Merge pull request #1052 from alibaba/2.1.fix

2.1.fix

README.md

@@ -7,6 +7,7 @@ easyexcel
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 [官方网站: https://alibaba-easyexcel.github.io/](https://alibaba-easyexcel.github.io/)
+#### 因为公司不方便用QQ，所以建议加钉钉群
 
 # JAVA解析Excel工具easyexcel
 Java解析、生成Excel比较有名的框架有Apache poi、jxl。但他们都存在一个严重的问题就是非常的耗内存，poi有一套SAX模式的API可以一定程度的解决一些内存溢出的问题，但POI还是有一些缺陷，比如07版Excel解压缩以及解压后存储都是在内存中完成的，内存消耗依然很大。easyexcel重写了poi对07版Excel的解析，能够原本一个3M的excel用POI sax依然需要100M左右内存降低到几M，并且再大的excel不会出现内存溢出，03版依赖POI的sax模式。在上层做了模型转换的封装，让使用者更加简单方便

pom.xml

@@ -4,7 +4,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.alibaba</groupId>
     <artifactId>easyexcel</artifactId>
-    <version>2.1.5</version>
+    <version>2.1.6</version>
     <packaging>jar</packaging>
     <name>easyexcel</name>
 

src/main/java/com/alibaba/excel/context/WriteContextImpl.java

@@ -161,14 +161,10 @@ public class WriteContextImpl implements WriteContext {
                     .setCachedSheet(writeWorkbookHolder.getCachedWorkbook().getSheet(writeSheetHolder.getSheetName()));
             }
         } catch (Exception e) {
-            if (LOGGER.isDebugEnabled()) {
-                LOGGER.debug("Can not find sheet:{} ,now create it", writeSheetHolder.getSheetNo());
-            }
-            if (StringUtils.isEmpty(writeSheetHolder.getSheetName())) {
-                writeSheetHolder.setSheetName(writeSheetHolder.getSheetNo().toString());
+            currentSheet = createSheet();
         }
-            currentSheet = WorkBookUtil.createSheet(writeWorkbookHolder.getWorkbook(), writeSheetHolder.getSheetName());
-            writeSheetHolder.setCachedSheet(currentSheet);
+        if (currentSheet == null) {
+            currentSheet = createSheet();
         }
         writeSheetHolder.setSheet(currentSheet);
         WriteHandlerUtils.afterSheetCreate(this);
@@ -180,6 +176,19 @@ public class WriteContextImpl implements WriteContext {
         writeWorkbookHolder.getHasBeenInitializedSheetNameMap().put(writeSheetHolder.getSheetName(), writeSheetHolder);
     }
 
+    private Sheet createSheet() {
+        if (LOGGER.isDebugEnabled()) {
+            LOGGER.debug("Can not find sheet:{} ,now create it", writeSheetHolder.getSheetNo());
+        }
+        if (StringUtils.isEmpty(writeSheetHolder.getSheetName())) {
+            writeSheetHolder.setSheetName(writeSheetHolder.getSheetNo().toString());
+        }
+        Sheet currentSheet =
+            WorkBookUtil.createSheet(writeWorkbookHolder.getWorkbook(), writeSheetHolder.getSheetName());
+        writeSheetHolder.setCachedSheet(currentSheet);
+        return currentSheet;
+    }
+
     public void initHead(ExcelWriteHeadProperty excelWriteHeadProperty) {
         if (!currentWriteHolder.needHead() || !currentWriteHolder.excelWriteHeadProperty().hasHead()) {
             return;

update.md

@@ -1,3 +1,6 @@
+# 2.1.6
+* 修复写入只有`sheetName`会抛异常
+
 # 2.1.5
 * 修复部分xlsx没有行号读取异常
 * 填充时候支持根据`sheetName`定位`sheet`