[Feature] add support for a custom CSVFormat

fastexcel-core/src/main/java/cn/idev/excel/metadata/csv/CsvConstant.java

@@ -0,0 +1,46 @@
+package cn.idev.excel.metadata.csv;
+
+/**
+ * Constant definitions for CSV file processing.
+ */
+public class CsvConstant {
+    /**
+     * commonly used character
+     */
+    public static final char SPACE = ' ';
+    public static final char BACKSLASH = '\\';
+    public static final char BACKSPACE = '\b';
+    public static final char PIPE = '|';
+    public static final char DOUBLE_QUOTE = '"';
+
+    /**
+     * line break
+     */
+    public static final String CR = "\r";
+    public static final String FF = "\f";
+    public static final String LF = "\n";
+    public static final String CRLF = "\r\n";
+
+    /**
+     * field related
+     */
+    public static final String TAB = "\t";
+    public static final String COMMA = ",";
+    public static final String EMPTY = "";
+    public static final String AT = "@";
+
+    /**
+     * unicode
+     */
+    public static final String UNICODE_EMPTY = "\u0000";
+    public static final String UNICODE_NEX_LINE = "\u0085";
+    public static final String UNICODE_LINE_SEPARATOR = "\u2028";
+
+    /**
+     * database NULL value
+     */
+    public static final String SQL_NULL_STRING = "\\N";
+
+    private CsvConstant() {
+    }
+}

fastexcel-core/src/main/java/cn/idev/excel/metadata/csv/CsvSheet.java

@@ -1,22 +1,13 @@
 package cn.idev.excel.metadata.csv;
 
-import java.io.Closeable;
-import java.io.IOException;
-import java.math.BigDecimal;
-import java.util.Collection;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Map;
-
+import cn.idev.excel.constant.BuiltinFormats;
 import cn.idev.excel.enums.ByteOrderMarkEnum;
 import cn.idev.excel.enums.NumericCellTypeEnum;
 import cn.idev.excel.exception.ExcelGenerateException;
 import cn.idev.excel.util.DateUtils;
 import cn.idev.excel.util.ListUtils;
 import cn.idev.excel.util.NumberDataFormatterUtils;
 import cn.idev.excel.util.StringUtils;
-import cn.idev.excel.constant.BuiltinFormats;
-
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
 import lombok.Setter;
@@ -45,6 +36,14 @@
 import org.apache.poi.ss.util.CellRangeAddress;
 import org.apache.poi.ss.util.PaneInformation;
 
+import java.io.Closeable;
+import java.io.IOException;
+import java.math.BigDecimal;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+
 /**
  * csv sheet
  *
@@ -90,7 +89,7 @@ public CsvSheet(CsvWorkbook csvWorkbook, Appendable out) {
         this.csvWorkbook = csvWorkbook;
         this.out = out;
         this.rowCacheCount = 100;
-        this.csvFormat = CSVFormat.DEFAULT;
+        this.csvFormat = csvWorkbook.getCsvFormat() == null ? CSVFormat.DEFAULT : csvWorkbook.getCsvFormat();
         this.lastRowIndex = -1;
     }
 
@@ -290,7 +289,7 @@ public List<CellRangeAddress> getMergedRegions() {
 
     @Override
     public Iterator<Row> rowIterator() {
-        return (Iterator<Row>)(Iterator<? extends Row>)rowCache.iterator();
+        return (Iterator<Row>) (Iterator<? extends Row>) rowCache.iterator();
     }
 
     @Override
@@ -761,7 +760,7 @@ public void flushData() {
                 Iterator<Cell> cellIterator = row.cellIterator();
                 int columnIndex = 0;
                 while (cellIterator.hasNext()) {
-                    CsvCell csvCell = (CsvCell)cellIterator.next();
+                    CsvCell csvCell = (CsvCell) cellIterator.next();
                     while (csvCell.getColumnIndex() > columnIndex++) {
                         csvPrinter.print(null);
                     }
@@ -807,7 +806,7 @@ private String buildCellValue(CsvCell csvCell) {
                     if (csvCell.getNumberValue() == null) {
                         return null;
                     }
-                    //number
+                    // number
                     if (dataFormat == null) {
                         dataFormat = BuiltinFormats.GENERAL;
                         dataFormatString = csvWorkbook.createDataFormat().getFormat(dataFormat);

fastexcel-core/src/main/java/cn/idev/excel/metadata/csv/CsvWorkbook.java

@@ -1,16 +1,10 @@
 package cn.idev.excel.metadata.csv;
 
-import java.io.IOException;
-import java.io.OutputStream;
-import java.nio.charset.Charset;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Locale;
-
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
 import lombok.Setter;
 import org.apache.commons.compress.utils.Lists;
+import org.apache.commons.csv.CSVFormat;
 import org.apache.poi.ss.SpreadsheetVersion;
 import org.apache.poi.ss.formula.EvaluationWorkbook;
 import org.apache.poi.ss.formula.udf.UDFFinder;
@@ -26,6 +20,13 @@
 import org.apache.poi.ss.usermodel.SheetVisibility;
 import org.apache.poi.ss.usermodel.Workbook;
 
+import java.io.IOException;
+import java.io.OutputStream;
+import java.nio.charset.Charset;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Locale;
+
 /**
  * csv workbook
  *
@@ -44,7 +45,6 @@ public class CsvWorkbook implements Workbook {
      * true if date uses 1904 windowing, or false if using 1900 date windowing.
      * <p>
      * default is false
-     *
      */
     private Boolean use1904windowing;
 
@@ -83,9 +83,14 @@ public class CsvWorkbook implements Workbook {
      * Default true.
      */
     private Boolean withBom;
+
+    /**
+     * Specifies CSVFormat for parsing.
+     */
+    private CSVFormat csvFormat;
 
     public CsvWorkbook(Appendable out, Locale locale, Boolean use1904windowing, Boolean useScientificFormat,
-        Charset charset, Boolean withBom) {
+                       Charset charset, Boolean withBom) {
         this.out = out;
         this.locale = locale;
         this.use1904windowing = use1904windowing;
@@ -196,7 +201,7 @@ public Font createFont() {
 
     @Override
     public Font findFont(boolean bold, short color, short fontHeight, String name, boolean italic, boolean strikeout,
-        short typeOffset, byte underline) {
+                         short typeOffset, byte underline) {
         return null;
     }
 
@@ -220,7 +225,7 @@ public CellStyle createCellStyle() {
         if (csvCellStyleList == null) {
             csvCellStyleList = Lists.newArrayList();
         }
-        CsvCellStyle csvCellStyle = new CsvCellStyle((short)csvCellStyleList.size());
+        CsvCellStyle csvCellStyle = new CsvCellStyle((short) csvCellStyleList.size());
         csvCellStyleList.add(csvCellStyle);
         return csvCellStyle;
     }

fastexcel-core/src/main/java/cn/idev/excel/read/builder/CsvReaderBuilder.java

@@ -0,0 +1,153 @@
+package cn.idev.excel.read.builder;
+
+import cn.idev.excel.ExcelReader;
+import cn.idev.excel.event.SyncReadListener;
+import cn.idev.excel.exception.ExcelGenerateException;
+import cn.idev.excel.read.metadata.ReadSheet;
+import cn.idev.excel.read.metadata.ReadWorkbook;
+import cn.idev.excel.support.ExcelTypeEnum;
+import org.apache.commons.csv.CSVFormat;
+import org.apache.commons.csv.QuoteMode;
+
+import java.util.List;
+
+/**
+ * Builder for CSV file reading
+ */
+public class CsvReaderBuilder extends AbstractExcelReaderParameterBuilder<CsvReaderBuilder, ReadSheet> {
+    private ReadWorkbook readWorkbook;
+    private ReadSheet readSheet;
+    private CSVFormat.Builder csvFormatBuilder;
+
+    private CsvReaderBuilder() {
+    }
+
+    public CsvReaderBuilder(ReadWorkbook readWorkbook) {
+        readWorkbook.setExcelType(ExcelTypeEnum.CSV);
+        this.readWorkbook = readWorkbook;
+        this.readSheet = new ReadSheet();
+        this.csvFormatBuilder = CSVFormat.DEFAULT.builder();
+    }
+
+    /**
+     * Sets the delimiter character
+     *
+     * @param delimiter the delimiter character
+     * @return Returns a CsvReaderBuilder object, enabling method chaining
+     */
+    public CsvReaderBuilder delimiter(String delimiter) {
+        if (delimiter != null) {
+            this.csvFormatBuilder.setDelimiter(delimiter);
+        }
+        return this;
+    }
+
+    /**
+     * Sets the quote character
+     *
+     * @param quote the quote character
+     * @return Returns a CsvReaderBuilder object, enabling method chaining
+     */
+    public CsvReaderBuilder quote(Character quote) {
+        return quote(quote, QuoteMode.MINIMAL);
+    }
+
+    /**
+     * Sets the quote character and the quoting behavior
+     *
+     * @param quote     the quote character
+     * @param quoteMode defines the quoting behavior
+     * @return Returns a CsvReaderBuilder object, enabling method chaining
+     */
+    public CsvReaderBuilder quote(Character quote, QuoteMode quoteMode) {
+        if (quote != null) {
+            this.csvFormatBuilder.setQuote(quote);
+        }
+        if (quoteMode != null) {
+            this.csvFormatBuilder.setQuoteMode(quoteMode);
+        }
+        return this;
+    }
+
+    /**
+     * Sets the line separator
+     *
+     * @param recordSeparator the line separator
+     * @return Returns a CsvReaderBuilder object, enabling method chaining
+     */
+    public CsvReaderBuilder recordSeparator(String recordSeparator) {
+        if (recordSeparator != null) {
+            this.csvFormatBuilder.setRecordSeparator(recordSeparator);
+        }
+        return this;
+    }
+
+    /**
+     * Sets the null string
+     *
+     * @param nullString the String to convert to and from {@code null}
+     * @return Returns a CsvReaderBuilder object, enabling method chaining
+     */
+    public CsvReaderBuilder nullString(String nullString) {
+        if (nullString != null) {
+            this.csvFormatBuilder.setNullString(nullString);
+        }
+        return this;
+    }
+
+    /**
+     * Sets the escape character.
+     *
+     * @param escape the Character used to escape special characters in values
+     * @return Returns a CsvReaderBuilder object, enabling method chaining
+     */
+    public CsvReaderBuilder escape(Character escape) {
+        if (escape != null) {
+            this.csvFormatBuilder.setEscape(escape);
+        }
+        return this;
+    }
+
+    private ExcelReader buildExcelReader() {
+        if (this.readWorkbook.getAutoTrim() != null) {
+            this.csvFormatBuilder.setTrim(this.readWorkbook.getAutoTrim());
+        }
+        if (this.readWorkbook.getIgnoreEmptyRow() != null) {
+            this.csvFormatBuilder.setIgnoreEmptyLines(this.readWorkbook.getIgnoreEmptyRow());
+        }
+        this.readWorkbook.setCsvFormat(this.csvFormatBuilder.build());
+        return new ExcelReader(this.readWorkbook);
+    }
+
+    public void doRead() {
+        if (this.readWorkbook == null) {
+            throw new ExcelGenerateException("Must use 'FastExcelFactory.read().csv()' to call this method");
+        }
+        ExcelReader excelReader = buildExcelReader();
+        excelReader.read(this.readSheet);
+        excelReader.finish();
+    }
+
+    /**
+     * synchronous read and returns the results
+     *
+     * @return Returns a list containing the read data
+     */
+    public <T> List<T> doReadSync() {
+        if (this.readWorkbook == null) {
+            throw new ExcelGenerateException("Must use 'FastExcelFactory.read().csv()' to call this method");
+        }
+        ExcelReader excelReader = buildExcelReader();
+        // Register a synchronous read listener
+        SyncReadListener syncReadListener = new SyncReadListener();
+        registerReadListener(syncReadListener);
+        excelReader.read(this.readSheet);
+        excelReader.finish();
+        return (List<T>) syncReadListener.getList();
+    }
+
+    @Override
+    protected ReadSheet parameter() {
+        return this.readSheet;
+    }
+}

fastexcel-core/src/main/java/cn/idev/excel/read/builder/ExcelReaderBuilder.java

@@ -263,6 +263,11 @@ public ExcelReaderSheetBuilder sheet(Integer sheetNo, String sheetName) {
         return excelReaderSheetBuilder;
     }
 
+    public CsvReaderBuilder csv() {
+        excelType(ExcelTypeEnum.CSV);
+        return new CsvReaderBuilder(parameter());
+    }
+
     @Override
     protected ReadWorkbook parameter() {
         return readWorkbook;

fastexcel-core/src/main/java/cn/idev/excel/read/metadata/ReadWorkbook.java

@@ -12,6 +12,7 @@
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
 import lombok.Setter;
+import org.apache.commons.csv.CSVFormat;
 
 import javax.xml.parsers.SAXParserFactory;
 import java.io.File;
@@ -123,4 +124,10 @@ public class ReadWorkbook extends ReadBasicParameter {
      * Ignore hidden sheet.
      */
     private Boolean ignoreHiddenSheet;
+
+    /**
+     * Specifies CSVFormat for parsing.
+     * Only work on the CSV file.
+     */
+    private CSVFormat csvFormat;
 }

fastexcel-core/src/main/java/cn/idev/excel/read/metadata/holder/csv/CsvReadWorkbookHolder.java

@@ -25,6 +25,6 @@ public class CsvReadWorkbookHolder extends ReadWorkbookHolder {
     public CsvReadWorkbookHolder(ReadWorkbook readWorkbook) {
         super(readWorkbook);
         setExcelType(ExcelTypeEnum.CSV);
-        this.csvFormat = CSVFormat.DEFAULT;
+        this.csvFormat = readWorkbook.getCsvFormat() == null ? CSVFormat.DEFAULT : readWorkbook.getCsvFormat();
     }
 }