diff --git a/TracerOnJavassist/src/tracer/ITraceGenerator.java b/TracerOnJavassist/src/tracer/ITraceGenerator.java
new file mode 100644
index 0000000..870078d
--- /dev/null
+++ b/TracerOnJavassist/src/tracer/ITraceGenerator.java
@@ -0,0 +1,34 @@
+package tracer;
+
+import javassist.CtBehavior;
+import javassist.CtClass;
+
+/**
+ * �g���[�X�o�͂��s�����s��������̃t�H�[�}�b�g�ˑ�����
+ * @author Nitta
+ *
+ */
+public interface ITraceGenerator {
+
+	public abstract String generateReplaceStatementsForFieldSet(
+			String targetClass, String targetObject, 
+			String argClass, String argObject, 
+			String threadId, String timeStamp);
+
+	public abstract String generateReplaceStatementsForFieldGet(String thisClass, String thisObject, 
+			String targetClass, String targetObject,
+			String returnedClass, String returnedObject, 
+			String threadId, String timeStamp);
+
+	public abstract String generateInsertBeforeStatements(
+			CtBehavior m, String methodSignature,
+			String thisClass, String thisObject, CtClass[] parameterClasses,
+			String threadId, String timeStamp);
+
+	public abstract String generateInsertAfterStatements(
+			CtClass cls, CtBehavior m,
+			String thisObject, 
+			String returnedClass, String returnedObject,
+			String threadId, String timeStamp,
+			boolean isCallerSideInstrumentation);
+}