diff --git a/TracerOnJavassist/src/tracer/OutputStatementsGenerator.java b/TracerOnJavassist/src/tracer/OutputStatementsGenerator.java
index 700afcc..12ef3d2 100644
--- a/TracerOnJavassist/src/tracer/OutputStatementsGenerator.java
+++ b/TracerOnJavassist/src/tracer/OutputStatementsGenerator.java
@@ -31,19 +31,26 @@
 		return generator;
 	}
 
-	public String generateReplaceStatementsForFieldSet(CtClass cc, FieldAccess f, int line) {
+	public String generateReplaceStatementsForFieldSet(CtClass cc, FieldAccess f, int line) throws NotFoundException {
 		String fieldName = "\"" + f.getClassName() + "." + f.getFieldName() + "\"";
 		String containerClass = "(($0 != null)?$0.getClass().getName():\"" + cc.getName() + "\")";
 		String containerObject = "(($0 != null)?System.identityHashCode($0):0)";
-		String valueClass = "(($1 != null)?$1.getClass().getName():\"---\")";
-		String valueObject = "(($1 != null)?System.identityHashCode($1):0)";
+		String valueClass;
+		String valueObject;
+		if (!f.getField().getType().isPrimitive()) {
+			valueClass = "(($1 != null)?$1.getClass().getName():\"---\")";
+			valueObject = "(($1 != null)?System.identityHashCode($1):0)";
+		} else {
+			valueClass = "\"" + f.getField().getType().getName() + "\"";		// ��{�^�̏ꍇ�AgetClass()�ł��Ȃ�����
+			valueObject = "$1";
+		}
 		String threadId = "Thread.currentThread().getId()";
 		String lineNum = "\"" + line + "\"";
 		String timeStamp = "System.nanoTime()";
 		return generator.generateReplaceStatementsForFieldSet(fieldName, containerClass, containerObject, valueClass, valueObject, threadId, lineNum, timeStamp);
 	}
 
-	public String generateReplaceStatementsForFieldGet(CtClass cc, CtBehavior m, FieldAccess f, int line) {
+	public String generateReplaceStatementsForFieldGet(CtClass cc, CtBehavior m, FieldAccess f, int line) throws NotFoundException {
 		String fieldName = "\"" + f.getClassName() + "." + f.getFieldName() + "\"";
 		String thisClass;
 		String thisObject;
@@ -57,8 +64,15 @@
 		}
 		String containerClass = "(($0 != null)?$0.getClass().getName():\"---\")";
 		String containerObject = "(($0 != null)?System.identityHashCode($0):0)";
-		String valueClass = "(($_ != null)?$_.getClass().getName():\"---\")";
-		String valueObject = "(($_ != null)?System.identityHashCode($_):0)";
+		String valueClass;
+		String valueObject;
+		if (!f.getField().getType().isPrimitive()) {
+			valueClass = "(($_ != null)?$_.getClass().getName():\"---\")";
+			valueObject = "(($_ != null)?System.identityHashCode($_):0)";
+		} else {
+			valueClass = "\"" + f.getField().getType().getName() + "\"";		// ��{�^�̏ꍇ�AgetClass()�ł��Ȃ�����
+			valueObject = "$_";
+		}
 		String threadId = "Thread.currentThread().getId()";
 		String lineNum = "\"" + line + "\"";
 		String timeStamp = "System.nanoTime()";
@@ -222,7 +236,7 @@
 					thisClass = "this.getClass().getName()"; 
 					thisObject = "System.identityHashCode(this)";
 				} else {
-					returnedClass = "\"" + ((CtMethod)m).getReturnType().getName() +"\"";
+					returnedClass = "\"" + ((CtMethod)m).getReturnType().getName() +"\"";		// ��{�^�̏ꍇ�AgetClass()�ł��Ȃ�����
 					returnedObject = "$_";
 					thisClass = "this.getClass().getName()"; 
 					thisObject = "System.identityHashCode(this)";
@@ -235,7 +249,7 @@
 					thisClass = "$0.getClass().getName()"; 
 					thisObject = "System.identityHashCode($0)";
 				} else {
-					returnedClass = "\"" + ((CtMethod)m).getReturnType().getName() +"\"";
+					returnedClass = "\"" + ((CtMethod)m).getReturnType().getName() +"\"";		// ��{�^�̏ꍇ�AgetClass()�ł��Ȃ�����
 					returnedObject = "$_";
 					thisClass = "$0.getClass().getName()"; 
 					thisObject = "System.identityHashCode($0)";