diff --git a/pom.xml b/pom.xml
index c818dd3..e85d044 100644
--- a/pom.xml
+++ b/pom.xml
@@ -4,7 +4,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.alibaba</groupId>
     <artifactId>easyexcel</artifactId>
-    <version>2.1.2</version>
+    <version>2.1.3</version>
     <packaging>jar</packaging>
     <name>easyexcel</name>
 
diff --git a/src/main/java/com/alibaba/excel/analysis/ExcelAnalyserImpl.java b/src/main/java/com/alibaba/excel/analysis/ExcelAnalyserImpl.java
index f3ef950..eb4f188 100644
--- a/src/main/java/com/alibaba/excel/analysis/ExcelAnalyserImpl.java
+++ b/src/main/java/com/alibaba/excel/analysis/ExcelAnalyserImpl.java
@@ -176,7 +176,7 @@ public class ExcelAnalyserImpl implements ExcelAnalyser {
         clearEncrypt03();
 
         if (throwable != null) {
-            throw new ExcelAnalysisException("Can not close IO", throwable);
+            throw new ExcelAnalysisException("Can not close IO.", throwable);
         }
     }
 
diff --git a/src/main/java/com/alibaba/excel/analysis/v07/XlsxSaxAnalyser.java b/src/main/java/com/alibaba/excel/analysis/v07/XlsxSaxAnalyser.java
index a30b426..2862be2 100644
--- a/src/main/java/com/alibaba/excel/analysis/v07/XlsxSaxAnalyser.java
+++ b/src/main/java/com/alibaba/excel/analysis/v07/XlsxSaxAnalyser.java
@@ -34,6 +34,7 @@ import com.alibaba.excel.read.metadata.holder.ReadWorkbookHolder;
 import com.alibaba.excel.util.CollectionUtils;
 import com.alibaba.excel.util.FileUtils;
 import com.alibaba.excel.util.SheetUtils;
+import com.alibaba.excel.util.StringUtils;
 
 /**
  *
@@ -148,7 +149,13 @@ public class XlsxSaxAnalyser implements ExcelReadExecutor {
     private void parseXmlSource(InputStream inputStream, ContentHandler handler) {
         InputSource inputSource = new InputSource(inputStream);
         try {
-            SAXParserFactory saxFactory = SAXParserFactory.newInstance();
+            SAXParserFactory saxFactory;
+            String xlsxSAXParserFactoryName = analysisContext.readWorkbookHolder().getXlsxSAXParserFactoryName();
+            if (StringUtils.isEmpty(xlsxSAXParserFactoryName)) {
+                saxFactory = SAXParserFactory.newInstance();
+            } else {
+                saxFactory = SAXParserFactory.newInstance(xlsxSAXParserFactoryName, null);
+            }
             saxFactory.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
             saxFactory.setFeature("http://xml.org/sax/features/external-general-entities", false);
             saxFactory.setFeature("http://xml.org/sax/features/external-parameter-entities", false);
diff --git a/src/main/java/com/alibaba/excel/context/WriteContextImpl.java b/src/main/java/com/alibaba/excel/context/WriteContextImpl.java
index 8420502..a07ad4c 100644
--- a/src/main/java/com/alibaba/excel/context/WriteContextImpl.java
+++ b/src/main/java/com/alibaba/excel/context/WriteContextImpl.java
@@ -169,7 +169,9 @@ public class WriteContextImpl implements WriteContext {
         int newRowIndex = writeSheetHolder.getNewRowIndexAndStartDoWrite();
         newRowIndex += currentWriteHolder.relativeHeadRowIndex();
         // Combined head
-        addMergedRegionToCurrentSheet(excelWriteHeadProperty, newRowIndex);
+        if (currentWriteHolder.automaticMergeHead()) {
+            addMergedRegionToCurrentSheet(excelWriteHeadProperty, newRowIndex);
+        }
         for (int relativeRowIndex = 0, i = newRowIndex; i < excelWriteHeadProperty.getHeadRowNumber() + newRowIndex;
             i++, relativeRowIndex++) {
             WriteHandlerUtils.beforeRowCreate(this, newRowIndex, relativeRowIndex, Boolean.TRUE);
@@ -182,8 +184,9 @@ public class WriteContextImpl implements WriteContext {
 
     private void addMergedRegionToCurrentSheet(ExcelWriteHeadProperty excelWriteHeadProperty, int rowIndex) {
         for (com.alibaba.excel.metadata.CellRange cellRangeModel : excelWriteHeadProperty.headCellRangeList()) {
-            writeSheetHolder.getSheet().addMergedRegion(new CellRangeAddress(cellRangeModel.getFirstRow() + rowIndex,
-                cellRangeModel.getLastRow() + rowIndex, cellRangeModel.getFirstCol(), cellRangeModel.getLastCol()));
+            writeSheetHolder.getSheet()
+                .addMergedRegionUnsafe(new CellRangeAddress(cellRangeModel.getFirstRow() + rowIndex,
+                    cellRangeModel.getLastRow() + rowIndex, cellRangeModel.getFirstCol(), cellRangeModel.getLastCol()));
         }
     }
 
@@ -325,7 +328,7 @@ public class WriteContextImpl implements WriteContext {
         clearEncrypt03();
 
         if (throwable != null) {
-            throw new ExcelGenerateException("Can not close IO", throwable);
+            throw new ExcelGenerateException("Can not close IO.", throwable);
         }
 
         if (LOGGER.isDebugEnabled()) {
diff --git a/src/main/java/com/alibaba/excel/read/builder/ExcelReaderBuilder.java b/src/main/java/com/alibaba/excel/read/builder/ExcelReaderBuilder.java
index 340548b..4f6cdda 100644
--- a/src/main/java/com/alibaba/excel/read/builder/ExcelReaderBuilder.java
+++ b/src/main/java/com/alibaba/excel/read/builder/ExcelReaderBuilder.java
@@ -5,6 +5,8 @@ import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.List;
 
+import javax.xml.parsers.SAXParserFactory;
+
 import com.alibaba.excel.ExcelReader;
 import com.alibaba.excel.cache.ReadCache;
 import com.alibaba.excel.cache.selector.ReadCacheSelector;
@@ -233,6 +235,23 @@ public class ExcelReaderBuilder {
         return this;
     }
 
+    /**
+     * SAXParserFactory used when reading xlsx.
+     * <p>
+     * The default will automatically find.
+     * <p>
+     * Please pass in the name of a class ,like : "com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl"
+     *
+     * @see SAXParserFactory#newInstance()
+     * @see SAXParserFactory#newInstance(String, ClassLoader)
+     * @param xlsxSAXParserFactoryName
+     * @return
+     */
+    public ExcelReaderBuilder xlsxSAXParserFactoryName(String xlsxSAXParserFactoryName) {
+        readWorkbook.setXlsxSAXParserFactoryName(xlsxSAXParserFactoryName);
+        return this;
+    }
+
     public ExcelReader build() {
         return new ExcelReader(readWorkbook);
     }
diff --git a/src/main/java/com/alibaba/excel/read/metadata/ReadWorkbook.java b/src/main/java/com/alibaba/excel/read/metadata/ReadWorkbook.java
index 3a873da..c6bbf7a 100644
--- a/src/main/java/com/alibaba/excel/read/metadata/ReadWorkbook.java
+++ b/src/main/java/com/alibaba/excel/read/metadata/ReadWorkbook.java
@@ -3,6 +3,8 @@ package com.alibaba.excel.read.metadata;
 import java.io.File;
 import java.io.InputStream;
 
+import javax.xml.parsers.SAXParserFactory;
+
 import com.alibaba.excel.cache.ReadCache;
 import com.alibaba.excel.cache.selector.ReadCacheSelector;
 import com.alibaba.excel.context.AnalysisContext;
@@ -63,6 +65,17 @@ public class ReadWorkbook extends ReadBasicParameter {
      * Whether the encryption
      */
     private String password;
+    /**
+     * SAXParserFactory used when reading xlsx.
+     * <p>
+     * The default will automatically find.
+     * <p>
+     * Please pass in the name of a class ,like : "com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl"
+     *
+     * @see SAXParserFactory#newInstance()
+     * @see SAXParserFactory#newInstance(String, ClassLoader)
+     */
+    private String xlsxSAXParserFactoryName;
     /**
      * The default is all excel objects.Default is true.
      * <p>
@@ -176,4 +189,12 @@ public class ReadWorkbook extends ReadBasicParameter {
     public void setPassword(String password) {
         this.password = password;
     }
+
+    public String getXlsxSAXParserFactoryName() {
+        return xlsxSAXParserFactoryName;
+    }
+
+    public void setXlsxSAXParserFactoryName(String xlsxSAXParserFactoryName) {
+        this.xlsxSAXParserFactoryName = xlsxSAXParserFactoryName;
+    }
 }
diff --git a/src/main/java/com/alibaba/excel/read/metadata/holder/ReadWorkbookHolder.java b/src/main/java/com/alibaba/excel/read/metadata/holder/ReadWorkbookHolder.java
index 35b3859..cbda93f 100644
--- a/src/main/java/com/alibaba/excel/read/metadata/holder/ReadWorkbookHolder.java
+++ b/src/main/java/com/alibaba/excel/read/metadata/holder/ReadWorkbookHolder.java
@@ -6,6 +6,8 @@ import java.io.InputStream;
 import java.util.HashSet;
 import java.util.Set;
 
+import javax.xml.parsers.SAXParserFactory;
+
 import org.apache.poi.openxml4j.opc.OPCPackage;
 import org.apache.poi.poifs.filesystem.POIFSFileSystem;
 
@@ -83,6 +85,17 @@ public class ReadWorkbookHolder extends AbstractReadHolder {
      * Whether the encryption
      */
     private String password;
+    /**
+     * SAXParserFactory used when reading xlsx.
+     * <p>
+     * The default will automatically find.
+     * <p>
+     * Please pass in the name of a class ,like : "com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl"
+     *
+     * @see SAXParserFactory#newInstance()
+     * @see SAXParserFactory#newInstance(String, ClassLoader)
+     */
+    private String xlsxSAXParserFactoryName;
     /**
      * The default is all excel objects.if true , you can use {@link com.alibaba.excel.annotation.ExcelIgnore} ignore a
      * field. if false , you must use {@link com.alibaba.excel.annotation.ExcelProperty} to use a filed.
@@ -172,6 +185,7 @@ public class ReadWorkbookHolder extends AbstractReadHolder {
         } else {
             this.defaultReturnMap = readWorkbook.getDefaultReturnMap();
         }
+        this.xlsxSAXParserFactoryName = readWorkbook.getXlsxSAXParserFactoryName();
         this.hasReadSheet = new HashSet<Integer>();
         this.ignoreRecord03 = Boolean.FALSE;
         this.password = readWorkbook.getPassword();
@@ -321,6 +335,14 @@ public class ReadWorkbookHolder extends AbstractReadHolder {
         this.password = password;
     }
 
+    public String getXlsxSAXParserFactoryName() {
+        return xlsxSAXParserFactoryName;
+    }
+
+    public void setXlsxSAXParserFactoryName(String xlsxSAXParserFactoryName) {
+        this.xlsxSAXParserFactoryName = xlsxSAXParserFactoryName;
+    }
+
     @Override
     public HolderEnum holderType() {
         return HolderEnum.WORKBOOK;
diff --git a/src/main/java/com/alibaba/excel/util/FileUtils.java b/src/main/java/com/alibaba/excel/util/FileUtils.java
index 34e6853..20b16bc 100644
--- a/src/main/java/com/alibaba/excel/util/FileUtils.java
+++ b/src/main/java/com/alibaba/excel/util/FileUtils.java
@@ -9,24 +9,50 @@ import java.io.InputStream;
 import java.io.OutputStream;
 import java.util.UUID;
 
+import org.apache.poi.util.DefaultTempFileCreationStrategy;
+import org.apache.poi.util.TempFile;
+
 import com.alibaba.excel.exception.ExcelAnalysisException;
-import com.alibaba.excel.exception.ExcelGenerateException;
+import com.alibaba.excel.exception.ExcelCommonException;
 
 /**
  *
  * @author jipengfei
  */
 public class FileUtils {
+    public static final String POI_FILES = "poifiles";
+    public static final String EX_CACHE = "excache";
+    /**
+     * If a server has multiple projects in use at the same time, a directory with the same name will be created under
+     * the temporary directory, but each project is run by a different user, so there is a permission problem, so each
+     * project creates a unique UUID as a separate Temporary Files.
+     */
+    private static String tempFilePrefix =
+        System.getProperty(TempFile.JAVA_IO_TMPDIR) + File.separator + UUID.randomUUID().toString() + File.separator;
+    /**
+     * Used to store poi temporary files.
+     */
+    private static String poiFilesPath = tempFilePrefix + POI_FILES + File.separator;
+    /**
+     * Used to store easy excel temporary files.
+     */
+    private static String cachePath = tempFilePrefix + EX_CACHE + File.separator;
 
-    private static final String JAVA_IO_TMPDIR = "java.io.tmpdir";
-
-    private static final String POIFILES = "poifiles";
-
-    private static final String CACHE = "excache";
     private static final int WRITE_BUFF_SIZE = 8192;
 
     private FileUtils() {}
 
+    static {
+        // Create a temporary directory in advance
+        File tempFile = new File(tempFilePrefix);
+        createDirectory(tempFile);
+        tempFile.deleteOnExit();
+        // Initialize the cache directory
+        File cacheFile = new File(cachePath);
+        createDirectory(cacheFile);
+        cacheFile.deleteOnExit();
+    }
+
     /**
      * Reads the contents of a file into a byte array. * The file is always closed.
      *
@@ -106,19 +132,31 @@ public class FileUtils {
         }
     }
 
-    /**
-     */
     public static void createPoiFilesDirectory() {
-        createTmpDirectory(POIFILES);
+        File poiFilesPathFile = new File(poiFilesPath);
+        createDirectory(poiFilesPathFile);
+        TempFile.setTempFileCreationStrategy(new DefaultTempFileCreationStrategy(poiFilesPathFile));
+        poiFilesPathFile.deleteOnExit();
     }
 
     public static File createCacheTmpFile() {
-        File directory = createTmpDirectory(CACHE);
-        File cache = new File(directory.getPath(), UUID.randomUUID().toString());
-        if (!cache.mkdir()) {
-            throw new ExcelGenerateException("Can not create temp file!");
+        return createDirectory(new File(cachePath + UUID.randomUUID().toString()));
+    }
+
+    public static File createTmpFile(String fileName) {
+        File directory = createDirectory(new File(tempFilePrefix));
+        return new File(directory, fileName);
+    }
+
+    /**
+     *
+     * @param directory
+     */
+    private static File createDirectory(File directory) {
+        if (!directory.exists() && !directory.mkdirs()) {
+            throw new ExcelCommonException("Cannot create directory:" + directory.getAbsolutePath());
         }
-        return cache;
+        return directory;
     }
 
     /**
@@ -144,35 +182,27 @@ public class FileUtils {
         }
     }
 
-    public static File createTmpDirectory(String path) {
-        String tmpDir = System.getProperty(JAVA_IO_TMPDIR);
-        if (tmpDir == null) {
-            throw new RuntimeException(
-                "Systems temporary directory not defined - set the -D" + JAVA_IO_TMPDIR + " jvm property!");
-        }
-        File directory = new File(tmpDir, path);
-        if (!directory.exists()) {
-            syncCreatePoiFilesDirectory(directory);
-        }
-        return directory;
+    public static String getTempFilePrefix() {
+        return tempFilePrefix;
     }
 
-    public static File createTmpFile(String fileName) {
-        String tmpDir = System.getProperty(JAVA_IO_TMPDIR);
-        if (tmpDir == null) {
-            throw new RuntimeException(
-                "Systems temporary directory not defined - set the -D" + JAVA_IO_TMPDIR + " jvm property!");
-        }
-        return new File(tmpDir, fileName);
+    public static void setTempFilePrefix(String tempFilePrefix) {
+        FileUtils.tempFilePrefix = tempFilePrefix;
     }
 
-    /**
-     *
-     * @param directory
-     */
-    private static synchronized void syncCreatePoiFilesDirectory(File directory) {
-        if (!directory.exists()) {
-            directory.mkdirs();
-        }
+    public static String getPoiFilesPath() {
+        return poiFilesPath;
+    }
+
+    public static void setPoiFilesPath(String poiFilesPath) {
+        FileUtils.poiFilesPath = poiFilesPath;
+    }
+
+    public static String getCachePath() {
+        return cachePath;
+    }
+
+    public static void setCachePath(String cachePath) {
+        FileUtils.cachePath = cachePath;
     }
 }
diff --git a/src/main/java/com/alibaba/excel/write/builder/ExcelWriterBuilder.java b/src/main/java/com/alibaba/excel/write/builder/ExcelWriterBuilder.java
index f0d37ed..c1f2d94 100644
--- a/src/main/java/com/alibaba/excel/write/builder/ExcelWriterBuilder.java
+++ b/src/main/java/com/alibaba/excel/write/builder/ExcelWriterBuilder.java
@@ -91,6 +91,17 @@ public class ExcelWriterBuilder {
         return this;
     }
 
+    /**
+     * Whether to automatically merge headers.Default is true.
+     *
+     * @param automaticMergeHead
+     * @return
+     */
+    public ExcelWriterBuilder automaticMergeHead(Boolean automaticMergeHead) {
+        writeWorkbook.setAutomaticMergeHead(automaticMergeHead);
+        return this;
+    }
+
     /**
      * Whether the encryption.
      * <p>
diff --git a/src/main/java/com/alibaba/excel/write/builder/ExcelWriterSheetBuilder.java b/src/main/java/com/alibaba/excel/write/builder/ExcelWriterSheetBuilder.java
index 50f230a..5cb71cc 100644
--- a/src/main/java/com/alibaba/excel/write/builder/ExcelWriterSheetBuilder.java
+++ b/src/main/java/com/alibaba/excel/write/builder/ExcelWriterSheetBuilder.java
@@ -86,6 +86,17 @@ public class ExcelWriterSheetBuilder {
         return this;
     }
 
+    /**
+     * Whether to automatically merge headers.Default is true.
+     *
+     * @param automaticMergeHead
+     * @return
+     */
+    public ExcelWriterSheetBuilder automaticMergeHead(Boolean automaticMergeHead) {
+        writeSheet.setAutomaticMergeHead(automaticMergeHead);
+        return this;
+    }
+
     /**
      * Custom type conversions override the default.
      *
diff --git a/src/main/java/com/alibaba/excel/write/builder/ExcelWriterTableBuilder.java b/src/main/java/com/alibaba/excel/write/builder/ExcelWriterTableBuilder.java
index 40ca58b..2b461a9 100644
--- a/src/main/java/com/alibaba/excel/write/builder/ExcelWriterTableBuilder.java
+++ b/src/main/java/com/alibaba/excel/write/builder/ExcelWriterTableBuilder.java
@@ -90,6 +90,17 @@ public class ExcelWriterTableBuilder {
         return this;
     }
 
+    /**
+     * Whether to automatically merge headers.Default is true.
+     *
+     * @param automaticMergeHead
+     * @return
+     */
+    public ExcelWriterTableBuilder automaticMergeHead(Boolean automaticMergeHead) {
+        writeTable.setAutomaticMergeHead(automaticMergeHead);
+        return this;
+    }
+
     /**
      * Custom type conversions override the default.
      *
@@ -129,7 +140,6 @@ public class ExcelWriterTableBuilder {
         return this;
     }
 
-
     /**
      * Ignore the custom columns.
      */
diff --git a/src/main/java/com/alibaba/excel/write/executor/ExcelWriteFillExecutor.java b/src/main/java/com/alibaba/excel/write/executor/ExcelWriteFillExecutor.java
index 473d4e3..495a134 100644
--- a/src/main/java/com/alibaba/excel/write/executor/ExcelWriteFillExecutor.java
+++ b/src/main/java/com/alibaba/excel/write/executor/ExcelWriteFillExecutor.java
@@ -21,7 +21,6 @@ import com.alibaba.excel.enums.WriteDirectionEnum;
 import com.alibaba.excel.enums.WriteTemplateAnalysisCellTypeEnum;
 import com.alibaba.excel.exception.ExcelGenerateException;
 import com.alibaba.excel.metadata.CellData;
-import com.alibaba.excel.metadata.Head;
 import com.alibaba.excel.metadata.property.ExcelContentProperty;
 import com.alibaba.excel.util.CollectionUtils;
 import com.alibaba.excel.util.StringUtils;
@@ -69,6 +68,8 @@ public class ExcelWriteFillExecutor extends AbstractExcelWriteExecutor {
     private Map<Integer, Map<AnalysisCell, Integer>> collectionLastIndexCache =
         new HashMap<Integer, Map<AnalysisCell, Integer>>(8);
 
+    private Map<Integer, Integer> relativeRowIndexMap = new HashMap<Integer, Integer>(8);
+
     public ExcelWriteFillExecutor(WriteContext writeContext) {
         super(writeContext);
     }
@@ -89,10 +90,10 @@ public class ExcelWriteFillExecutor extends AbstractExcelWriteExecutor {
                 shiftRows(collectionData.size(), analysisCellList);
             }
             while (iterator.hasNext()) {
-                doFill(analysisCellList, iterator.next(), fillConfig);
+                doFill(analysisCellList, iterator.next(), fillConfig, getRelativeRowIndex());
             }
         } else {
-            doFill(readTemplateData(templateAnalysisCache), data, fillConfig);
+            doFill(readTemplateData(templateAnalysisCache), data, fillConfig, null);
         }
     }
 
@@ -138,7 +139,8 @@ public class ExcelWriteFillExecutor extends AbstractExcelWriteExecutor {
         }
     }
 
-    private void doFill(List<AnalysisCell> analysisCellList, Object oneRowData, FillConfig fillConfig) {
+    private void doFill(List<AnalysisCell> analysisCellList, Object oneRowData, FillConfig fillConfig,
+        Integer relativeRowIndex) {
         Map dataMap;
         if (oneRowData instanceof Map) {
             dataMap = (Map)oneRowData;
@@ -161,7 +163,7 @@ public class ExcelWriteFillExecutor extends AbstractExcelWriteExecutor {
                 Object value = dataMap.get(variable);
                 CellData cellData = converterAndSet(writeSheetHolder, value == null ? null : value.getClass(), cell,
                     value, fieldNameContentPropertyMap.get(variable));
-                WriteHandlerUtils.afterCellDispose(writeContext, cellData, cell, null, null, Boolean.FALSE);
+                WriteHandlerUtils.afterCellDispose(writeContext, cellData, cell, null, relativeRowIndex, Boolean.FALSE);
             } else {
                 StringBuilder cellValueBuild = new StringBuilder();
                 int index = 0;
@@ -197,11 +199,24 @@ public class ExcelWriteFillExecutor extends AbstractExcelWriteExecutor {
                 }
                 cellValueBuild.append(analysisCell.getPrepareDataList().get(index));
                 cell.setCellValue(cellValueBuild.toString());
-                WriteHandlerUtils.afterCellDispose(writeContext, cellDataList, cell, null, null, Boolean.FALSE);
+                WriteHandlerUtils.afterCellDispose(writeContext, cellDataList, cell, null, relativeRowIndex,
+                    Boolean.FALSE);
             }
         }
     }
 
+    private Integer getRelativeRowIndex() {
+        Integer sheetNo = writeContext.writeSheetHolder().getSheetNo();
+        Integer relativeRowIndex = relativeRowIndexMap.get(sheetNo);
+        if (relativeRowIndex == null) {
+            relativeRowIndex = 0;
+        } else {
+            relativeRowIndex++;
+        }
+        relativeRowIndexMap.put(sheetNo, relativeRowIndex);
+        return relativeRowIndex;
+    }
+
     private Cell getOneCell(AnalysisCell analysisCell, FillConfig fillConfig) {
         Sheet cachedSheet = writeContext.writeSheetHolder().getCachedSheet();
         if (WriteTemplateAnalysisCellTypeEnum.COMMON.equals(analysisCell.getCellType())) {
diff --git a/src/main/java/com/alibaba/excel/write/merge/AbstractMergeStrategy.java b/src/main/java/com/alibaba/excel/write/merge/AbstractMergeStrategy.java
index 13bdac3..b661c12 100644
--- a/src/main/java/com/alibaba/excel/write/merge/AbstractMergeStrategy.java
+++ b/src/main/java/com/alibaba/excel/write/merge/AbstractMergeStrategy.java
@@ -45,5 +45,5 @@ public abstract class AbstractMergeStrategy implements CellWriteHandler {
      * @param head
      * @param relativeRowIndex
      */
-    protected abstract void merge(Sheet sheet, Cell cell, Head head, int relativeRowIndex);
+    protected abstract void merge(Sheet sheet, Cell cell, Head head, Integer relativeRowIndex);
 }
diff --git a/src/main/java/com/alibaba/excel/write/merge/LoopMergeStrategy.java b/src/main/java/com/alibaba/excel/write/merge/LoopMergeStrategy.java
index b087804..615e408 100644
--- a/src/main/java/com/alibaba/excel/write/merge/LoopMergeStrategy.java
+++ b/src/main/java/com/alibaba/excel/write/merge/LoopMergeStrategy.java
@@ -39,14 +39,20 @@ public class LoopMergeStrategy extends AbstractMergeStrategy {
     }
 
     @Override
-    protected void merge(Sheet sheet, Cell cell, Head head, int relativeRowIndex) {
-        if (head.getColumnIndex() == columnIndex && relativeRowIndex % eachRow == 0) {
-            CellRangeAddress cellRangeAddress = new CellRangeAddress(
-                cell.getRowIndex(),
-                cell.getRowIndex() + eachRow - 1,
-                cell.getColumnIndex(),
-                cell.getColumnIndex() + columnCount - 1);
-            sheet.addMergedRegion(cellRangeAddress);
+    protected void merge(Sheet sheet, Cell cell, Head head, Integer relativeRowIndex) {
+        if (relativeRowIndex == null) {
+            return;
+        }
+        Integer currentColumnIndex;
+        if (head != null) {
+            currentColumnIndex = head.getColumnIndex();
+        } else {
+            currentColumnIndex = cell.getColumnIndex();
+        }
+        if (currentColumnIndex == columnIndex && relativeRowIndex % eachRow == 0) {
+            CellRangeAddress cellRangeAddress = new CellRangeAddress(cell.getRowIndex(),
+                cell.getRowIndex() + eachRow - 1, cell.getColumnIndex(), cell.getColumnIndex() + columnCount - 1);
+            sheet.addMergedRegionUnsafe(cellRangeAddress);
         }
     }
 }
diff --git a/src/main/java/com/alibaba/excel/write/merge/OnceAbsoluteMergeStrategy.java b/src/main/java/com/alibaba/excel/write/merge/OnceAbsoluteMergeStrategy.java
index 6717b76..be05e22 100644
--- a/src/main/java/com/alibaba/excel/write/merge/OnceAbsoluteMergeStrategy.java
+++ b/src/main/java/com/alibaba/excel/write/merge/OnceAbsoluteMergeStrategy.java
@@ -29,11 +29,11 @@ public class OnceAbsoluteMergeStrategy extends AbstractMergeStrategy {
     }
 
     @Override
-    protected void merge(Sheet sheet, Cell cell, Head head, int relativeRowIndex) {
+    protected void merge(Sheet sheet, Cell cell, Head head, Integer relativeRowIndex) {
         if (cell.getRowIndex() == firstRowIndex && cell.getColumnIndex() == firstColumnIndex) {
             CellRangeAddress cellRangeAddress =
                 new CellRangeAddress(firstRowIndex, lastRowIndex, firstColumnIndex, lastColumnIndex);
-            sheet.addMergedRegion(cellRangeAddress);
+            sheet.addMergedRegionUnsafe(cellRangeAddress);
         }
     }
 }
diff --git a/src/main/java/com/alibaba/excel/write/metadata/WriteBasicParameter.java b/src/main/java/com/alibaba/excel/write/metadata/WriteBasicParameter.java
index 61115af..b582576 100644
--- a/src/main/java/com/alibaba/excel/write/metadata/WriteBasicParameter.java
+++ b/src/main/java/com/alibaba/excel/write/metadata/WriteBasicParameter.java
@@ -29,6 +29,10 @@ public class WriteBasicParameter extends BasicParameter {
      * Use the default style.Default is true.
      */
     private Boolean useDefaultStyle;
+    /**
+     * Whether to automatically merge headers.Default is true.
+     */
+    private Boolean automaticMergeHead;
     /**
      * Ignore the custom columns.
      */
@@ -78,6 +82,14 @@ public class WriteBasicParameter extends BasicParameter {
         this.useDefaultStyle = useDefaultStyle;
     }
 
+    public Boolean getAutomaticMergeHead() {
+        return automaticMergeHead;
+    }
+
+    public void setAutomaticMergeHead(Boolean automaticMergeHead) {
+        this.automaticMergeHead = automaticMergeHead;
+    }
+
     public Collection<Integer> getExcludeColumnIndexes() {
         return excludeColumnIndexes;
     }
@@ -109,4 +121,5 @@ public class WriteBasicParameter extends BasicParameter {
     public void setIncludeColumnFiledNames(Collection<String> includeColumnFiledNames) {
         this.includeColumnFiledNames = includeColumnFiledNames;
     }
+
 }
diff --git a/src/main/java/com/alibaba/excel/write/metadata/holder/AbstractWriteHolder.java b/src/main/java/com/alibaba/excel/write/metadata/holder/AbstractWriteHolder.java
index b28f267..375602a 100644
--- a/src/main/java/com/alibaba/excel/write/metadata/holder/AbstractWriteHolder.java
+++ b/src/main/java/com/alibaba/excel/write/metadata/holder/AbstractWriteHolder.java
@@ -66,6 +66,10 @@ public abstract class AbstractWriteHolder extends AbstractHolder implements Writ
      * Use the default style.Default is true.
      */
     private Boolean useDefaultStyle;
+    /**
+     * Whether to automatically merge headers.Default is true.
+     */
+    private Boolean automaticMergeHead;
     /**
      * Ignore the custom columns.
      */
@@ -127,6 +131,16 @@ public abstract class AbstractWriteHolder extends AbstractHolder implements Writ
             this.useDefaultStyle = writeBasicParameter.getUseDefaultStyle();
         }
 
+        if (writeBasicParameter.getAutomaticMergeHead() == null) {
+            if (parentAbstractWriteHolder == null) {
+                this.automaticMergeHead = Boolean.TRUE;
+            } else {
+                this.automaticMergeHead = parentAbstractWriteHolder.getAutomaticMergeHead();
+            }
+        } else {
+            this.automaticMergeHead = writeBasicParameter.getAutomaticMergeHead();
+        }
+
         if (writeBasicParameter.getExcludeColumnFiledNames() == null && parentAbstractWriteHolder != null) {
             this.excludeColumnFiledNames = parentAbstractWriteHolder.getExcludeColumnFiledNames();
         } else {
@@ -251,7 +265,7 @@ public abstract class AbstractWriteHolder extends AbstractHolder implements Writ
         }
         writeBasicParameter.getCustomWriteHandlerList().add(new AbstractHeadColumnWidthStyleStrategy() {
             @Override
-            protected Integer columnWidth(Head head) {
+            protected Integer columnWidth(Head head, Integer columnIndex) {
                 if (columnWidthMap.containsKey(head.getColumnIndex())) {
                     return columnWidthMap.get(head.getColumnIndex()) / 256;
                 }
@@ -300,7 +314,7 @@ public abstract class AbstractWriteHolder extends AbstractHolder implements Writ
     private void dealColumnWidth(List<WriteHandler> handlerList) {
         WriteHandler columnWidthStyleStrategy = new AbstractHeadColumnWidthStyleStrategy() {
             @Override
-            protected Integer columnWidth(Head head) {
+            protected Integer columnWidth(Head head, Integer columnIndex) {
                 if (head == null) {
                     return null;
                 }
@@ -441,6 +455,14 @@ public abstract class AbstractWriteHolder extends AbstractHolder implements Writ
         this.useDefaultStyle = useDefaultStyle;
     }
 
+    public Boolean getAutomaticMergeHead() {
+        return automaticMergeHead;
+    }
+
+    public void setAutomaticMergeHead(Boolean automaticMergeHead) {
+        this.automaticMergeHead = automaticMergeHead;
+    }
+
     public Collection<Integer> getExcludeColumnIndexes() {
         return excludeColumnIndexes;
     }
@@ -492,4 +514,9 @@ public abstract class AbstractWriteHolder extends AbstractHolder implements Writ
     public int relativeHeadRowIndex() {
         return getRelativeHeadRowIndex();
     }
+
+    @Override
+    public boolean automaticMergeHead() {
+        return getAutomaticMergeHead();
+    }
 }
diff --git a/src/main/java/com/alibaba/excel/write/metadata/holder/WriteHolder.java b/src/main/java/com/alibaba/excel/write/metadata/holder/WriteHolder.java
index 8f2ae7e..2aa2066 100644
--- a/src/main/java/com/alibaba/excel/write/metadata/holder/WriteHolder.java
+++ b/src/main/java/com/alibaba/excel/write/metadata/holder/WriteHolder.java
@@ -44,6 +44,13 @@ public interface WriteHolder extends ConfigurationHolder {
      */
     boolean needHead();
 
+    /**
+     * Whether need automatic merge headers.
+     *
+     * @return
+     */
+    boolean automaticMergeHead();
+
     /**
      * Writes the head relative to the existing contents of the sheet. Indexes are zero-based.
      *
diff --git a/src/main/java/com/alibaba/excel/write/style/column/AbstractHeadColumnWidthStyleStrategy.java b/src/main/java/com/alibaba/excel/write/style/column/AbstractHeadColumnWidthStyleStrategy.java
index 9908144..1a88eff 100644
--- a/src/main/java/com/alibaba/excel/write/style/column/AbstractHeadColumnWidthStyleStrategy.java
+++ b/src/main/java/com/alibaba/excel/write/style/column/AbstractHeadColumnWidthStyleStrategy.java
@@ -22,7 +22,7 @@ public abstract class AbstractHeadColumnWidthStyleStrategy extends AbstractColum
         if (!needSetWidth) {
             return;
         }
-        Integer width = columnWidth(head);
+        Integer width = columnWidth(head, cell.getColumnIndex());
         if (width != null) {
             width = width * 256;
             writeSheetHolder.getSheet().setColumnWidth(cell.getColumnIndex(), width);
@@ -36,9 +36,11 @@ public abstract class AbstractHeadColumnWidthStyleStrategy extends AbstractColum
      * if return null,ignore
      *
      * @param head
-     *            Nullable
+     *            Nullable.
+     * @param columnIndex
+     *            Not null.
      * @return
      */
-    protected abstract Integer columnWidth(Head head);
+    protected abstract Integer columnWidth(Head head, Integer columnIndex);
 
 }
diff --git a/src/main/java/com/alibaba/excel/write/style/column/SimpleColumnWidthStyleStrategy.java b/src/main/java/com/alibaba/excel/write/style/column/SimpleColumnWidthStyleStrategy.java
index 1f3ae78..316ff2c 100644
--- a/src/main/java/com/alibaba/excel/write/style/column/SimpleColumnWidthStyleStrategy.java
+++ b/src/main/java/com/alibaba/excel/write/style/column/SimpleColumnWidthStyleStrategy.java
@@ -19,7 +19,7 @@ public class SimpleColumnWidthStyleStrategy extends AbstractHeadColumnWidthStyle
     }
 
     @Override
-    protected Integer columnWidth(Head head) {
+    protected Integer columnWidth(Head head, Integer columnIndex) {
         return columnWidth;
     }
 }
diff --git a/src/test/java/com/alibaba/easyexcel/test/core/fill/FillData.java b/src/test/java/com/alibaba/easyexcel/test/core/fill/FillData.java
index dcdf23f..a1dd56a 100644
--- a/src/test/java/com/alibaba/easyexcel/test/core/fill/FillData.java
+++ b/src/test/java/com/alibaba/easyexcel/test/core/fill/FillData.java
@@ -14,6 +14,6 @@ public class FillData {
     private String name;
     @NumberFormat("#")
     @ExcelProperty(converter = DoubleStringConverter.class)
-    private double number;
+    private Double number;
     private String empty;
 }
diff --git a/src/test/java/com/alibaba/easyexcel/test/core/fill/FillDataTest.java b/src/test/java/com/alibaba/easyexcel/test/core/fill/FillDataTest.java
index 93a5457..04a8bd1 100644
--- a/src/test/java/com/alibaba/easyexcel/test/core/fill/FillDataTest.java
+++ b/src/test/java/com/alibaba/easyexcel/test/core/fill/FillDataTest.java
@@ -6,35 +6,19 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
-import org.apache.poi.ss.usermodel.BorderStyle;
-import org.apache.poi.ss.usermodel.FillPatternType;
-import org.apache.poi.ss.usermodel.Font;
-import org.apache.poi.ss.usermodel.HorizontalAlignment;
-import org.apache.poi.ss.usermodel.IndexedColors;
-import org.apache.poi.ss.usermodel.VerticalAlignment;
 import org.junit.Assert;
 import org.junit.BeforeClass;
 import org.junit.FixMethodOrder;
 import org.junit.Test;
 import org.junit.runners.MethodSorters;
 
-import com.alibaba.easyexcel.test.core.style.StyleData;
-import com.alibaba.easyexcel.test.core.style.StyleDataListener;
 import com.alibaba.easyexcel.test.util.TestFileUtil;
 import com.alibaba.excel.EasyExcel;
 import com.alibaba.excel.ExcelWriter;
 import com.alibaba.excel.enums.WriteDirectionEnum;
-import com.alibaba.excel.metadata.Head;
 import com.alibaba.excel.write.merge.LoopMergeStrategy;
-import com.alibaba.excel.write.merge.OnceAbsoluteMergeStrategy;
 import com.alibaba.excel.write.metadata.WriteSheet;
 import com.alibaba.excel.write.metadata.fill.FillConfig;
-import com.alibaba.excel.write.metadata.style.WriteCellStyle;
-import com.alibaba.excel.write.metadata.style.WriteFont;
-import com.alibaba.excel.write.style.AbstractVerticalCellStyleStrategy;
-import com.alibaba.excel.write.style.HorizontalCellStyleStrategy;
-import com.alibaba.excel.write.style.column.SimpleColumnWidthStyleStrategy;
-import com.alibaba.excel.write.style.row.SimpleRowHeightStyleStrategy;
 
 /**
  *
@@ -121,7 +105,7 @@ public class FillDataTest {
 
     private void complexFill(File file, File template) {
         ExcelWriter excelWriter = EasyExcel.write(file).withTemplate(template).build();
-        WriteSheet writeSheet = EasyExcel.writerSheet().build();
+        WriteSheet writeSheet = EasyExcel.writerSheet().registerWriteHandler(new LoopMergeStrategy(2, 0)).build();
         FillConfig fillConfig = FillConfig.builder().forceNewRow(Boolean.TRUE).build();
         excelWriter.fill(data(), fillConfig, writeSheet);
         excelWriter.fill(data(), fillConfig, writeSheet);
diff --git a/src/test/java/com/alibaba/easyexcel/test/core/head/ComplexHeadDataTest.java b/src/test/java/com/alibaba/easyexcel/test/core/head/ComplexHeadDataTest.java
index f893684..25f7fed 100644
--- a/src/test/java/com/alibaba/easyexcel/test/core/head/ComplexHeadDataTest.java
+++ b/src/test/java/com/alibaba/easyexcel/test/core/head/ComplexHeadDataTest.java
@@ -18,11 +18,15 @@ public class ComplexHeadDataTest {
 
     private static File file07;
     private static File file03;
+    private static File file07AutomaticMergeHead;
+    private static File file03AutomaticMergeHead;
 
     @BeforeClass
     public static void init() {
         file07 = TestFileUtil.createNewFile("complexHead07.xlsx");
         file03 = TestFileUtil.createNewFile("complexHead03.xls");
+        file07AutomaticMergeHead = TestFileUtil.createNewFile("complexHeadAutomaticMergeHead07.xlsx");
+        file03AutomaticMergeHead = TestFileUtil.createNewFile("complexHeadAutomaticMergeHead03.xls");
     }
 
     @Test
@@ -37,6 +41,22 @@ public class ComplexHeadDataTest {
 
     private void readAndWrite(File file) {
         EasyExcel.write(file, ComplexHeadData.class).sheet().doWrite(data());
+        EasyExcel.read(file, ComplexHeadData.class, new ComplexDataListener())
+            .xlsxSAXParserFactoryName("com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl").sheet().doRead();
+    }
+
+    @Test
+    public void t03ReadAndWriteAutomaticMergeHead07() {
+        readAndWriteAutomaticMergeHead07(file07AutomaticMergeHead);
+    }
+
+    @Test
+    public void t04ReadAndWriteAutomaticMergeHead0703() {
+        readAndWriteAutomaticMergeHead07(file03AutomaticMergeHead);
+    }
+
+    private void readAndWriteAutomaticMergeHead07(File file) {
+        EasyExcel.write(file, ComplexHeadData.class).automaticMergeHead(Boolean.FALSE).sheet().doWrite(data());
         EasyExcel.read(file, ComplexHeadData.class, new ComplexDataListener()).sheet().doRead();
     }
 
diff --git a/src/test/java/com/alibaba/easyexcel/test/temp/LockTest.java b/src/test/java/com/alibaba/easyexcel/test/temp/LockTest.java
index fb39de1..27f820b 100644
--- a/src/test/java/com/alibaba/easyexcel/test/temp/LockTest.java
+++ b/src/test/java/com/alibaba/easyexcel/test/temp/LockTest.java
@@ -39,7 +39,7 @@ public class LockTest {
     @Test
     public void test2() throws Exception {
         List<Object> list =
-            EasyExcel.read(new FileInputStream("D:\\test\\null.xlsx")).sheet().headRowNumber(0).doReadSync();
+            EasyExcel.read(new FileInputStream("D:\\test\\开发部.xls")).sheet().headRowNumber(0).doReadSync();
         for (Object data : list) {
             LOGGER.info("返回数据：{}", ((Map)data).size());
             LOGGER.info("返回数据：{}", JSON.toJSONString(data));
diff --git a/update.md b/update.md
index 4b6e5a4..757de15 100644
--- a/update.md
+++ b/update.md
@@ -1,3 +1,12 @@
+# 2.1.3
+* 每个java进程单独创建一个缓存目录 [Issue #813](https://github.com/alibaba/easyexcel/issues/813)
+* 统一修改合并为unsafe，提高大量数据导出的合并的效率
+* 修改merge返回参数`relativeRowIndex`为`Integer`
+* 新增参数`automaticMergeHead` 可以设置不自动合并头 [Issue #822](https://github.com/alibaba/easyexcel/issues/822)
+* 新增参数`xlsxSAXParserFactoryName` 可以指定`SAXParserFactory`
+* 修复合并策略 空指针的问题
+* `SimpleColumnWidthStyleStrategy` 新增 参数`columnIndex`  [Issue #806](https://github.com/alibaba/easyexcel/issues/806)
+
 # 2.1.2
 * 修复强制创建新行填充，只有一行数据会未填充的bug