diff --git a/src/main/java/cokr/xit/base/docs/xls/Format.java b/src/main/java/cokr/xit/base/docs/xls/Format.java
index 828a4c3..b44ebed 100644
--- a/src/main/java/cokr/xit/base/docs/xls/Format.java
+++ b/src/main/java/cokr/xit/base/docs/xls/Format.java
@@ -64,8 +64,7 @@ public class Format implements Convert.Support {
 			return convert.apply(obj);
 		}
 
-		if (key != null && obj instanceof Map) {
-			Map<?, ?> map = (Map<?, ?>)obj;
+		if (key != null && obj instanceof Map<?, ?> map) {
 			return map.get(key);
 		}
 
@@ -93,8 +92,7 @@ public class Format implements Convert.Support {
 			return false;
 		if (obj instanceof Style)
 			return false;
-		if (obj instanceof Format) {
-			Format format = (Format)obj;
+		if (obj instanceof Format format) {
 			return format.hasValue();
 		}
 		return true;
@@ -112,8 +110,7 @@ public class Format implements Convert.Support {
 			return null;
 		if (obj instanceof Style)
 			return null;
-		if (obj instanceof Format) {
-			Format format = (Format)obj;
+		if (obj instanceof Format format) {
 			if (format.key != null)
 				return format.key;
 			return null;
@@ -133,10 +130,10 @@ public class Format implements Convert.Support {
 	 * @return 현재 Format
 	 */
 	public Format style(Object obj) {
-		if (obj instanceof Style) {
-			cellStyle = cellStyle((Style)obj);
-		} else if (obj instanceof CellStyle) {
-			cellStyle = (CellStyle)obj;
+		if (obj instanceof Style style) {
+			cellStyle = cellStyle(style);
+		} else if (obj instanceof CellStyle style) {
+			cellStyle = style;
 		} else
 			throw new IllegalArgumentException("Unable to get a CellStyle from " + obj);
 
diff --git a/src/main/java/cokr/xit/base/docs/xls/XLSWriter.java b/src/main/java/cokr/xit/base/docs/xls/XLSWriter.java
index c3aa71c..b4f5016 100644
--- a/src/main/java/cokr/xit/base/docs/xls/XLSWriter.java
+++ b/src/main/java/cokr/xit/base/docs/xls/XLSWriter.java
@@ -86,8 +86,7 @@ public class XLSWriter extends XLS {
 		if (!isEmpty(t)) {
 			int c = cell.getColumnIndex();
 			if (isEmpty(objs)) {
-				if (t instanceof Map) {
-					Map<?, ?> map = (Map<?, ?>)t;
+				if (t instanceof Map<?, ?> map) {
 					objs = map.keySet().stream().map(v -> (Object)v).toList();
 				} else if (t instanceof Iterable) {
 					objs = (Iterable<Object>)t;
@@ -103,15 +102,15 @@ public class XLSWriter extends XLS {
 
 				Object val = null;
 				Format format = null;
-				if (obj instanceof Format)
-					format = (Format)obj;
+				if (obj instanceof Format fmt)
+					format = fmt;
 
 				if (format != null)
 					val = format.value(t);
 				else {
 					Object key = Format.getKey(obj);
-					if (key != null && t instanceof Map)
-						val = ((Map<?, ?>)t).get(key);
+					if (key != null && t instanceof Map<?, ?> map)
+						val = map.get(key);
 					else
 						val = obj;
 				}
@@ -253,18 +252,16 @@ public class XLSWriter extends XLS {
 	}
 
 	boolean setCellValue(Object val) {
-		if (val instanceof String) {
-			cell.setCellValue((String)val);
+		if (val instanceof String str) {
+			cell.setCellValue(str);
 			return true;
-		} else if (val instanceof Number) {
-			Number number = (Number)val;
+		} else if (val instanceof Number number) {
 			cell.setCellValue(number.doubleValue());
 			return true;
-		} else if (val instanceof Date) {
-			cell.setCellValue((Date)val);
+		} else if (val instanceof Date date) {
+			cell.setCellValue(date);
 			return true;
-		} else if (val instanceof Boolean) {
-			Boolean b = (Boolean)val;
+		} else if (val instanceof Boolean b) {
 			cell.setCellValue(b.booleanValue());
 			return true;
 		}
@@ -284,12 +281,12 @@ public class XLSWriter extends XLS {
 
 	void setCellStyle(Object obj) {
 		CellStyle cellStyle = null;
-		if (obj instanceof Format)
-			cellStyle = ((Format)obj).style();
-		else if (obj instanceof Style)
-			cellStyle = cellStyle((Style)obj);
-		else if (obj instanceof CellStyle)
-			cellStyle = (CellStyle)obj;
+		if (obj instanceof Format format)
+			cellStyle = format.style();
+		else if (obj instanceof Style style)
+			cellStyle = cellStyle(style);
+		else if (obj instanceof CellStyle style)
+			cellStyle = style;
 
 		if (cellStyle != null)
 			cell.setCellStyle(cellStyle);