diff --git a/src/org/ntlab/traceDebugger/DebuggingController.java b/src/org/ntlab/traceDebugger/DebuggingController.java
index 3b7145f..b9e72c1 100644
--- a/src/org/ntlab/traceDebugger/DebuggingController.java
+++ b/src/org/ntlab/traceDebugger/DebuggingController.java
@@ -1,7 +1,6 @@
 package org.ntlab.traceDebugger;
 
 import java.util.HashMap;
-import java.util.List;
 import java.util.Map;
 
 import org.eclipse.core.filebuffers.FileBuffers;
@@ -20,10 +19,6 @@
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.widgets.FileDialog;
 import org.eclipse.swt.widgets.Shell;
-import org.eclipse.ui.IViewPart;
-import org.eclipse.ui.IWorkbenchPage;
-import org.eclipse.ui.PartInitException;
-import org.eclipse.ui.PlatformUI;
 import org.ntlab.traceAnalysisPlatform.tracer.trace.ArrayUpdate;
 import org.ntlab.traceAnalysisPlatform.tracer.trace.BlockEnter;
 import org.ntlab.traceAnalysisPlatform.tracer.trace.FieldUpdate;
@@ -71,12 +66,8 @@
 		if (path == null) return false;
 		TraceJSON trace = new TraceJSON(path);
 		TraceDebuggerPlugin.setAnalyzer(new DeltaExtractionAnalyzer(trace));
-//		new VariableUpdatePointFinder(trace);
 		VariableUpdatePointFinder.getInstance().setTrace(trace);
 		traceBreakPoints.clear();
-//		((CallStackView)getOtherView(CallStackView.ID)).reset();
-//		((VariableView)getOtherView(VariableView.ID)).reset();
-//		((BreakPointView)getOtherView(BreakPointView.ID)).update(traceBreakPoints);		
 		((CallStackView)TraceDebuggerPlugin.getActiveView(CallStackView.ID)).reset();
 		((VariableView)TraceDebuggerPlugin.getActiveView(VariableView.ID)).reset();
 		((BreakPointView)TraceDebuggerPlugin.getActiveView(BreakPointView.ID)).update(traceBreakPoints);
@@ -110,7 +101,6 @@
 			MessageDialog.openInformation(null, "Error", "This trace point does not exist in the trace.");
 			return false;
 		}
-//		((BreakPointView)getOtherView(BreakPointView.ID)).update(traceBreakPoints);
 		((BreakPointView)TraceDebuggerPlugin.getActiveView(BreakPointView.ID)).update(traceBreakPoints);
 		return true;
 	}
@@ -118,7 +108,6 @@
 	public boolean removeTraceBreakPointAction() {
 		if (selectedTraceBreakPoint == null) return false;
 		traceBreakPoints.removeTraceBreakPoint(selectedTraceBreakPoint);
-//		((BreakPointView)getOtherView(BreakPointView.ID)).update(traceBreakPoints);
 		((BreakPointView)TraceDebuggerPlugin.getActiveView(BreakPointView.ID)).update(traceBreakPoints);
 		return true;
 	}
@@ -126,7 +115,6 @@
 	public boolean changeAvailableAction() {
 		if (selectedTraceBreakPoint == null) return false;
 		selectedTraceBreakPoint.changeAvailable();
-//		((BreakPointView)getOtherView(BreakPointView.ID)).update(traceBreakPoints);
 		((BreakPointView)TraceDebuggerPlugin.getActiveView(BreakPointView.ID)).update(traceBreakPoints);
 		return true;
 	}
@@ -153,8 +141,6 @@
 				e.printStackTrace();
 			}			
 		}
-//		((CallStackView)getOtherView(CallStackView.ID)).reset();
-//		((VariableView)getOtherView(VariableView.ID)).reset();
 		((CallStackView)TraceDebuggerPlugin.getActiveView(CallStackView.ID)).reset();
 		((VariableView)TraceDebuggerPlugin.getActiveView(VariableView.ID)).reset();
 	}
@@ -190,16 +176,19 @@
 			previousTp = debuggingTp.duplicate();
 		}
 		TracePoint goalTp = debuggingTp.duplicate();
-		
-		// �X�e�b�v�t����p���č��x�͌Ăяo����ɂ�����Ȃ���\�ߌ��‚��Ă��������B�_�܂Ői�܂��� (�ϐ������X�V�̂��ߓr���̃A�b�v�f�[�g��S�ďE��)
-		debuggingTp = startTp;
-		do {
-			Statement statement = debuggingTp.getStatement();
-			if (statement.equals(goalTp.getStatement())) break;
-			if (statement instanceof FieldUpdate || statement instanceof ArrayUpdate) {
-				Variables.getInstance().addDifferentialUpdatePoint(debuggingTp);
-			}
-		} while (debuggingTp.stepFull());
+		if (!isReturned) {
+			// �X�e�b�v�t����p���č��x�͌Ăяo����ɂ�����Ȃ���\�ߌ��‚��Ă��������B�_�܂Ői�܂��� (�ϐ������X�V�̂��ߓr���̃A�b�v�f�[�g��S�ďE��)
+			debuggingTp = startTp;
+			do {
+				Statement statement = debuggingTp.getStatement();
+				if (statement.equals(goalTp.getStatement())) break;
+				if (statement instanceof FieldUpdate || statement instanceof ArrayUpdate) {
+					Variables.getInstance().addDifferentialUpdatePoint(debuggingTp);
+				}
+			} while (debuggingTp.stepFull());			
+		} else {
+			debuggingTp = goalTp;
+		}
 
 		if (!debuggingTp.isValid()) {
 			terminateAction();
@@ -232,18 +221,22 @@
 		TracePoint previousTp = debuggingTp;
 		debuggingTp = debuggingTp.duplicate();
 		TracePoint startTp = debuggingTp.duplicate();
-		debuggingTp.stepNext();
+		boolean isReturned = !(debuggingTp.stepNext());
 		TracePoint goalTp = debuggingTp.duplicate();
-		
-		// �X�e�b�v�t����p���č��x�͌Ăяo����ɂ�����Ȃ���\�ߌ��‚��Ă��������B�_�܂Ői�܂��� (�ϐ������X�V�̂��ߓr���̃A�b�v�f�[�g��S�ďE��)
-		debuggingTp = startTp;
-		do {
-			Statement statement = debuggingTp.getStatement();
-			if (statement.equals(goalTp.getStatement())) break;
-			if (statement instanceof FieldUpdate || statement instanceof ArrayUpdate) {
-				Variables.getInstance().addDifferentialUpdatePoint(debuggingTp);
-			}
-		} while (debuggingTp.stepFull());
+		if (!isReturned) {
+			// �X�e�b�v�t����p���č��x�͌Ăяo����ɂ�����Ȃ���\�ߌ��‚��Ă��������B�_�܂Ői�܂��� (�ϐ������X�V�̂��ߓr���̃A�b�v�f�[�g��S�ďE��)
+			debuggingTp = startTp;
+			do {
+				Statement statement = debuggingTp.getStatement();
+				if (statement.equals(goalTp.getStatement())) break;
+				if (statement instanceof FieldUpdate || statement instanceof ArrayUpdate) {
+					Variables.getInstance().addDifferentialUpdatePoint(debuggingTp);
+				}
+			} while (debuggingTp.stepFull());			
+		} else {
+			debuggingTp = startTp;
+			startTp.stepOver();
+		}
 
 		if (!debuggingTp.isValid()) {
 			terminateAction();
@@ -253,7 +246,6 @@
 		if (debuggingTp.getStatement() instanceof BlockEnter) {
 			debuggingTp.stepFull();
 		}
-		boolean isReturned = false;
 		refresh(previousTp, debuggingTp, isReturned, true);
 		return true;	
 	}
@@ -351,13 +343,10 @@
 	private void refresh(TracePoint from, TracePoint to, boolean isReturned, boolean canDifferentialUpdateVariables) {
 		MethodExecution me = to.getMethodExecution();
 		int lineNo = to.getStatement().getLineNo();
-//		JavaEditorOperator.openSrcFileOfMethodExecution(me, lineNo);
 		IMarker marker = createCurrentLineMarker(me, lineNo);
 		JavaEditorOperator.markAndOpenJavaFile(marker);
-//		CallStackView callStackView = ((CallStackView)getOtherView(CallStackView.ID));
 		CallStackView callStackView = ((CallStackView)TraceDebuggerPlugin.getActiveView(CallStackView.ID));
 		callStackView.updateByTracePoint(to);
-//		VariableView variableView = ((VariableView)getOtherView(VariableView.ID));
 		VariableView variableView = ((VariableView)TraceDebuggerPlugin.getActiveView(VariableView.ID));
 		if (!isReturned && canDifferentialUpdateVariables) {
 //			variableView.updateVariablesByTracePoint(from, to, isReturned);
@@ -387,7 +376,6 @@
 	public IMarker createCurrentLineMarker(MethodExecution methodExecution, int highlightLineNo) {
 		IFile file = JavaElementFinder.findIFile(methodExecution);
 		try {
-//			file.deleteMarkers(CURRENT_MARKER_ID, false, IResource.DEPTH_ZERO);
 			if (currentLineMarker != null) currentLineMarker.delete();
 			currentLineMarker = file.createMarker(CURRENT_MARKER_ID);
 			Map<String, Object> attributes = new HashMap<>();
@@ -411,14 +399,5 @@
 			e.printStackTrace();
 		}
 		return currentLineMarker;
-	}
-	
-//	private IViewPart getOtherView(String viewId) {
-//		IWorkbenchPage workbenchPage = PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage();
-//		try {
-//			return workbenchPage.showView(viewId);
-//		} catch (PartInitException e) {
-//			throw new RuntimeException(e);
-//		}
-//	}
+	}	
 }