Mark org.eclipse.debug.ui as optional dependency

Debug.ui dependency is used only for showing dialog with all available
properties for convenient configuration of default repository folder.
This also makes creating standalone EGit client harder and increase its
weight.

This patch mark this dependency as optional and will hide 'Variable...'
button when StringVariableSelectionDialog class cannot be found on
classpath.

Change-Id: Ifea5bd8b94f948af8a93842d28f273a8aa89098a
Signed-off-by: Dariusz Luksza <dariusz@luksza.org>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

2 files changed, 20 insertions, 4 deletions

diff --git a/org.eclipse.egit.ui/META-INF/MANIFEST.MF b/org.eclipse.egit.ui/META-INF/MANIFEST.MF
index 7552b339d1..edeb538c0f 100644
--- a/org.eclipse.egit.ui/META-INF/MANIFEST.MF
+++ b/org.eclipse.egit.ui/META-INF/MANIFEST.MF
@@ -29,7 +29,7 @@ Require-Bundle: org.eclipse.core.runtime;bundle-version="[3.7.0,4.0.0)",
  org.eclipse.equinox.security;bundle-version="[1.0.0,2.0.0)",
  org.eclipse.help;bundle-version="[3.4.0,4.0.0)",
  org.eclipse.search;bundle-version="[3.4.0,4.0.0)";resolution:=optional,
- org.eclipse.debug.ui;bundle-version="[3.4.0,4.0.0)"
+ org.eclipse.debug.ui;bundle-version="[3.4.0,4.0.0)";resolution:=optional
 Bundle-ActivationPolicy: lazy
 Bundle-RequiredExecutionEnvironment: J2SE-1.5
 Import-Package: org.eclipse.egit.core;version="[2.3.0,2.4.0)",
diff --git a/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/preferences/GitPreferenceRoot.java b/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/preferences/GitPreferenceRoot.java
index ccdba0af35..666ce338d6 100644
--- a/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/preferences/GitPreferenceRoot.java
+++ b/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/preferences/GitPreferenceRoot.java
@@ -2,6 +2,7 @@
  * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
  * Copyright (C) 2010, Robin Rosenberg <robin.rosenberg@dewire.com>
  * Copyright (C) 2010, Mathias Kinzler <mathias.kinzler@sap.com>
+ * Copyright (C) 2013, Dariusz Luksza <dariusz.luksza@gmail.com>
  *
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
@@ -15,8 +16,6 @@ import java.io.File;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.variables.IStringVariableManager;
 import org.eclipse.core.variables.VariablesPlugin;
-
-import org.eclipse.debug.ui.StringVariableSelectionDialog;
 import org.eclipse.egit.ui.Activator;
 import org.eclipse.egit.ui.UIPreferences;
 import org.eclipse.egit.ui.UIText;
@@ -47,6 +46,8 @@ public class GitPreferenceRoot extends FieldEditorPreferencePage implements
 
 	private final static String[][] MERGE_MODE_NAMES_AND_VALUES = new String[3][2];
 
+	private final static boolean HAS_DEBUG_UI = hasDebugUiBundle();
+
 	static {
 		MERGE_MODE_NAMES_AND_VALUES[0][0] = UIText.GitPreferenceRoot_MergeMode_0_Label;
 		MERGE_MODE_NAMES_AND_VALUES[0][1] = "0";//$NON-NLS-1$
@@ -131,12 +132,18 @@ public class GitPreferenceRoot extends FieldEditorPreferencePage implements
 
 				super.createControl(parent);
 
+				if (HAS_DEBUG_UI)
+					addVariablesButton(parent);
+			}
+
+			private void addVariablesButton(Composite parent) {
 				Button variableButton = new Button(parent, SWT.PUSH);
 				variableButton.setText(UIText.GitPreferenceRoot_DefaultRepoFolderVariableButton);
 
 				variableButton.addSelectionListener(new SelectionAdapter() {
 					public void widgetSelected(SelectionEvent e) {
-						StringVariableSelectionDialog dialog = new StringVariableSelectionDialog(getShell());
+						org.eclipse.debug.ui.StringVariableSelectionDialog dialog = new org.eclipse.debug.ui.StringVariableSelectionDialog(
+								getShell());
 						int returnCode = dialog.open();
 						if (returnCode == Window.OK)
 							setStringValue(dialog.getVariableExpression());
@@ -215,4 +222,13 @@ public class GitPreferenceRoot extends FieldEditorPreferencePage implements
 		layout.marginWidth = 5;
 		layout.marginHeight = 5;
 	}
+
+	private static final boolean hasDebugUiBundle() {
+		try {
+			return Class
+					.forName("org.eclipse.debug.ui.StringVariableSelectionDialog") != null; //$NON-NLS-1$
+		} catch (ClassNotFoundException e) {
+			return false;
+		}
+	}
 }