
+	 * imports.
+	 * <p>
+	 * Value is of type <code>Boolean</code>.
+	 * </p>
+	 */
+	public static final String ORGIMPORTS_COLLAPSE_TO_ONDEMAND= "org.eclipse.jdt.ui.organizeimports.collapsetoondemand"; //$NON-NLS-1$
+
 	private CodeGenerationSettingsConstants() {
 	}
 

org.eclipse.jdt.ui.tests/ui/org/eclipse/jdt/ui/tests/core/ImportOrganizeTest.java

@@ -3255,6 +3255,123 @@ static public class Test {
 		assertEqualString(cu.getSource(), str1);
 	}
 
+	@Test
+	public void testKeepExistingOnDemandImport() throws Exception {
+		IPackageFragmentRoot sourceFolder= JavaProjectHelper.addSourceContainer(fJProject1, "src");
+
+		IPackageFragment pack1= sourceFolder.createPackageFragment("pack1", false, null);
+		String str= """
+			package pack1;
+
+			import java.util.*;
+
+			public class C {
+			    Map<String, String> m;
+			    Set<String> s;
+			}
+			""";
+		ICompilationUnit cu= pack1.createCompilationUnit("C.java", str, false, null);
+
+		String[] order= new String[] { "", "#" };
+		IChooseImportQuery query= createQuery("C", new String[] {}, new int[] {});
+
+		OrganizeImportsOperation op= createOperation(cu, order, 99, false, true, true, query);
+		setKeepExistingAndCollapse(cu.getJavaProject(), true, true);
+		op.run(null);
+
+		// The existing on-demand import is preserved instead of being expanded into single imports.
+		String expected= """
+			package pack1;
+
+			import java.util.*;
+
+			public class C {
+			    Map<String, String> m;
+			    Set<String> s;
+			}
+			""";
+		assertEqualString(cu.getSource(), expected);
+	}
+
+	@Test
+	public void testExistingOnDemandImportExpandedByDefault() throws Exception {
+		IPackageFragmentRoot sourceFolder= JavaProjectHelper.addSourceContainer(fJProject1, "src");
+
+		IPackageFragment pack1= sourceFolder.createPackageFragment("pack1", false, null);
+		String str= """
+			package pack1;
+
+			import java.util.*;
+
+			public class C {
+			    Map<String, String> m;
+			    Set<String> s;
+			}
+			""";
+		ICompilationUnit cu= pack1.createCompilationUnit("C.java", str, false, null);
+
+		String[] order= new String[] { "", "#" };
+		IChooseImportQuery query= createQuery("C", new String[] {}, new int[] {});
+
+		OrganizeImportsOperation op= createOperation(cu, order, 99, false, true, true, query);
+		setKeepExistingAndCollapse(cu.getJavaProject(), false, true);
+		op.run(null);
+
+		// With the default settings the on-demand import is expanded into single imports.
+		String expected= """
+			package pack1;
+
+			import java.util.Map;
+			import java.util.Set;
+
+			public class C {
+			    Map<String, String> m;
+			    Set<String> s;
+			}
+			""";
+		assertEqualString(cu.getSource(), expected);
+	}
+
+	@Test
+	public void testDoNotCollapseSingleImportsToOnDemand() throws Exception {
+		IPackageFragmentRoot sourceFolder= JavaProjectHelper.addSourceContainer(fJProject1, "src");
+
+		IPackageFragment pack1= sourceFolder.createPackageFragment("pack1", false, null);
+		String str= """
+			package pack1;
+
+			public class C {
+			    Collection<String> c;
+			    Map<String, String> m;
+			    Set<String> s;
+			}
+			""";
+		ICompilationUnit cu= pack1.createCompilationUnit("C.java", str, false, null);
+
+		String[] order= new String[] { "", "#" };
+		IChooseImportQuery query= createQuery("C", new String[] {}, new int[] {});
+
+		// A threshold of 2 would normally collapse the three java.util types into an on-demand import.
+		OrganizeImportsOperation op= createOperation(cu, order, 2, false, true, true, query);
+		setKeepExistingAndCollapse(cu.getJavaProject(), false, false);
+		op.run(null);
+
+		String expected= """
+			package pack1;
+
+			import java.util.Collection;
+			import java.util.Map;
+			import java.util.Set;
+
+			public class C {
+			    Collection<String> c;
+			    Map<String, String> m;
+			    Set<String> s;
+			}
+			""";
+		assertEqualString(cu.getSource(), expected);
+	}
+
 	@Test
 	public void test_PackageInfoBug157541a() throws Exception {
 		IPackageFragmentRoot sourceFolder= JavaProjectHelper.addSourceContainer(fJProject1, "src");
@@ -4085,4 +4202,10 @@ protected void setOrganizeImportSettings(String[] order, int threshold, int stat
 		}
 	}
 
+	protected void setKeepExistingAndCollapse(IJavaProject project, boolean keepExistingOnDemand, boolean collapseToOnDemand) {
+		IEclipsePreferences scope= new ProjectScope(project.getProject()).getNode(JavaUI.ID_PLUGIN);
+		scope.put(PreferenceConstants.ORGIMPORTS_KEEP_EXISTING_ONDEMAND, String.valueOf(keepExistingOnDemand));
+		scope.put(PreferenceConstants.ORGIMPORTS_COLLAPSE_TO_ONDEMAND, String.valueOf(collapseToOnDemand));
+	}
+
 }

org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/ImportOrganizeConfigurationBlock.java

@@ -73,13 +73,16 @@ public class ImportOrganizeConfigurationBlock extends OptionsConfigurationBlock
 	private static final Key PREF_ONDEMANDTHRESHOLD= getJDTUIKey(PreferenceConstants.ORGIMPORTS_ONDEMANDTHRESHOLD);
 	private static final Key PREF_IGNORELOWERCASE= getJDTUIKey(PreferenceConstants.ORGIMPORTS_IGNORELOWERCASE);
 	private static final Key PREF_STATICONDEMANDTHRESHOLD= getJDTUIKey(PreferenceConstants.ORGIMPORTS_STATIC_ONDEMANDTHRESHOLD);
+	private static final Key PREF_KEEP_EXISTING_ONDEMAND= getJDTUIKey(PreferenceConstants.ORGIMPORTS_KEEP_EXISTING_ONDEMAND);
+	private static final Key PREF_COLLAPSE_TO_ONDEMAND= getJDTUIKey(PreferenceConstants.ORGIMPORTS_COLLAPSE_TO_ONDEMAND);
 
 	private static final String DIALOGSETTING_LASTLOADPATH= JavaUI.ID_PLUGIN + ".importorder.loadpath"; //$NON-NLS-1$
 	private static final String DIALOGSETTING_LASTSAVEPATH= JavaUI.ID_PLUGIN + ".importorder.savepath"; //$NON-NLS-1$
 
 	private static Key[] getAllKeys() {
 		return new Key[] {
-			PREF_IMPORTORDER, PREF_ONDEMANDTHRESHOLD, PREF_STATICONDEMANDTHRESHOLD, PREF_IGNORELOWERCASE
+			PREF_IMPORTORDER, PREF_ONDEMANDTHRESHOLD, PREF_STATICONDEMANDTHRESHOLD, PREF_IGNORELOWERCASE,
+			PREF_KEEP_EXISTING_ONDEMAND, PREF_COLLAPSE_TO_ONDEMAND
 		};
 	}
 
@@ -177,6 +180,8 @@ public void doubleClicked(ListDialogField<ImportOrderEntry> field) {
 	private StringDialogField fThresholdField;
 	private StringDialogField fStaticThresholdField;
 	private SelectionButtonDialogField fIgnoreLowerCaseTypesField;
+	private SelectionButtonDialogField fKeepExistingOnDemandField;
+	private SelectionButtonDialogField fCollapseToOnDemandField;
 	private SelectionButtonDialogField fExportButton;
 	private SelectionButtonDialogField fImportButton;
 
@@ -226,6 +231,14 @@ public ImportOrganizeConfigurationBlock(IStatusChangeListener context, IProject
 		fIgnoreLowerCaseTypesField.setDialogFieldListener(adapter);
 		fIgnoreLowerCaseTypesField.setLabelText(PreferencesMessages.ImportOrganizeConfigurationBlock_ignoreLowerCase_label);
 
+		fKeepExistingOnDemandField= new SelectionButtonDialogField(SWT.CHECK);
+		fKeepExistingOnDemandField.setDialogFieldListener(adapter);
+		fKeepExistingOnDemandField.setLabelText(PreferencesMessages.ImportOrganizeConfigurationBlock_keepExistingOnDemand_label);
+
+		fCollapseToOnDemandField= new SelectionButtonDialogField(SWT.CHECK);
+		fCollapseToOnDemandField.setDialogFieldListener(adapter);
+		fCollapseToOnDemandField.setLabelText(PreferencesMessages.ImportOrganizeConfigurationBlock_collapseToOnDemand_label);
+
 		updateControls();
 	}
 
@@ -265,6 +278,8 @@ protected Control createContents(Composite parent) {
 		fThresholdField.doFillIntoGrid(composite, 2);
 		((GridData) fThresholdField.getTextControl(null).getLayoutData()).grabExcessHorizontalSpace= false;
 		fStaticThresholdField.doFillIntoGrid(composite, 2);
+		fCollapseToOnDemandField.doFillIntoGrid(composite, 2);
+		fKeepExistingOnDemandField.doFillIntoGrid(composite, 2);
 		fIgnoreLowerCaseTypesField.doFillIntoGrid(composite, 2);
 
 		Dialog.applyDialogFont(composite);
@@ -418,6 +433,8 @@ protected void updateControls() {
 		int threshold= getImportNumberThreshold(PREF_ONDEMANDTHRESHOLD);
 		int staticThreshold= getImportNumberThreshold(PREF_STATICONDEMANDTHRESHOLD);
 		boolean ignoreLowerCase= Boolean.parseBoolean(getValue(PREF_IGNORELOWERCASE));
+		boolean keepExistingOnDemand= Boolean.parseBoolean(getValue(PREF_KEEP_EXISTING_ONDEMAND));
+		boolean collapseToOnDemand= Boolean.parseBoolean(getValue(PREF_COLLAPSE_TO_ONDEMAND));
 
 		fOrderListField.removeAllElements();
 		for (ImportOrderEntry i : importOrder) {
@@ -426,6 +443,8 @@ protected void updateControls() {
 		fThresholdField.setText(String.valueOf(threshold));
 		fStaticThresholdField.setText(String.valueOf(staticThreshold));
 		fIgnoreLowerCaseTypesField.setSelection(ignoreLowerCase);
+		fKeepExistingOnDemandField.setSelection(keepExistingOnDemand);
+		fCollapseToOnDemandField.setSelection(collapseToOnDemand);
 	}
 
 
@@ -443,6 +462,10 @@ protected final void doDialogFieldChanged(DialogField field) {
 	  		}
 		} else if (field == fIgnoreLowerCaseTypesField) {
 	  		setValue(PREF_IGNORELOWERCASE, fIgnoreLowerCaseTypesField.isSelected());
+		} else if (field == fKeepExistingOnDemandField) {
+	  		setValue(PREF_KEEP_EXISTING_ONDEMAND, fKeepExistingOnDemandField.isSelected());
+		} else if (field == fCollapseToOnDemandField) {
+	  		setValue(PREF_COLLAPSE_TO_ONDEMAND, fCollapseToOnDemandField.isSelected());
 		} else if (field == fImportButton) {
 			List<ImportOrderEntry> order= loadImportOrder();
 			if (order != null) {

org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/PreferencesMessages.java

@@ -80,6 +80,8 @@ private PreferencesMessages() {
 	public static String ImportOrganizeConfigurationBlock_order_load_button;
 	public static String ImportOrganizeConfigurationBlock_order_save_button;
 	public static String ImportOrganizeConfigurationBlock_ignoreLowerCase_label;
+	public static String ImportOrganizeConfigurationBlock_keepExistingOnDemand_label;
+	public static String ImportOrganizeConfigurationBlock_collapseToOnDemand_label;
 	public static String ImportOrganizeConfigurationBlock_threshold_label;
 	public static String ImportOrganizeConfigurationBlock_error_invalidthreshold;
 	public static String ImportOrganizeConfigurationBlock_loadDialog_title;

org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/PreferencesMessages.properties

@@ -57,6 +57,8 @@ ImportOrganizeConfigurationBlock_order_add_static_button=New Stati&c...
 ImportOrganizeConfigurationBlock_order_load_button=I&mport...
 ImportOrganizeConfigurationBlock_order_save_button=E&xport...
 ImportOrganizeConfigurationBlock_ignoreLowerCase_label=Do not create imports for &types starting with a lowercase letter
+ImportOrganizeConfigurationBlock_keepExistingOnDemand_label=&Keep existing star (.*) imports
+ImportOrganizeConfigurationBlock_collapseToOnDemand_label=&Collapse single imports into star (.*) imports when the threshold is reached
 ImportOrganizeConfigurationBlock_threshold_label=Number of &imports needed for .* (e.g. 'org.eclipse.*'):
 ImportOrganizeConfigurationBlock_error_invalidthreshold=Invalid import number.
 ImportOrganizeConfigurationBlock_loadDialog_title=Load Import Order from File

org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/PreferenceConstants.java

@@ -360,7 +360,7 @@ private PreferenceConstants() {
 	 * <p>
 	 * Value is of type <code>Boolean</code>.
 	 * </p>
-	 * @since 3.36
+	 * @since 3.39
 	 */
 	public static final String CODEGEN_USE_MARKDOWN= CodeGenerationSettingsConstants.CODEGEN_USE_MARKDOWN;
 
@@ -456,6 +456,27 @@ private PreferenceConstants() {
 	 */
 	public static final String ORGIMPORTS_IGNORELOWERCASE= CodeGenerationSettingsConstants.ORGIMPORTS_IGNORELOWERCASE;
 
+	/**
+	 * A named preference that controls whether existing on-demand (".*") imports are preserved as
+	 * on-demand imports by the "Organize Imports" operation, instead of being expanded into single
+	 * imports.
+	 * <p>
+	 * Value is of type <code>Boolean</code>.
+	 * </p>
+	 * @since 3.39
+	 */
+	public static final String ORGIMPORTS_KEEP_EXISTING_ONDEMAND= CodeGenerationSettingsConstants.ORGIMPORTS_KEEP_EXISTING_ONDEMAND;
+
+	/**
+	 * A named preference that controls whether the "Organize Imports" operation may collapse single
+	 * imports into a new on-demand (".*") import once the on-demand threshold is reached.
+	 * <p>
+	 * Value is of type <code>Boolean</code>.
+	 * </p>
+	 * @since 3.39
+	 */
+	public static final String ORGIMPORTS_COLLAPSE_TO_ONDEMAND= CodeGenerationSettingsConstants.ORGIMPORTS_COLLAPSE_TO_ONDEMAND;
+
 	/**
 	 * A named preference that specifies whether children of a compilation unit are shown in the package explorer.
 	 * <p>
@@ -4140,6 +4161,8 @@ public static void initializeDefaultValues(IPreferenceStore store) {
 		store.setDefault(PreferenceConstants.ORGIMPORTS_ONDEMANDTHRESHOLD, 99);
 		store.setDefault(PreferenceConstants.ORGIMPORTS_STATIC_ONDEMANDTHRESHOLD, 99);
 		store.setDefault(PreferenceConstants.ORGIMPORTS_IGNORELOWERCASE, true);
+		store.setDefault(PreferenceConstants.ORGIMPORTS_KEEP_EXISTING_ONDEMAND, false);
+		store.setDefault(PreferenceConstants.ORGIMPORTS_COLLAPSE_TO_ONDEMAND, true);
 
 		// TypeFilterPreferencePage
 		store.setDefault(PreferenceConstants.TYPEFILTER_ENABLED, ""); //$NON-NLS-1$