POI读取excel文件通用代码（增强版--支持返回javaBean集合）---2003,2007

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;

import net.sf.json.JSONObject;

import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.apache.poi2.hssf.usermodel.HSSFCell;
import org.apache.poi2.hssf.usermodel.HSSFRow;
import org.apache.poi2.hssf.usermodel.HSSFSheet;
import org.apache.poi2.hssf.usermodel.HSSFWorkbook;

public class ExcelUtil {

private ExcelUtil(){};
private static List<String> columns;//要解析excel中的列名
private static int sheetNum = 0;//要解析的sheet下标
/**
* poi读取excle
* @return
*/
public static String readExcel(File file){
StringBuilder retJson = new StringBuilder();
InputStream inStream = null;
try {
inStream = new FileInputStream(file);
HSSFWorkbook workbook = new HSSFWorkbook(inStream);
HSSFSheet sheet = workbook.getSheetAt(sheetNum);//获得表
int lastRowNum = sheet.getLastRowNum();//最后一行
retJson.append("[");
for(int i = 0 ;i < lastRowNum;i++){
HSSFRow row = sheet.getRow(i);//获得行
String rowJson = readExcelRow(row);
retJson.append(rowJson);
if(i<lastRowNum-1)
retJson.append(",");
}
retJson.append("]");
} catch (Exception e) {
try {
inStream = new FileInputStream(file);
XSSFWorkbook workbook = new XSSFWorkbook(inStream);
XSSFSheet sheet = workbook.getSheetAt(sheetNum);
int lastRowNum = sheet.getLastRowNum();//最后一行
retJson.append("[");
for(int i = 0 ;i < lastRowNum;i++){
XSSFRow row = sheet.getRow(i);//获得行
String rowJson = readExcelRow(row);
retJson.append(rowJson);
if(i<lastRowNum-1)
retJson.append(",");
}
retJson.append("]");
} catch (IOException e1) {
e1.printStackTrace();
}
}finally{
close(null,inStream);
}
return retJson.toString();
}
/**
* poi读取excle 生成实体集合
* @param <E>
* @return
*/
public static <E> List<E> readExcel(File file,Class<E> clazz){

InputStream inStream = null;
List<E> eList = new ArrayList<E>();
try {
inStream = new FileInputStream(file);
HSSFWorkbook workbook = new HSSFWorkbook(inStream);
HSSFSheet sheet = workbook.getSheetAt(sheetNum);//获得表
int lastRowNum = sheet.getLastRowNum();//最后一行
for(int i = 1 ;i < lastRowNum;i++){
HSSFRow row = sheet.getRow(i);//获得行
String rowJson = readExcelRow(row);
E _e = json2Bean(rowJson,clazz);
eList.add(_e);
}
} catch (Exception e) {
try {
inStream = new FileInputStream(file);
XSSFWorkbook workbook = new XSSFWorkbook(inStream);
XSSFSheet sheet = workbook.getSheetAt(sheetNum);
int lastRowNum = sheet.getLastRowNum();//最后一行
for(int i = 1 ;i < lastRowNum;i++){
XSSFRow row = sheet.getRow(i);//获得行
String rowJson = readExcelRow(row);
E _e = json2Bean(rowJson,clazz);
eList.add(_e);
}
} catch (Exception e1) {
e1.printStackTrace();
}
}finally{
close(null,inStream);
}
return eList;
}
/**
* 将json转换为Bean实例
* @param <E>
* @return
*/
private static <E> E json2Bean(String json,Class<E> clazz){
JSONObject jsonObj = JSONObject.fromObject(json);
Method[] methods = clazz.getDeclaredMethods();
try {
E _e = clazz.newInstance();
for(Method m:methods){
String name = m.getName();
if(name.startsWith("set")){
String keyPrev = name.substring(3,4).toLowerCase();
String keyNext = name.substring(4);
String val = "";
try {
val = jsonObj.getString(keyPrev+keyNext);
} catch (Exception e) {
val = "";
}
m.invoke(_e, val);
}
}
return _e;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
/**
* 读取行值
* @return
*/
private static String readExcelRow(HSSFRow row){
StringBuilder rowJson = new StringBuilder();
int lastCellNum = ExcelUtil.columns.size();//最后一个单元格
rowJson.append("{");
for(int i = 0 ;i<lastCellNum;i++){
HSSFCell cell = row.getCell(i);
String cellVal = readCellValue(cell);
rowJson.append(toJsonItem(columns.get(i), cellVal));
if(i<lastCellNum-1)
rowJson.append(",");
}
rowJson.append("}");
return rowJson.toString();
}
/**
* 读取行值
* @return
*/
private static String readExcelRow(XSSFRow row){
StringBuilder rowJson = new StringBuilder();
int lastCellNum = ExcelUtil.columns.size();//最后一个单元格
rowJson.append("{");
for(int i = 0 ;i<lastCellNum;i++){
XSSFCell cell = row.getCell(i);
String cellVal = readCellValue(cell);
rowJson.append(toJsonItem(columns.get(i), cellVal));
if(i<lastCellNum-1)
rowJson.append(",");
}
rowJson.append("}");
return rowJson.toString();
}

/**
* 读取单元格的值
* @param hssfCell
* @return
*/
@SuppressWarnings("static-access")
private static String readCellValue(HSSFCell hssfCell) {
if (hssfCell.getCellType() == hssfCell.CELL_TYPE_BOOLEAN) {
return String.valueOf(hssfCell.getBooleanCellValue());
} else if (hssfCell.getCellType() == hssfCell.CELL_TYPE_NUMERIC) {
hssfCell.setCellType(1);//设置为String
String str_temp = String.valueOf(hssfCell.getRichStringCellValue());//得到值
return str_temp;
}else if(hssfCell.getCellType() == hssfCell.CELL_TYPE_FORMULA){
int val = hssfCell.getCachedFormulaResultType();
return val+"";
} else {
return String.valueOf(hssfCell.getRichStringCellValue());
}
}
/**
* 读取单元格的值
* @param hssfCell
* @return
*/
@SuppressWarnings("static-access")
private static String readCellValue(XSSFCell sssfCell) {
if (sssfCell.getCellType() == sssfCell.CELL_TYPE_BOOLEAN) {
return String.valueOf(sssfCell.getBooleanCellValue());
} else if (sssfCell.getCellType() == sssfCell.CELL_TYPE_NUMERIC) {
sssfCell.setCellType(1);//设置为String
String str_temp = String.valueOf(sssfCell.getRichStringCellValue());//得到值
return str_temp;
}else if(sssfCell.getCellType() == sssfCell.CELL_TYPE_FORMULA){
int val = sssfCell.getCachedFormulaResultType();
return val+"";
}else {
return String.valueOf(sssfCell.getRichStringCellValue());
}
}
/**
* 转换为json对
* @return
*/
private static String toJsonItem(String name,String val){
return "\""+name+"\":\""+val+"\"";
}
/**
* 关闭io流
* @param fos
* @param fis
*/
private static void close(OutputStream out, InputStream in) {
if (in != null) {
try {
in.close();
} catch (IOException e) {
System.out.println("InputStream关闭失败");
e.printStackTrace();
}
}
if (out != null) {
try {
out.close();
} catch (IOException e) {
System.out.println("OutputStream关闭失败");
e.printStackTrace();
}
}
}
public static List<String> getColumns() {
return ExcelUtil.columns;
}
public static void setColumns(List<String> columns) {
ExcelUtil.columns = columns;
}
public static int getSheetNum() {
return sheetNum;
}
public static void setSheetNum(int sheetNum) {
ExcelUtil.sheetNum = sheetNum;
}

} http://javasam.iteye.com/blog/2121540