diff --git a/README.md b/README.md
index 25750de..6e898ef 100644
--- a/README.md
+++ b/README.md
@@ -105,7 +105,7 @@ List<Product> products = Arrays.asList(
 );
 
 // 3. Export to Excel
-ExcelExporter<Product> exporter = ExcelExporter.builder(Product.class, products)
+DefaultExcelExporter<Product> exporter = DefaultExcelExporter.builder(Product.class, products)
     .sheetStrategy(SheetStrategy.MULTI_SHEET) // Optional, MULTI_SHEET is default
     .maxRows(100)   // Optional, Max row of SpreadsheetVersion.EXCEL2007 is default
     .sheetName("Products") // Optional, if not specified sheets will be named Sheet0, Sheet1, etc.
diff --git a/build.gradle b/build.gradle
index a4b845b..3cc273b 100644
--- a/build.gradle
+++ b/build.gradle
@@ -19,7 +19,7 @@ repositories {
 
 java {
     toolchain {
-        languageVersion = JavaLanguageVersion.of(23)
+        languageVersion = JavaLanguageVersion.of(21)
     }
     withSourcesJar() // 소스 코드도 포함
 }
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 9355b41..ca025c8 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.10-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.14-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
diff --git a/src/main/java/io/github/hee9841/excel/annotation/Excel.java b/src/main/java/io/github/hee9841/excel/annotation/Excel.java
index ea79191..e4adf85 100644
--- a/src/main/java/io/github/hee9841/excel/annotation/Excel.java
+++ b/src/main/java/io/github/hee9841/excel/annotation/Excel.java
@@ -41,7 +41,7 @@
  * 
  * // Usage example:
  * List{@literal <}UserData{@literal >} users = getUserData();
- * ExcelExporter{@literal <}UserData{@literal >} exporter = ExcelExporter.builder(UserData.class, users)
+ * DefaultExcelExporter{@literal <}UserData{@literal >} exporter = DefaultExcelExporter.builder(UserData.class, users)
  *     .sheetName("Users")
  *     .build();
  * exporter.write(new FileOutputStream("users.xlsx"));
diff --git a/src/main/java/io/github/hee9841/excel/annotation/ExcelColumn.java b/src/main/java/io/github/hee9841/excel/annotation/ExcelColumn.java
index d1ee435..70b0feb 100644
--- a/src/main/java/io/github/hee9841/excel/annotation/ExcelColumn.java
+++ b/src/main/java/io/github/hee9841/excel/annotation/ExcelColumn.java
@@ -1,7 +1,7 @@
 package io.github.hee9841.excel.annotation;
 
 import io.github.hee9841.excel.format.CellFormats;
-import io.github.hee9841.excel.meta.ColumnDataType;
+import io.github.hee9841.excel.core.meta.ColumnDataType;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
diff --git a/src/main/java/io/github/hee9841/excel/core/ExcelExporter.java b/src/main/java/io/github/hee9841/excel/core/exporter/DefaultExcelExporter.java
similarity index 88%
rename from src/main/java/io/github/hee9841/excel/core/ExcelExporter.java
rename to src/main/java/io/github/hee9841/excel/core/exporter/DefaultExcelExporter.java
index bacaaff..a75fe65 100644
--- a/src/main/java/io/github/hee9841/excel/core/ExcelExporter.java
+++ b/src/main/java/io/github/hee9841/excel/core/exporter/DefaultExcelExporter.java
@@ -1,4 +1,4 @@
-package io.github.hee9841.excel.core;
+package io.github.hee9841.excel.core.exporter;
 
 import io.github.hee9841.excel.exception.ExcelException;
 import io.github.hee9841.excel.strategy.SheetStrategy;
@@ -6,26 +6,26 @@
 import java.util.List;
 
 /**
- * ExcelExporter is a concrete implementation of {@link SXSSFExcelFile} that provides functionality
+ * DefaultExcelExporter is a concrete implementation of {@link SXSSFExporter} that provides functionality
  * for exporting data to Excel files. This class uses the SXSSFWorkbook from Apache POI for
  * efficient
  * handling of large datasets by streaming data to disk.
  *
- * <p>The ExcelExporter supports two sheet management strategies:</p>
+ * <p>The DefaultExcelExporter supports two sheet management strategies:</p>
  * <ul>
  *     <li>ONE_SHEET - All data is exported to a single sheet (limited by max rows per sheet)</li>
  *     <li>MULTI_SHEET - Data is split across multiple sheets when exceeding max rows per sheet</li>
  * </ul>
  *
- * <p>Use the {@link ExcelExporterBuilder} to configure and instantiate this class.</p>
+ * <p>Use the {@link DefaultExcelExporterBuilder} to configure and instantiate this class.</p>
  *
  * @param <T> The type of data to be exported to Excel. The type must be annotated appropriately
  *            for Excel column mapping using the library's annotation system.
- * @see SXSSFExcelFile
- * @see ExcelExporterBuilder
+ * @see SXSSFExporter
+ * @see DefaultExcelExporterBuilder
  * @see SheetStrategy
  */
-public class ExcelExporter<T> extends SXSSFExcelFile<T> {
+public class DefaultExcelExporter<T> extends SXSSFExporter<T> {
 
     private static final String EXCEED_MAX_ROW_MSG_2ARGS =
         "The data size exceeds the maximum number of rows allowed per sheet. "
@@ -44,10 +44,10 @@ public class ExcelExporter<T> extends SXSSFExcelFile<T> {
 
 
     /**
-     * Constructs an ExcelExporter with the specified configuration.
+     * Constructs an DefaultExcelExporter with the specified configuration.
      *
-     * <p>This constructor is not meant to be called directly. Use {@link ExcelExporterBuilder}
-     * to create instances of ExcelExporter.</p>
+     * <p>This constructor is not meant to be called directly. Use {@link DefaultExcelExporterBuilder}
+     * to create instances of DefaultExcelExporter.</p>
      *
      * @param type            The class type of the data to be exported
      * @param data            The list of data objects to be exported
@@ -55,7 +55,7 @@ public class ExcelExporter<T> extends SXSSFExcelFile<T> {
      * @param sheetName       Base name for sheets (null for default names)
      * @param maxRowsPerSheet Maximum number of rows allowed per sheet
      */
-    ExcelExporter(
+    DefaultExcelExporter(
         Class<T> type,
         List<T> data,
         SheetStrategy sheetStrategy,
@@ -74,15 +74,15 @@ public class ExcelExporter<T> extends SXSSFExcelFile<T> {
 
 
     /**
-     * Creates a new builder for configuring and instantiating an ExcelExporter.
+     * Creates a new builder for configuring and instantiating an DefaultExcelExporter.
      *
      * @param <T>  The type of data to be exported
      * @param type The class of the data type
      * @param data The list of data objects to be exported
-     * @return A new ExcelExporterBuilder instance
+     * @return A new DefaultExcelExporterBuilder instance
      */
-    public static <T> ExcelExporterBuilder<T> builder(Class<T> type, List<T> data) {
-        return new ExcelExporterBuilder<>(type, data, supplyExcelVersion.getMaxRows());
+    public static <T> DefaultExcelExporterBuilder<T> builder(Class<T> type, List<T> data) {
+        return new DefaultExcelExporterBuilder<>(type, data, supplyExcelVersion.getMaxRows());
     }
 
 
diff --git a/src/main/java/io/github/hee9841/excel/core/ExcelExporterBuilder.java b/src/main/java/io/github/hee9841/excel/core/exporter/DefaultExcelExporterBuilder.java
similarity index 78%
rename from src/main/java/io/github/hee9841/excel/core/ExcelExporterBuilder.java
rename to src/main/java/io/github/hee9841/excel/core/exporter/DefaultExcelExporterBuilder.java
index bcb8b2e..c9519cf 100644
--- a/src/main/java/io/github/hee9841/excel/core/ExcelExporterBuilder.java
+++ b/src/main/java/io/github/hee9841/excel/core/exporter/DefaultExcelExporterBuilder.java
@@ -1,11 +1,11 @@
-package io.github.hee9841.excel.core;
+package io.github.hee9841.excel.core.exporter;
 
 import io.github.hee9841.excel.exception.ExcelException;
 import io.github.hee9841.excel.strategy.SheetStrategy;
 import java.util.List;
 
 /**
- * Builder class for creating and configuring {@link ExcelExporter} instances.
+ * Builder class for creating and configuring {@link DefaultExcelExporter} instances.
  * This class implements the Builder pattern to provide a fluent interface for
  * configuring Excel export settings.
  *
@@ -18,7 +18,7 @@
  *
  * <p>Example usage:</p>
  * <pre>
- * ExcelExporter&lt;MyData&gt; exporter = ExcelExporter.builder(MyData.class, dataList)
+ * DefaultExcelExporter&lt;MyData&gt; exporter = DefaultExcelExporter.builder(MyData.class, dataList)
  *     .sheetStrategy(SheetStrategy.ONE_SHEET)
  *     .maxRows(10000)
  *     .sheetName("MySheet")
@@ -27,7 +27,7 @@
  *
  * @param <T> The type of data to be exported
  */
-public class ExcelExporterBuilder<T> {
+public class DefaultExcelExporterBuilder<T> {
 
     private final Class<T> type;
     private final List<T> data;
@@ -39,13 +39,13 @@ public class ExcelExporterBuilder<T> {
     private String sheetName;
 
     /**
-     * Constructs a new ExcelExporterBuilder with the specified type and data.
+     * Constructs a new DefaultExcelExporterBuilder with the specified type and data.
      *
      * @param type               The class type of the data to be exported
      * @param data               The list of data objects to be exported
      * @param supplyExcelMaxRows The maximum number of rows supported by the Excel version
      */
-    ExcelExporterBuilder(
+    DefaultExcelExporterBuilder(
         Class<T> type,
         List<T> data,
         int supplyExcelMaxRows
@@ -64,7 +64,7 @@ public class ExcelExporterBuilder<T> {
      * @param sheetStrategy The strategy to use for sheet management (ONE_SHEET or MULTI_SHEET)
      * @return This builder instance for method chaining
      */
-    public ExcelExporterBuilder<T> sheetStrategy(SheetStrategy sheetStrategy) {
+    public DefaultExcelExporterBuilder<T> sheetStrategy(SheetStrategy sheetStrategy) {
         this.sheetStrategy = sheetStrategy;
         return this;
     }
@@ -76,7 +76,7 @@ public ExcelExporterBuilder<T> sheetStrategy(SheetStrategy sheetStrategy) {
      * @return This builder instance for method chaining
      * @throws ExcelException if maxRowsPerSheet exceeds the Excel version's maximum row limit
      */
-    public ExcelExporterBuilder<T> maxRows(int maxRowsPerSheet) {
+    public DefaultExcelExporterBuilder<T> maxRows(int maxRowsPerSheet) {
         if (maxRowsPerSheet > supplyExcelMaxRows) {
             throw new ExcelException(String.format(
                 "The maximum rows per sheet(%d) cannot exceed the supplied Excel sheet version's maximum row limit(%d).",
@@ -99,18 +99,18 @@ public ExcelExporterBuilder<T> maxRows(int maxRowsPerSheet) {
      * @param sheetName The base name for sheets
      * @return This builder instance for method chaining
      */
-    public ExcelExporterBuilder<T> sheetName(String sheetName) {
+    public DefaultExcelExporterBuilder<T> sheetName(String sheetName) {
         this.sheetName = sheetName;
         return this;
     }
 
     /**
-     * Builds and returns a new ExcelExporter instance with the configured settings.
+     * Builds and returns a new DefaultExcelExporter instance with the configured settings.
      *
-     * @return A new ExcelExporter instance
+     * @return A new DefaultExcelExporter instance
      */
-    public ExcelExporter<T> build() {
-        return new ExcelExporter<T>(
+    public DefaultExcelExporter<T> build() {
+        return new DefaultExcelExporter<T>(
             this.type,
             this.data,
             this.sheetStrategy,
diff --git a/src/main/java/io/github/hee9841/excel/core/ExcelFile.java b/src/main/java/io/github/hee9841/excel/core/exporter/ExcelExporter.java
similarity index 91%
rename from src/main/java/io/github/hee9841/excel/core/ExcelFile.java
rename to src/main/java/io/github/hee9841/excel/core/exporter/ExcelExporter.java
index 676db1e..30903d5 100644
--- a/src/main/java/io/github/hee9841/excel/core/ExcelFile.java
+++ b/src/main/java/io/github/hee9841/excel/core/exporter/ExcelExporter.java
@@ -1,4 +1,4 @@
-package io.github.hee9841.excel.core;
+package io.github.hee9841.excel.core.exporter;
 
 import java.io.IOException;
 import java.io.OutputStream;
@@ -16,7 +16,7 @@
  *
  * @param <T> The type of data to be handled in the Excel file
  */
-public interface ExcelFile<T> {
+public interface ExcelExporter<T> {
 
     /**
      * Writes the Excel file content to the specified output stream.
diff --git a/src/main/java/io/github/hee9841/excel/core/SXSSFExcelFile.java b/src/main/java/io/github/hee9841/excel/core/exporter/SXSSFExporter.java
similarity index 94%
rename from src/main/java/io/github/hee9841/excel/core/SXSSFExcelFile.java
rename to src/main/java/io/github/hee9841/excel/core/exporter/SXSSFExporter.java
index d7aecda..3b6c0d1 100644
--- a/src/main/java/io/github/hee9841/excel/core/SXSSFExcelFile.java
+++ b/src/main/java/io/github/hee9841/excel/core/exporter/SXSSFExporter.java
@@ -1,8 +1,8 @@
-package io.github.hee9841.excel.core;
+package io.github.hee9841.excel.core.exporter;
 
 import io.github.hee9841.excel.exception.ExcelException;
-import io.github.hee9841.excel.meta.ColumnInfo;
-import io.github.hee9841.excel.meta.ColumnInfoMapper;
+import io.github.hee9841.excel.core.meta.ColumnInfo;
+import io.github.hee9841.excel.core.meta.ColumnInfoMapper;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.lang.reflect.Field;
@@ -36,9 +36,9 @@
  *
  * @param <T> The type of data to be handled in the Excel file
  */
-public abstract class SXSSFExcelFile<T> implements ExcelFile<T> {
+public abstract class SXSSFExporter<T> implements ExcelExporter<T> {
 
-    protected static final Logger logger = LoggerFactory.getLogger(SXSSFExcelFile.class);
+    protected static final Logger logger = LoggerFactory.getLogger(SXSSFExporter.class);
 
     protected static final SpreadsheetVersion supplyExcelVersion = SpreadsheetVersion.EXCEL2007;
 
@@ -49,9 +49,9 @@ public abstract class SXSSFExcelFile<T> implements ExcelFile<T> {
     protected String dtoTypeName;
 
     /**
-     * Constructs a new SXSSFExcelFile with a new SXSSFWorkbook instance.
+     * Constructs a new SXSSFExporter with a new SXSSFWorkbook instance.
      */
-    protected SXSSFExcelFile() {
+    protected SXSSFExporter() {
         this.workbook = new SXSSFWorkbook();
     }
 
diff --git a/src/main/java/io/github/hee9841/excel/meta/ColumnDataType.java b/src/main/java/io/github/hee9841/excel/core/meta/ColumnDataType.java
similarity index 99%
rename from src/main/java/io/github/hee9841/excel/meta/ColumnDataType.java
rename to src/main/java/io/github/hee9841/excel/core/meta/ColumnDataType.java
index 6b0d000..a614757 100644
--- a/src/main/java/io/github/hee9841/excel/meta/ColumnDataType.java
+++ b/src/main/java/io/github/hee9841/excel/core/meta/ColumnDataType.java
@@ -1,4 +1,4 @@
-package io.github.hee9841.excel.meta;
+package io.github.hee9841.excel.core.meta;
 
 import io.github.hee9841.excel.annotation.ExcelColumnStyle;
 import io.github.hee9841.excel.exception.ExcelException;
@@ -30,10 +30,12 @@ public enum ColumnDataType {
      * Automatically determine the cell type based on the field type
      */
     AUTO,
+
     /**
      * No specific cell type (default)
      */
     _NONE,
+
     /**
      * Numeric cell type for various number formats
      */
@@ -50,6 +52,7 @@ public enum ColumnDataType {
         CellFormats._NONE,
         true
     ),
+
     /**
      * Boolean cell type
      */
@@ -61,6 +64,7 @@ public enum ColumnDataType {
         CellFormats._NONE,
         true
     ),
+
     /**
      * String cell type for text values
      */
@@ -72,6 +76,7 @@ public enum ColumnDataType {
         CellFormats._NONE,
         true
     ),
+
     /**
      * Enum cell type - uses toString() to get the value
      */
@@ -81,6 +86,7 @@ public enum ColumnDataType {
         CellFormats._NONE,
         true
     ),
+
     /**
      * Formula cell type - value is treated as an Excel formula
      */
diff --git a/src/main/java/io/github/hee9841/excel/meta/ColumnInfo.java b/src/main/java/io/github/hee9841/excel/core/meta/ColumnInfo.java
similarity index 98%
rename from src/main/java/io/github/hee9841/excel/meta/ColumnInfo.java
rename to src/main/java/io/github/hee9841/excel/core/meta/ColumnInfo.java
index 8329fb2..179cd4b 100644
--- a/src/main/java/io/github/hee9841/excel/meta/ColumnInfo.java
+++ b/src/main/java/io/github/hee9841/excel/core/meta/ColumnInfo.java
@@ -1,4 +1,4 @@
-package io.github.hee9841.excel.meta;
+package io.github.hee9841.excel.core.meta;
 
 import io.github.hee9841.excel.annotation.ExcelColumnStyle;
 import org.apache.poi.ss.usermodel.CellStyle;
diff --git a/src/main/java/io/github/hee9841/excel/meta/ColumnInfoMapper.java b/src/main/java/io/github/hee9841/excel/core/meta/ColumnInfoMapper.java
similarity index 99%
rename from src/main/java/io/github/hee9841/excel/meta/ColumnInfoMapper.java
rename to src/main/java/io/github/hee9841/excel/core/meta/ColumnInfoMapper.java
index b56ed60..fd327b6 100644
--- a/src/main/java/io/github/hee9841/excel/meta/ColumnInfoMapper.java
+++ b/src/main/java/io/github/hee9841/excel/core/meta/ColumnInfoMapper.java
@@ -1,4 +1,4 @@
-package io.github.hee9841.excel.meta;
+package io.github.hee9841.excel.core.meta;
 
 import static io.github.hee9841.excel.global.SystemValues.ALLOWED_FIELD_TYPES;
 import static io.github.hee9841.excel.global.SystemValues.ALLOWED_FIELD_TYPES_STRING;
diff --git a/src/main/java/io/github/hee9841/excel/strategy/CellTypeStrategy.java b/src/main/java/io/github/hee9841/excel/strategy/CellTypeStrategy.java
index 6a51f44..7bc79e4 100644
--- a/src/main/java/io/github/hee9841/excel/strategy/CellTypeStrategy.java
+++ b/src/main/java/io/github/hee9841/excel/strategy/CellTypeStrategy.java
@@ -1,13 +1,12 @@
 package io.github.hee9841.excel.strategy;
 
-import io.github.hee9841.excel.meta.ColumnDataType;
 
 /**
  * Strategy enum that determines how cell types are assigned in Excel sheets.
  * <p>
  * This enum defines strategies for determining the data type and format of cells
  * when exporting data to Excel. It works in conjunction with the
- * {@link ColumnDataType} enum to control how different Java types
+ * {@link io.github.hee9841.excel.core.meta.ColumnDataType} enum to control how different Java types
  * are represented in Excel.
  * </p>
  * The available strategies are:
@@ -26,8 +25,8 @@
  *
  * @see io.github.hee9841.excel.annotation.Excel#cellTypeStrategy()
  * @see io.github.hee9841.excel.annotation.ExcelColumn#columnCellType()
- * @see ColumnDataType
- * @see io.github.hee9841.excel.meta.ColumnInfoMapper
+ * @see io.github.hee9841.excel.core.meta.ColumnDataType
+ * @see io.github.hee9841.excel.core.meta.ColumnInfoMapper
  * @see DataFormatStrategy
  */
 public enum CellTypeStrategy {
@@ -36,7 +35,7 @@ public enum CellTypeStrategy {
      * <p>
      * With this strategy, you can explicitly specify the cell type for each column
      * using the {@link io.github.hee9841.excel.annotation.ExcelColumn#columnCellType()} parameter
-     * or if not specified, cell type will be {@link ColumnDataType#_NONE}.
+     * or if not specified, cell type will be {@link io.github.hee9841.excel.core.meta.ColumnDataType#_NONE}.
      * </p>
      */
     NONE,
@@ -50,7 +49,7 @@ public enum CellTypeStrategy {
      * </p>
      * <p>
      * The automatic cell type determination is performed by the
-     * {@link io.github.hee9841.excel.meta.ColumnInfoMapper} class.
+     * {@link io.github.hee9841.excel.core.meta.ColumnInfoMapper} class.
      * If you want to specify the cell type for a specific column, you can use the
      * {@link io.github.hee9841.excel.annotation.ExcelColumn#columnCellType()} parameter.
      * </p>
diff --git a/src/main/java/io/github/hee9841/excel/strategy/ColumnIndexStrategy.java b/src/main/java/io/github/hee9841/excel/strategy/ColumnIndexStrategy.java
index d8ccf14..dcfffa7 100644
--- a/src/main/java/io/github/hee9841/excel/strategy/ColumnIndexStrategy.java
+++ b/src/main/java/io/github/hee9841/excel/strategy/ColumnIndexStrategy.java
@@ -22,7 +22,7 @@
  *
  * @see io.github.hee9841.excel.annotation.Excel#columnIndexStrategy()
  * @see io.github.hee9841.excel.annotation.ExcelColumn#columnIndex()
- * @see io.github.hee9841.excel.meta.ColumnInfoMapper
+ * @see io.github.hee9841.excel.core.meta.ColumnInfoMapper
  */
 public enum ColumnIndexStrategy {
     /**
diff --git a/src/main/java/io/github/hee9841/excel/strategy/DataFormatStrategy.java b/src/main/java/io/github/hee9841/excel/strategy/DataFormatStrategy.java
index a88224d..0eccc0d 100644
--- a/src/main/java/io/github/hee9841/excel/strategy/DataFormatStrategy.java
+++ b/src/main/java/io/github/hee9841/excel/strategy/DataFormatStrategy.java
@@ -1,20 +1,18 @@
 package io.github.hee9841.excel.strategy;
 
-import io.github.hee9841.excel.meta.ColumnDataType;
-
 /**
  * Strategy enum that determines how data formatting is applied to Excel cells.
  * <p>
  * This enum defines strategies for controlling how cell formatting patterns are determined and
  * applied during
- * Excel export operations. It works in conjunction with the {@link ColumnDataType}
+ * Excel export operations. It works in conjunction with the {@link io.github.hee9841.excel.core.meta.ColumnDataType}
  * to apply appropriate formatting to different types of data.
  * <p>
  * The available strategies are:
  * <ul>
  *   <li>{@code NONE}: No automatic formatting is applied. Formatting must be explicitly specified
  *       in the {@link io.github.hee9841.excel.annotation.ExcelColumn} annotation.</li>
- *   <li>{@code AUTO_BY_CELL_TYPE}: Automatic formatting is applied based on the {@link ColumnDataType}, but only when the
+ *   <li>{@code AUTO_BY_CELL_TYPE}: Automatic formatting is applied based on the {@link io.github.hee9841.excel.core.meta.ColumnDataType}, but only when the
  *       {@link io.github.hee9841.excel.annotation.ExcelColumn#columnCellType()} is explicitly set or determined by the {@link CellTypeStrategy} (not when it's NONE).
  *       If user specified the {@code format} parameter in the {@link io.github.hee9841.excel.annotation.ExcelColumn} annotation, it will take precedence over the automatic format.
  *   </li>
@@ -24,7 +22,7 @@
  * annotation and affects all columns unless overridden at the column level.
  *
  * @see io.github.hee9841.excel.annotation.Excel#dataFormatStrategy()
- * @see ColumnDataType
+ * @see io.github.hee9841.excel.core.meta.ColumnDataType
  * @see io.github.hee9841.excel.format.ExcelDataFormater
  * @see io.github.hee9841.excel.format.CellFormats
  */
@@ -45,7 +43,7 @@ public enum DataFormatStrategy {
      * <p>
      * This strategy only applies when the cell type is explicitly set (not NONE) or
      * determined by the {@link CellTypeStrategy} (when set to AUTO). It uses the format
-     * pattern defined for each {@link ColumnDataType} to format
+     * pattern defined for each {@link io.github.hee9841.excel.core.meta.ColumnDataType} to format
      * the cell appropriately for its data type.
      * <p>
      * Note: If a format pattern is explicitly specified in the
diff --git a/src/main/java/io/github/hee9841/excel/strategy/SheetStrategy.java b/src/main/java/io/github/hee9841/excel/strategy/SheetStrategy.java
index 0bfa93a..3c8fa00 100644
--- a/src/main/java/io/github/hee9841/excel/strategy/SheetStrategy.java
+++ b/src/main/java/io/github/hee9841/excel/strategy/SheetStrategy.java
@@ -3,6 +3,7 @@
 import static org.apache.commons.compress.archivers.zip.Zip64Mode.Always;
 import static org.apache.commons.compress.archivers.zip.Zip64Mode.AsNeeded;
 
+
 import java.util.Objects;
 import org.apache.commons.compress.archivers.zip.Zip64Mode;
 
diff --git a/src/test/java/io/github/hee9841/excel/core/ExcelExporterByteOutputStreamTest.java b/src/test/java/io/github/hee9841/excel/core/exporter/DefaultExcelExporterByteOutputStreamTest.java
similarity index 95%
rename from src/test/java/io/github/hee9841/excel/core/ExcelExporterByteOutputStreamTest.java
rename to src/test/java/io/github/hee9841/excel/core/exporter/DefaultExcelExporterByteOutputStreamTest.java
index fb182b6..acc43a9 100644
--- a/src/test/java/io/github/hee9841/excel/core/ExcelExporterByteOutputStreamTest.java
+++ b/src/test/java/io/github/hee9841/excel/core/exporter/DefaultExcelExporterByteOutputStreamTest.java
@@ -1,4 +1,4 @@
-package io.github.hee9841.excel.core;
+package io.github.hee9841.excel.core.exporter;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
@@ -52,8 +52,8 @@
 import org.slf4j.LoggerFactory;
 
 
-@DisplayName("ExcelExporter 테스트")
-class ExcelExporterByteOutputStreamTest {
+@DisplayName("DefaultExcelExporter 테스트")
+class DefaultExcelExporterByteOutputStreamTest {
 
     MemoryAppender memoryAppender;
     String loggerClassName;
@@ -61,8 +61,8 @@ class ExcelExporterByteOutputStreamTest {
 
     @BeforeEach
     void beforeEach() {
-        Logger logger = (Logger) LoggerFactory.getLogger(SXSSFExcelFile.class);
-        loggerClassName = SXSSFExcelFile.class.getName();
+        Logger logger = (Logger) LoggerFactory.getLogger(SXSSFExporter.class);
+        loggerClassName = SXSSFExporter.class.getName();
         memoryAppender = new MemoryAppender();
         memoryAppender.setContext((LoggerContext) LoggerFactory.getILoggerFactory());
         logger.setLevel(Level.DEBUG);
@@ -92,7 +92,7 @@ void dataSizeExceedMaxRowsThrowsException() {
 
         // when & then
         ExcelException exception = assertThrows(ExcelException.class, () ->
-            ExcelExporter.builder(TestDto.class, data)
+            DefaultExcelExporter.builder(TestDto.class, data)
                 .maxRows(maxRows)
                 .sheetStrategy(
                     SheetStrategy.ONE_SHEET) // Force ONE_SHEET strategy to ensure exception is thrown
@@ -113,7 +113,7 @@ void cannotExceedMaxRowOfImplementation() {
         int maxRowOfExcel2007 = 0x100000; // Excel 2007 최대 행 수 초과
 
         // when
-        ExcelException exception = assertThrows(ExcelException.class, () -> ExcelExporter
+        ExcelException exception = assertThrows(ExcelException.class, () -> DefaultExcelExporter
             .builder(TestDto.class, data)
             .maxRows(maxRowOfExcel2007 + 1)
             .build());
@@ -131,7 +131,7 @@ void validateLogSequence() throws IOException {
         data.add(new TestDto("test1", 1));
         data.add(new TestDto("test2", 2));
 
-        ExcelExporter<TestDto> exporter = ExcelExporter
+        DefaultExcelExporter<TestDto> exporter = DefaultExcelExporter
             .builder(TestDto.class, data).build();
 
         exporter.write(os);
@@ -157,7 +157,7 @@ void createEmptyExcelFile() throws IOException {
         // given
         List<TestDto> emptyData = new ArrayList<>();
 
-        ExcelExporter<TestDto> exporter = ExcelExporter
+        DefaultExcelExporter<TestDto> exporter = DefaultExcelExporter
             .builder(TestDto.class, emptyData)
             .build();
 
@@ -193,7 +193,7 @@ void multiSheetMaxRowsExceedTest() throws IOException {
                 testData.add(new TestDto("test" + (i + 1), i + 1));
             }
             // when
-            ExcelExporter.builder(TestDto.class, testData)
+            DefaultExcelExporter.builder(TestDto.class, testData)
                 .maxRows(10)
                 .build().write(os);
 
@@ -237,7 +237,7 @@ void throwExceptionWhenOneSheetAndExceedMaxRows() {
 
             //when
             ExcelException exception = assertThrows(ExcelException.class,
-                () -> ExcelExporter.builder(TestDto.class, testData)
+                () -> DefaultExcelExporter.builder(TestDto.class, testData)
                     .maxRows(10)
                     .sheetStrategy(SheetStrategy.ONE_SHEET)
                     .build()
@@ -265,7 +265,7 @@ void createSheetWithSpecifiedName() throws IOException {
             }
 
             //when
-            ExcelExporter.builder(TestDto.class, testData)
+            DefaultExcelExporter.builder(TestDto.class, testData)
                 .sheetName("TestSheet")
                 .maxRows(10)
                 .build()
@@ -300,7 +300,7 @@ void checkFormulaType() throws IOException {
         }
 
         //when
-        ExcelExporter.builder(TypeAutoDto.class, testData)
+        DefaultExcelExporter.builder(TypeAutoDto.class, testData)
             .sheetName("TestSheet")
             .build()
             .write(os);
@@ -346,7 +346,7 @@ class TestDto {
         testData.add(new TestDto());
 
         //when
-        ExcelExporter.builder(TestDto.class, testData)
+        DefaultExcelExporter.builder(TestDto.class, testData)
             .build()
             .write(os);
 
@@ -402,7 +402,7 @@ void createExcelFileWithSpecifiedCellStyle() throws IOException {
             testData.add(new TestDto("name value", 1));
 
             //when
-            ExcelExporter.builder(TestDto.class, testData)
+            DefaultExcelExporter.builder(TestDto.class, testData)
                 .build()
                 .write(os);
 
@@ -454,7 +454,7 @@ void createExcelFileWithSpecifiedDataFormat() throws IOException {
         String signUpDatePattern = CellFormats.DEFAULT_DATE_FORMAT;
 
         //when
-        ExcelExporter.builder(TestDto.class, testData)
+        DefaultExcelExporter.builder(TestDto.class, testData)
             .build()
             .write(os);
 
diff --git a/src/test/java/io/github/hee9841/excel/meta/CellStyleMappingTest.java b/src/test/java/io/github/hee9841/excel/core/meta/CellStyleMappingTest.java
similarity index 99%
rename from src/test/java/io/github/hee9841/excel/meta/CellStyleMappingTest.java
rename to src/test/java/io/github/hee9841/excel/core/meta/CellStyleMappingTest.java
index 5deeeb5..7d9045b 100644
--- a/src/test/java/io/github/hee9841/excel/meta/CellStyleMappingTest.java
+++ b/src/test/java/io/github/hee9841/excel/core/meta/CellStyleMappingTest.java
@@ -1,4 +1,4 @@
-package io.github.hee9841.excel.meta;
+package io.github.hee9841.excel.core.meta;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertInstanceOf;
diff --git a/src/test/java/io/github/hee9841/excel/meta/ColumnDataTypeTest.java b/src/test/java/io/github/hee9841/excel/core/meta/ColumnDataTypeTest.java
similarity index 99%
rename from src/test/java/io/github/hee9841/excel/meta/ColumnDataTypeTest.java
rename to src/test/java/io/github/hee9841/excel/core/meta/ColumnDataTypeTest.java
index 2b45d0e..824a34b 100644
--- a/src/test/java/io/github/hee9841/excel/meta/ColumnDataTypeTest.java
+++ b/src/test/java/io/github/hee9841/excel/core/meta/ColumnDataTypeTest.java
@@ -1,4 +1,4 @@
-package io.github.hee9841.excel.meta;
+package io.github.hee9841.excel.core.meta;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.mockito.BDDMockito.then;
diff --git a/src/test/java/io/github/hee9841/excel/meta/ColumnInfoMapperTest.java b/src/test/java/io/github/hee9841/excel/core/meta/ColumnInfoMapperTest.java
similarity index 99%
rename from src/test/java/io/github/hee9841/excel/meta/ColumnInfoMapperTest.java
rename to src/test/java/io/github/hee9841/excel/core/meta/ColumnInfoMapperTest.java
index 4e50cea..d39d136 100644
--- a/src/test/java/io/github/hee9841/excel/meta/ColumnInfoMapperTest.java
+++ b/src/test/java/io/github/hee9841/excel/core/meta/ColumnInfoMapperTest.java
@@ -1,4 +1,4 @@
-package io.github.hee9841.excel.meta;
+package io.github.hee9841.excel.core.meta;
 
 import static io.github.hee9841.excel.strategy.ColumnIndexStrategy.USER_DEFINED;
 import static org.junit.jupiter.api.Assertions.assertEquals;
diff --git a/src/test/java/io/github/hee9841/excel/example/dto/TypeAutoDto.java b/src/test/java/io/github/hee9841/excel/example/dto/TypeAutoDto.java
index f8bb114..dde43d5 100644
--- a/src/test/java/io/github/hee9841/excel/example/dto/TypeAutoDto.java
+++ b/src/test/java/io/github/hee9841/excel/example/dto/TypeAutoDto.java
@@ -2,7 +2,7 @@
 
 import io.github.hee9841.excel.annotation.Excel;
 import io.github.hee9841.excel.annotation.ExcelColumn;
-import io.github.hee9841.excel.meta.ColumnDataType;
+import io.github.hee9841.excel.core.meta.ColumnDataType;
 import io.github.hee9841.excel.strategy.CellTypeStrategy;
 import io.github.hee9841.excel.strategy.ColumnIndexStrategy;
 import java.time.LocalDate;