Java tutorial
/* * Copyright (c) 2012, the Dart project authors. * * Licensed under the Eclipse Public License v1.0 (the "License"); you may not use this file except * in compliance with the License. You may obtain a copy of the License at * * http://www.eclipse.org/legal/epl-v10.html * * Unless required by applicable law or agreed to in writing, software distributed under the License * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express * or implied. See the License for the specific language governing permissions and limitations under * the License. */ package com.google.dart.tools.ui.internal.refactoring; import com.google.dart.tools.internal.corext.refactoring.code.ParameterInfo; import com.google.dart.tools.ui.internal.dialogs.TableTextCellEditor; import com.google.dart.tools.ui.internal.dialogs.TextFieldNavigationHandler; import com.google.dart.tools.ui.internal.refactoring.contentassist.VariableNamesProcessor; import com.google.dart.tools.ui.internal.util.ControlContentAssistHelper; import com.google.dart.tools.ui.internal.util.SWTUtil; import com.google.dart.tools.ui.internal.util.TableLayoutComposite; import org.eclipse.core.runtime.Assert; import org.eclipse.jface.contentassist.SubjectControlContentAssistant; import org.eclipse.jface.resource.JFaceResources; import org.eclipse.jface.viewers.ColumnWeightData; import org.eclipse.jface.viewers.ICellModifier; import org.eclipse.jface.viewers.ISelection; import org.eclipse.jface.viewers.ISelectionChangedListener; import org.eclipse.jface.viewers.IStructuredContentProvider; import org.eclipse.jface.viewers.IStructuredSelection; import org.eclipse.jface.viewers.ITableFontProvider; import org.eclipse.jface.viewers.ITableLabelProvider; import org.eclipse.jface.viewers.LabelProvider; import org.eclipse.jface.viewers.SelectionChangedEvent; import org.eclipse.jface.viewers.StructuredSelection; import org.eclipse.jface.viewers.TableViewer; import org.eclipse.jface.viewers.Viewer; import org.eclipse.swt.SWT; import org.eclipse.swt.events.KeyAdapter; import org.eclipse.swt.events.KeyEvent; import org.eclipse.swt.events.SelectionAdapter; import org.eclipse.swt.events.SelectionEvent; import org.eclipse.swt.events.TraverseEvent; import org.eclipse.swt.events.TraverseListener; import org.eclipse.swt.graphics.Font; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.widgets.Table; import org.eclipse.swt.widgets.TableColumn; import org.eclipse.swt.widgets.TableItem; import org.eclipse.swt.widgets.Text; import org.eclipse.ui.contentassist.ContentAssistHandler; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.Iterator; import java.util.List; /** * A special control to edit and reorder method parameters. */ @SuppressWarnings("deprecation") public class ChangeParametersControl extends Composite { public static class Mode { private final String fName; public static final Mode EXTRACT_METHOD = new Mode("EXTRACT_METHOD"); //$NON-NLS-1$ public static final Mode CHANGE_METHOD_SIGNATURE = new Mode("CHANGE_METHOD_SIGNATURE"); //$NON-NLS-1$ public static final Mode INTRODUCE_PARAMETER = new Mode("INTRODUCE_PARAMETER"); //$NON-NLS-1$ private Mode(String name) { fName = name; } public boolean canAddParameters() { return this == Mode.CHANGE_METHOD_SIGNATURE; } public boolean canChangeDefault() { return this == Mode.CHANGE_METHOD_SIGNATURE; } public boolean canChangeTypes() { return this == CHANGE_METHOD_SIGNATURE; } @Override public String toString() { return fName; } } private static class ParameterInfoContentProvider implements IStructuredContentProvider { @Override public void dispose() { // do nothing } @Override @SuppressWarnings("unchecked") public Object[] getElements(Object inputElement) { return removeMarkedAsDeleted((List<ParameterInfo>) inputElement); } @Override public void inputChanged(Viewer viewer, Object oldInput, Object newInput) { // do nothing } private ParameterInfo[] removeMarkedAsDeleted(List<ParameterInfo> paramInfos) { List<ParameterInfo> result = new ArrayList<ParameterInfo>(paramInfos.size()); for (Iterator<ParameterInfo> iter = paramInfos.iterator(); iter.hasNext();) { ParameterInfo info = iter.next(); if (!info.isDeleted()) { result.add(info); } } return result.toArray(new ParameterInfo[result.size()]); } } private static class ParameterInfoLabelProvider extends LabelProvider implements ITableLabelProvider, ITableFontProvider { @Override public Image getColumnImage(Object element, int columnIndex) { return null; } @Override public String getColumnText(Object element, int columnIndex) { ParameterInfo info = (ParameterInfo) element; switch (columnIndex) { case TYPE_PROP: return info.getNewTypeName(); case NEWNAME_PROP: return info.getNewName(); case DEFAULT_PROP: if (info.isAdded()) { return info.getDefaultValue(); } else { return "-"; //$NON-NLS-1$ } default: throw new IllegalArgumentException(columnIndex + ": " + element); //$NON-NLS-1$ } } @Override public Font getFont(Object element, int columnIndex) { ParameterInfo info = (ParameterInfo) element; if (info.isAdded()) { return JFaceResources.getFontRegistry().getBold(JFaceResources.DIALOG_FONT); } else { return null; } } } private class ParametersCellModifier implements ICellModifier { @Override public boolean canModify(Object element, String property) { Assert.isTrue(element instanceof ParameterInfo); if (property.equals(PROPERTIES[TYPE_PROP])) { return fMode.canChangeTypes(); } else if (property.equals(PROPERTIES[NEWNAME_PROP])) { return true; } else if (property.equals(PROPERTIES[DEFAULT_PROP])) { return (((ParameterInfo) element).isAdded()); } Assert.isTrue(false); return false; } @Override public Object getValue(Object element, String property) { Assert.isTrue(element instanceof ParameterInfo); if (property.equals(PROPERTIES[TYPE_PROP])) { return ((ParameterInfo) element).getNewTypeName(); } else if (property.equals(PROPERTIES[NEWNAME_PROP])) { return ((ParameterInfo) element).getNewName(); } else if (property.equals(PROPERTIES[DEFAULT_PROP])) { return ((ParameterInfo) element).getDefaultValue(); } Assert.isTrue(false); return null; } @Override public void modify(Object element, String property, Object value) { if (element instanceof TableItem) { element = ((TableItem) element).getData(); } if (!(element instanceof ParameterInfo)) { return; } boolean unchanged; ParameterInfo parameterInfo = (ParameterInfo) element; if (property.equals(PROPERTIES[NEWNAME_PROP])) { unchanged = parameterInfo.getNewName().equals(value); parameterInfo.setNewName((String) value); } else if (property.equals(PROPERTIES[DEFAULT_PROP])) { unchanged = parameterInfo.getDefaultValue().equals(value); parameterInfo.setDefaultValue((String) value); } else if (property.equals(PROPERTIES[TYPE_PROP])) { unchanged = parameterInfo.getNewTypeName().equals(value); parameterInfo.setNewTypeName((String) value); } else { throw new IllegalStateException(); } if (!unchanged) { ChangeParametersControl.this.fListener.parameterChanged(parameterInfo); ChangeParametersControl.this.fTableViewer.update(parameterInfo, new String[] { property }); } } } // TODO(scheglov) Should be top-level and have some functions private static class StubTypeContext { } private static final String[] PROPERTIES = { "type", "new", "default" }; //$NON-NLS-2$ //$NON-NLS-1$ //$NON-NLS-3$ private static final int TYPE_PROP = 0; private static final int NEWNAME_PROP = 1; private static final int DEFAULT_PROP = 2; private static final int ROW_COUNT = 7; private static void moveUp(List<ParameterInfo> elements, List<ParameterInfo> move) { List<ParameterInfo> res = new ArrayList<ParameterInfo>(elements.size()); List<ParameterInfo> deleted = new ArrayList<ParameterInfo>(); ParameterInfo floating = null; for (Iterator<ParameterInfo> iter = elements.iterator(); iter.hasNext();) { ParameterInfo curr = iter.next(); if (move.contains(curr)) { res.add(curr); } else if (curr.isDeleted()) { deleted.add(curr); } else { if (floating != null) { res.add(floating); } floating = curr; } } if (floating != null) { res.add(floating); } res.addAll(deleted); elements.clear(); for (Iterator<ParameterInfo> iter = res.iterator(); iter.hasNext();) { elements.add(iter.next()); } } private final Mode fMode; private final IParameterListChangeListener fListener; private List<ParameterInfo> fParameterInfos; // private final StubTypeContext fTypeContext; private final String[] fParamNameProposals; private ContentAssistHandler fNameContentAssistHandler; private TableViewer fTableViewer; private Button fUpButton; private Button fDownButton; private Button fEditButton; private Button fAddButton; private Button fRemoveButton; public ChangeParametersControl(Composite parent, int style, String label, IParameterListChangeListener listener, Mode mode) { this(parent, style, label, listener, mode, null, new String[0]); } public ChangeParametersControl(Composite parent, int style, String label, IParameterListChangeListener listener, Mode mode, String[] paramNameProposals) { this(parent, style, label, listener, mode, null, paramNameProposals); } public ChangeParametersControl(Composite parent, int style, String label, IParameterListChangeListener listener, Mode mode, StubTypeContext typeContext) { this(parent, style, label, listener, mode, typeContext, new String[0]); } /** * @param label the label before the table or <code>null</code> * @param typeContext the package in which to complete types */ private ChangeParametersControl(Composite parent, int style, String label, IParameterListChangeListener listener, Mode mode, StubTypeContext typeContext, String[] paramNameProposals) { super(parent, style); Assert.isNotNull(listener); fListener = listener; fMode = mode; // fTypeContext = typeContext; fParamNameProposals = paramNameProposals; GridLayout layout = new GridLayout(); layout.numColumns = 2; layout.marginWidth = 0; layout.marginHeight = 0; setLayout(layout); if (label != null) { Label tableLabel = new Label(this, SWT.NONE); GridData labelGd = new GridData(); labelGd.horizontalSpan = 2; tableLabel.setLayoutData(labelGd); tableLabel.setText(label); } createParameterList(this); createButtonComposite(this); } public void editParameter(ParameterInfo info) { fTableViewer.getControl().setFocus(); if (!info.isDeleted()) { fTableViewer.setSelection(new StructuredSelection(info), true); updateButtonsEnabledState(); editColumnOrNextPossible(NEWNAME_PROP); return; } } // ---- Parameter table ----------------------------------------------------------------------------------- public void setInput(List<ParameterInfo> parameterInfos) { Assert.isNotNull(parameterInfos); fParameterInfos = parameterInfos; fTableViewer.setInput(fParameterInfos); if (fParameterInfos.size() > 0) { fTableViewer.setSelection(new StructuredSelection(fParameterInfos.get(0))); } } private void addCellEditors() { fTableViewer.setColumnProperties(PROPERTIES); final TableTextCellEditor editors[] = new TableTextCellEditor[PROPERTIES.length]; editors[TYPE_PROP] = new TableTextCellEditor(fTableViewer, TYPE_PROP); editors[NEWNAME_PROP] = new TableTextCellEditor(fTableViewer, NEWNAME_PROP); editors[DEFAULT_PROP] = new TableTextCellEditor(fTableViewer, DEFAULT_PROP); if (fMode.canChangeTypes()) { // TODO(scheglov) // SubjectControlContentAssistant assistant = installParameterTypeContentAssist(editors[TYPE_PROP].getText()); // editors[TYPE_PROP].setContentAssistant(assistant); } if (fParamNameProposals.length > 0) { SubjectControlContentAssistant assistant = installParameterNameContentAssist( editors[NEWNAME_PROP].getText()); editors[NEWNAME_PROP].setContentAssistant(assistant); } for (int i = 0; i < editors.length; i++) { final int editorColumn = i; final TableTextCellEditor editor = editors[i]; // support tabbing between columns while editing: editor.getText().addTraverseListener(new TraverseListener() { @Override public void keyTraversed(TraverseEvent e) { switch (e.detail) { case SWT.TRAVERSE_TAB_NEXT: editColumnOrNextPossible(nextColumn(editorColumn)); e.detail = SWT.TRAVERSE_NONE; break; case SWT.TRAVERSE_TAB_PREVIOUS: editColumnOrPrevPossible(prevColumn(editorColumn)); e.detail = SWT.TRAVERSE_NONE; break; default: break; } } }); TextFieldNavigationHandler.install(editor.getText()); } editors[NEWNAME_PROP].setActivationListener(new TableTextCellEditor.IActivationListener() { @Override public void activate() { ParameterInfo[] selected = getSelectedElements(); if (selected.length == 1 && fNameContentAssistHandler != null) { fNameContentAssistHandler.setEnabled(selected[0].isAdded()); } } }); fTableViewer.setCellEditors(editors); fTableViewer.setCellModifier(new ParametersCellModifier()); } private void addColumnLayoutData(TableLayoutComposite layouter) { if (fMode.canChangeDefault()) { layouter.addColumnData(new ColumnWeightData(33, true)); layouter.addColumnData(new ColumnWeightData(33, true)); layouter.addColumnData(new ColumnWeightData(34, true)); } else { layouter.addColumnData(new ColumnWeightData(50, true)); layouter.addColumnData(new ColumnWeightData(50, true)); } } private void addSpacer(Composite parent) { Label label = new Label(parent, SWT.NONE); GridData gd = new GridData(GridData.FILL_HORIZONTAL); gd.heightHint = 5; label.setLayoutData(gd); } private boolean canMove(boolean up) { int notDeletedInfosCount = getNotDeletedInfosCount(); if (notDeletedInfosCount == 0) { return false; } int[] indc = getTable().getSelectionIndices(); if (indc.length == 0) { return false; } int invalid = up ? 0 : notDeletedInfosCount - 1; for (int i = 0; i < indc.length; i++) { if (indc[i] == invalid) { return false; } } return true; } private Button createAddButton(Composite buttonComposite) { Button button = new Button(buttonComposite, SWT.PUSH); button.setText(RefactoringMessages.ChangeParametersControl_buttons_add); button.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); SWTUtil.setButtonDimensionHint(button); // TODO(scheglov) not used in "Extract Method" // button.addSelectionListener(new SelectionAdapter() { // @Override // public void widgetSelected(SelectionEvent e) { // String[] excludedParamNames = new String[fParameterInfos.size()]; // for (int i = 0; i < fParameterInfos.size(); i++) { // ParameterInfo info = fParameterInfos.get(i); // excludedParamNames[i] = info.getNewName(); // } // IJavaProject javaProject = fTypeContext.getCuHandle().getJavaProject(); // String newParamName = StubUtility.suggestArgumentName( // javaProject, // RefactoringMessages.ChangeParametersControl_new_parameter_default_name, // excludedParamNames); // ParameterInfo newInfo = ParameterInfo.createInfoForAddedParameter( // "Object", newParamName, "null"); //$NON-NLS-1$ //$NON-NLS-2$ // int insertIndex = fParameterInfos.size(); // for (int i = fParameterInfos.size() - 1; i >= 0; i--) { // ParameterInfo info = fParameterInfos.get(i); // if (info.isNewVarargs()) { // insertIndex = i; // break; // } // } // fParameterInfos.add(insertIndex, newInfo); // fListener.parameterAdded(newInfo); // fTableViewer.refresh(); // fTableViewer.getControl().setFocus(); // fTableViewer.setSelection(new StructuredSelection(newInfo), true); // updateButtonsEnabledState(); // editColumnOrNextPossible(0); // } // }); return button; } private Button createButton(Composite buttonComposite, String text, final boolean up) { Button button = new Button(buttonComposite, SWT.PUSH); button.setText(text); button.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); SWTUtil.setButtonDimensionHint(button); button.addSelectionListener(new SelectionAdapter() { @Override public void widgetSelected(SelectionEvent e) { ISelection savedSelection = fTableViewer.getSelection(); if (savedSelection == null) { return; } ParameterInfo[] selection = getSelectedElements(); if (selection.length == 0) { return; } if (up) { moveUp(selection); } else { moveDown(selection); } fTableViewer.refresh(); fTableViewer.setSelection(savedSelection); fListener.parameterListChanged(); fTableViewer.getControl().setFocus(); } }); return button; } // ---- Button bar -------------------------------------------------------------------------------------- private void createButtonComposite(Composite parent) { Composite buttonComposite = new Composite(parent, SWT.NONE); buttonComposite.setLayoutData(new GridData(GridData.FILL_VERTICAL)); GridLayout gl = new GridLayout(); gl.marginHeight = 0; gl.marginWidth = 0; buttonComposite.setLayout(gl); if (fMode.canAddParameters()) { fAddButton = createAddButton(buttonComposite); } fEditButton = createEditButton(buttonComposite); if (fMode.canAddParameters()) { fRemoveButton = createRemoveButton(buttonComposite); } if (buttonComposite.getChildren().length != 0) { addSpacer(buttonComposite); } fUpButton = createButton(buttonComposite, RefactoringMessages.ChangeParametersControl_buttons_move_up, true); fDownButton = createButton(buttonComposite, RefactoringMessages.ChangeParametersControl_buttons_move_down, false); updateButtonsEnabledState(); } private Button createEditButton(Composite buttonComposite) { Button button = new Button(buttonComposite, SWT.PUSH); button.setText(RefactoringMessages.ChangeParametersControl_buttons_edit); button.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); SWTUtil.setButtonDimensionHint(button); // TODO(scheglov) // button.addSelectionListener(new SelectionAdapter() { // @Override // public void widgetSelected(SelectionEvent e) { // try { // ParameterInfo[] selected = getSelectedElements(); // Assert.isTrue(selected.length == 1); // ParameterInfo parameterInfo = selected[0]; // ParameterEditDialog dialog = new ParameterEditDialog( // getShell(), // parameterInfo, // fMode.canChangeTypes(), // fMode.canChangeDefault(), // fTypeContext); // dialog.open(); // fListener.parameterChanged(parameterInfo); // fTableViewer.update(parameterInfo, PROPERTIES); // } finally { // fTableViewer.getControl().setFocus(); // } // } // }); return button; } private void createParameterList(Composite parent) { TableLayoutComposite layouter = new TableLayoutComposite(parent, SWT.NONE); addColumnLayoutData(layouter); final Table table = new Table(layouter, SWT.MULTI | SWT.BORDER | SWT.FULL_SELECTION); table.setHeaderVisible(true); table.setLinesVisible(true); TableColumn tc; tc = new TableColumn(table, SWT.NONE, TYPE_PROP); tc.setResizable(true); tc.setText(RefactoringMessages.ChangeParametersControl_table_type); tc = new TableColumn(table, SWT.NONE, NEWNAME_PROP); tc.setResizable(true); tc.setText(RefactoringMessages.ChangeParametersControl_table_name); if (fMode.canChangeDefault()) { tc = new TableColumn(table, SWT.NONE, DEFAULT_PROP); tc.setResizable(true); tc.setText(RefactoringMessages.ChangeParametersControl_table_defaultValue); } GridData gd = new GridData(GridData.FILL_BOTH); gd.heightHint = SWTUtil.getTableHeightHint(table, ROW_COUNT); gd.widthHint = 40; layouter.setLayoutData(gd); fTableViewer = new TableViewer(table); fTableViewer.setUseHashlookup(true); fTableViewer.setContentProvider(new ParameterInfoContentProvider()); fTableViewer.setLabelProvider(new ParameterInfoLabelProvider()); fTableViewer.addSelectionChangedListener(new ISelectionChangedListener() { @Override public void selectionChanged(SelectionChangedEvent event) { updateButtonsEnabledState(); } }); table.addTraverseListener(new TraverseListener() { @Override public void keyTraversed(TraverseEvent e) { if (e.detail == SWT.TRAVERSE_RETURN && e.stateMask == SWT.NONE) { editColumnOrNextPossible(0); e.detail = SWT.TRAVERSE_NONE; } } }); table.addKeyListener(new KeyAdapter() { @Override public void keyPressed(KeyEvent e) { if (e.keyCode == SWT.F2 && e.stateMask == SWT.NONE) { editColumnOrNextPossible(0); e.doit = false; } } }); addCellEditors(); } private Button createRemoveButton(Composite buttonComposite) { final Button button = new Button(buttonComposite, SWT.PUSH); button.setText(RefactoringMessages.ChangeParametersControl_buttons_remove); button.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); SWTUtil.setButtonDimensionHint(button); // TODO(scheglov) // button.addSelectionListener(new SelectionAdapter() { // @Override // public void widgetSelected(SelectionEvent e) { // int index = getTable().getSelectionIndices()[0]; // ParameterInfo[] selected = getSelectedElements(); // for (int i = 0; i < selected.length; i++) { // if (selected[i].isAdded()) { // fParameterInfos.remove(selected[i]); // } else { // selected[i].markAsDeleted(); // } // } // restoreSelection(index); // } // // private void restoreSelection(int index) { // fTableViewer.refresh(); // fTableViewer.getControl().setFocus(); // int itemCount = getTableItemCount(); // if (itemCount != 0) { // if (index >= itemCount) { // index = itemCount - 1; // } // getTable().setSelection(index); // } // fListener.parameterListChanged(); // updateButtonsEnabledState(); // } // }); return button; } private void editColumnOrNextPossible(int column) { ParameterInfo[] selected = getSelectedElements(); if (selected.length != 1) { return; } int nextColumn = column; do { fTableViewer.editElement(selected[0], nextColumn); if (fTableViewer.isCellEditorActive()) { return; } nextColumn = nextColumn(nextColumn); } while (nextColumn != column); } private void editColumnOrPrevPossible(int column) { ParameterInfo[] selected = getSelectedElements(); if (selected.length != 1) { return; } int prevColumn = column; do { fTableViewer.editElement(selected[0], prevColumn); if (fTableViewer.isCellEditorActive()) { return; } prevColumn = prevColumn(prevColumn); } while (prevColumn != column); } private int getNotDeletedInfosCount() { if (fParameterInfos == null) { return 0; } int result = 0; for (Iterator<ParameterInfo> iter = fParameterInfos.iterator(); iter.hasNext();) { ParameterInfo info = iter.next(); if (!info.isDeleted()) { result++; } } return result; } private ParameterInfo[] getSelectedElements() { ISelection selection = fTableViewer.getSelection(); if (selection == null) { return new ParameterInfo[0]; } if (!(selection instanceof IStructuredSelection)) { return new ParameterInfo[0]; } List<?> selected = ((IStructuredSelection) selection).toList(); return selected.toArray(new ParameterInfo[selected.size()]); } private Table getTable() { return fTableViewer.getTable(); } // private int getTableItemCount() { // return getTable().getItemCount(); // } //---- editing ----------------------------------------------------------------------------------------------- private int getTableSelectionCount() { return getTable().getSelectionCount(); } private SubjectControlContentAssistant installParameterNameContentAssist(Text text) { VariableNamesProcessor processor = new VariableNamesProcessor(fParamNameProposals); SubjectControlContentAssistant contentAssistant = ControlContentAssistHelper .createJavaContentAssistant(processor); fNameContentAssistHandler = ContentAssistHandler.createHandlerForText(text, contentAssistant); return contentAssistant; } // TODO(scheglov) // private SubjectControlContentAssistant installParameterTypeContentAssist(Text text) { // DartTypeCompletionProcessor processor = new DartTypeCompletionProcessor(true, false); // if (fTypeContext == null) { // processor.setCompletionContext(null, null, null); // } else { // processor.setCompletionContext( // fTypeContext.getCuHandle(), // fTypeContext.getBeforeString(), // fTypeContext.getAfterString()); // } // SubjectControlContentAssistant contentAssistant = ControlContentAssistHelper.createJavaContentAssistant(processor); // ContentAssistHandler.createHandlerForText(text, contentAssistant); // return contentAssistant; // } //---- change order ---------------------------------------------------------------------------------------- private void moveDown(ParameterInfo[] selection) { Collections.reverse(fParameterInfos); moveUp(fParameterInfos, Arrays.asList(selection)); Collections.reverse(fParameterInfos); } private void moveUp(ParameterInfo[] selection) { moveUp(fParameterInfos, Arrays.asList(selection)); } private int nextColumn(int column) { return (column >= getTable().getColumnCount() - 1) ? 0 : column + 1; } private int prevColumn(int column) { return (column <= 0) ? getTable().getColumnCount() - 1 : column - 1; } private void updateButtonsEnabledState() { fUpButton.setEnabled(canMove(true)); fDownButton.setEnabled(canMove(false)); if (fEditButton != null) { fEditButton.setEnabled(getTableSelectionCount() == 1); } if (fAddButton != null) { fAddButton.setEnabled(true); } if (fRemoveButton != null) { fRemoveButton.setEnabled(getTableSelectionCount() != 0); } } }