原题链接在这里：https://leetcode.com/problems/excel-sheet-column-number/ 这道题与Excel Sheet Column Title相呼应。Time O(n), Space O(1). 注意cast时后面的数要加个整体的括号。 AC Java: public class Solution { public int titleToNumber(Strin

这里的代码是介绍使用poi复制一个sheet到另一个excel的sheet中，具体请下如下代码； import java.util.HashMap;import java.util.Map;import java.util.Set;import java.util.TreeSet;import org.apache.poi.hssf.usermodel.HSSFCell;import org.apache.poi.hssf.usermodel.HSSFCellStyle;import org.apache.poi.hssf.usermodel.HSSFRow;import org.apache.poi.hssf.usermodel.HSSFSheet;import org.apache.poi.ss.util.CellRangeAddress;/** *

* @author trx */public final class CopySheetUtil {

public CopySheetUtil() {

}

public static void copySheets(HSSFSheet newSheet, HSSFSheet sheet) {

copySheets(newSheet, sheet, true);

}

public static void copySheets(HSSFSheet newSheet, HSSFSheet sheet,

boolean copyStyle) {

int maxColumnNum = 0;

Map styleMap = (copyStyle) ? new HashMap()

: null;

for (int i = sheet.getFirstRowNum(); i <= sheet.getLastRowNum(); i++) {

HSSFRow srcRow = sheet.getRow(i);

HSSFRow destRow = newSheet.createRow(i);

if (srcRow != null) {

CopySheetUtil.copyRow(sheet, newSheet, srcRow, destRow,

styleMap);

if (srcRow.getLastCellNum() > maxColumnNum) {

maxColumnNum = srcRow.getLastCellNum();

}

}

}

for (int i = 0; i <= maxColumnNum; i++) {

//设置列宽

newSheet.setColumnWidth(i, sheet.getColumnWidth(i));

}

}

/**

* 复制并合并单元格

* @param newSheet

* @param sheet

* @param copyStyle

*/

public static void copyRow(HSSFSheet srcSheet, HSSFSheet destSheet,

HSSFRow srcRow, HSSFRow destRow,

Map styleMap) {

Set mergedRegions = new TreeSet();

destRow.setHeight(srcRow.getHeight());

int deltaRows = destRow.getRowNum() - srcRow.getRowNum(); //如果copy到另一个sheet的起始行数不同

for (int j = srcRow.getFirstCellNum(); j <= srcRow.getLastCellNum(); j++) {

HSSFCell oldCell = srcRow.getCell(j); // old cell

HSSFCell newCell = destRow.getCell(j); // new cell

if (oldCell != null) {

if (newCell == null) {

newCell = destRow.createCell(j);

}

copyCell(oldCell, newCell, styleMap);

CellRangeAddress mergedRegion = getMergedRegion(srcSheet,

srcRow.getRowNum(), (short) oldCell.getColumnIndex());

if (mergedRegion != null) {

CellRangeAddress newMergedRegion = new CellRangeAddress(

mergedRegion.getFirstRow() + deltaRows,

mergedRegion.getLastRow() + deltaRows, mergedRegion

.getFirstColumn(), mergedRegion

.getLastColumn());

CellRangeAddressWrapper wrapper = new CellRangeAddressWrapper(

newMergedRegion);

if (isNewMergedRegion(wrapper, mergedRegions)) {

mergedRegions.add(wrapper);

destSheet.addMergedRegion(wrapper.range);

}

}

}

}

}

/**

* 把原来的Sheet中cell(列)的样式和数据类型复制到新的sheet的cell(列)中

*

* @param oldCell

* @param newCell

* @param styleMap

*/

public static void copyCell(HSSFCell oldCell, HSSFCell newCell,

Map styleMap) {

if (styleMap != null) {

if (oldCell.getSheet().getWorkbook() == newCell.getSheet()

.getWorkbook()) {

newCell.setCellStyle(oldCell.getCellStyle());

} else {

int stHashCode = oldCell.getCellStyle().hashCode();

HSSFCellStyle newCellStyle = styleMap.get(stHashCode);

if (newCellStyle == null) {

newCellStyle = newCell.getSheet().getWorkbook()

.createCellStyle();

newCellStyle.cloneStyleFrom(oldCell.getCellStyle());

styleMap.put(stHashCode, newCellStyle);

}

newCell.setCellStyle(newCellStyle);

}

}

switch (oldCell.getCellType()) {

case HSSFCell.CELL_TYPE_STRING:

newCell.setCellValue(oldCell.getStringCellValue());

break;

case HSSFCell.CELL_TYPE_NUMERIC:

newCell.setCellValue(oldCell.getNumericCellValue());

break;

case HSSFCell.CELL_TYPE_BLANK:

newCell.setCellType(HSSFCell.CELL_TYPE_BLANK);

break;

case HSSFCell.CELL_TYPE_BOOLEAN:

newCell.setCellValue(oldCell.getBooleanCellValue());

break;

case HSSFCell.CELL_TYPE_ERROR:

newCell.setCellErrorValue(oldCell.getErrorCellValue());

break;

case HSSFCell.CELL_TYPE_FORMULA:

newCell.setCellFormula(oldCell.getCellFormula());

break;

default:

break;

}

}

// 获取merge对象

public static CellRangeAddress getMergedRegion(HSSFSheet sheet, int rowNum,

short cellNum) {

for (int i = 0; i < sheet.getNumMergedRegions(); i++) {

CellRangeAddress merged = sheet.getMergedRegion(i);

if (merged.isInRange(rowNum, cellNum)) {

return merged;

}

}

return null;

}

private static boolean isNewMergedRegion(

CellRangeAddressWrapper newMergedRegion,

Set mergedRegions) {

boolean bool = mergedRegions.contains(newMergedRegion);

return !bool;

}}

接着再写一个实现类如下： import org.apache.poi.ss.util.CellRangeAddress;public class CellRangeAddressWrapper implements Comparable {

public CellRangeAddress range;

public CellRangeAddressWrapper(CellRangeAddress theRange) {

this.range = theRange;

}

public int compareTo(CellRangeAddressWrapper craw) {

if (range.getFirstColumn() < craw.range.getFirstColumn()

&& range.getFirstRow() < craw.range.getFirstRow()) {

return -1;

} else if (range.getFirstColumn() == craw.range.getFirstColumn()

&& range.getFirstRow() == craw.range.getFirstRow()) {

return 0;

} else {

return 1;

}

}

}

到此代码结束