1. 单元格类型
单元格的内容决定了单元格的类型，POI中定义的7种单元格类型：
- 日期数据对应的单元格类型是CellType.NUMERIC，默认以浮点型数显示，显示为日期格式需要设置单元格样式DataFormat
- 字符型单元格内容也可以为富文本RichTextString，可以对文本多部分设置字体Font
2. 错误单元格
Excel中存在错误单元格，在POI中是怎么表现的呢
org.apache.poi.ss.usermodel.FormulaError1
package org.apache.poi.ss.usermodel; import java.util.Map; import org.apache.poi.util.Internal; import java.util.HashMap; /** * Enumerates error values in SpreadsheetML formula calculations. * * See also OOO's excelfileformat.pdf (2.5.6) */
public enum FormulaError { @Internal _NO_ERROR(-1, "(no error)"), /** * Intended to indicate when two areas are required to intersect, but do not. * <p>Example: * In the case of SUM(B1 C1), the space between B1 and C1 is treated as the binary * intersection operator, when a comma was intended. end example] * </p> */ NULL(0x00, "#NULL!"), /** * Intended to indicate when any number, including zero, is divided by zero. * Note: However, any error code divided by zero results in that error code. */ DIV0(0x07, "#DIV/0!"), /** * Intended to indicate when an incompatible type argument is passed to a function, or * an incompatible type operand is used with an operator. * <p>Example: * In the case of a function argument, text was expected, but a number was provided * </p> */ VALUE(0x0F, "#VALUE!"), /** * Intended to indicate when a cell reference is invalid. * <p>Example: * If a formula contains a reference to a cell, and then the row or column containing that cell is deleted, * a #REF! error results. If a worksheet does not support 20,001 columns, * OFFSET(A1,0,20000) will result in a #REF! error. * </p> */ REF(0x17, "#REF!"), /** * Intended to indicate when what looks like a name is used, but no such name has been defined. * <p>Example: * XYZ/3, where XYZ is not a defined name. Total is & A10, * where neither Total nor is is a defined name. Presumably, "Total is " & A10 * was intended. SUM(A1C10), where the range A1:C10 was intended. * </p> */ NAME(0x1D, "#NAME?"), /** * Intended to indicate when an argument to a function has a compatible type, but has a * value that is outside the domain over which that function is defined. (This is known as * a domain error.) * <p>Example: * Certain calls to ASIN, ATANH, FACT, and SQRT might result in domain errors. * </p> * Intended to indicate that the result of a function cannot be represented in a value of * the specified type, typically due to extreme magnitude. (This is known as a range * error.) * <p>Example: FACT(1000) might result in a range error. </p> */ NUM(0x24, "#NUM!"), /** * Intended to indicate when a designated value is not available. * <p>Example: * Some functions, such as SUMX2MY2, perform a series of operations on corresponding * elements in two arrays. If those arrays do not have the same number of elements, then * for some elements in the longer array, there are no corresponding elements in the * shorter one; that is, one or more values in the shorter array are not available. * </p> * This error value can be produced by calling the function NA */ NA(0x2A, "#N/A"), // These are POI-specific error codes // It is desirable to make these (arbitrary) strings look clearly different from any other // value expression that might appear in a formula. In addition these error strings should // look unlike the standard Excel errors. Hence tilde ('~') was used. /** * POI specific code to indicate that there is a circular reference * in the formula */ CIRCULAR_REF(0xFFFFFFC4, "~CIRCULAR~REF~"), /** * POI specific code to indicate that the funcition required is * not implemented in POI */ FUNCTION_NOT_IMPLEMENTED(0xFFFFFFE2, "~FUNCTION~NOT~IMPLEMENTED~"); private final byte type; private final int longType; private final String repr; private FormulaError(int type, String repr) { this.type = (byte)type; this.longType = type; this.repr = repr; } /** * @return numeric code of the error */ public byte getCode() { return type; } /** * @return long (internal) numeric code of the error */ public int getLongCode() { return longType; } /** * @return string representation of the error */ public String getString() { return repr; } private static final Map<String, FormulaError> smap = new HashMap<String, FormulaError>(); private static final Map<Byte, FormulaError> bmap = new HashMap<Byte, FormulaError>(); private static final Map<Integer, FormulaError> imap = new HashMap<Integer, FormulaError>(); static{ for (FormulaError error : values()) { bmap.put(error.getCode(), error); imap.put(error.getLongCode(), error); smap.put(error.getString(), error); } } public static final boolean isValidCode(int errorCode) { for (FormulaError error : values()) { if (error.getCode() == errorCode) return true; if (error.getLongCode() == errorCode) return true; } return false; } public static FormulaError forInt(byte type) throws IllegalArgumentException { FormulaError err = bmap.get(type); if(err == null) throw new IllegalArgumentException("Unknown error type: " + type); return err; } public static FormulaError forInt(int type) throws IllegalArgumentException { FormulaError err = imap.get(type); if(err == null) err = bmap.get((byte)type); if(err == null) throw new IllegalArgumentException("Unknown error type: " + type); return err; } public static FormulaError forString(String code) throws IllegalArgumentException { FormulaError err = smap.get(code); if(err == null) throw new IllegalArgumentException("Unknown error code: " + code); return err; }
}
3. 实例
package hssf.sheet.cell;import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Calendar;
import java.util.Date;import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.CellType;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;public class ExportDataCell {public static void main(String[] args) throws Exception {File file = new File("C:\\Users\\Administrator\\Desktop\\test.xls");if (file.exists()) {file.delete();}BufferedOutputStream out = null;try {out = new BufferedOutputStream(new FileOutputStream("C:\\Users\\Administrator\\Desktop\\test.xls"));exportExcel(out);} finally {out.close();}}private static void exportExcel(BufferedOutputStream out) throws IOException {Workbook wb = new HSSFWorkbook();//Workbook wb = new XSSFWorkbook();Sheet sheet = wb.createSheet("各种类型单元格");sheet.createRow(0).createCell(0).setCellValue(1.1);sheet.createRow(1).createCell(0).setCellValue(new Date());sheet.createRow(2).createCell(0).setCellValue(Calendar.getInstance());sheet.createRow(3).createCell(0).setCellValue("字符串");sheet.createRow(4).createCell(0).setCellValue(true);sheet.createRow(5).createCell(0).setCellType(CellType.ERROR);wb.write(out);}
}
