poi解析excel，将每一行数据注入到对应的entity实体对象对象中

20190723更新一个bug

1. 在getValueFromCell()方法中
   String typeName = expectClazz.getTypeName();
   变更为
   String typeName = expectClazz.getSimpleName();
2. 同时增加支持类型限制，也就是其中的supportTypeList，表达了该工具类支持excel中的数据类型

贼好用的代码，直接上辽

依赖给上

			org.apache.poi
			poi
			3.11
		
		
			org.apache.poi
			poi-ooxml
			3.11
		
		
			org.apache.poi
			poi-ooxml-schemas
			3.11
		

/**测试用的实体类**/
public class GameScene {
    public int id;
    public String name;


    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public void setId(int id) {
        this.id = id;
    }

    public int getId() {
        return id;
    }

    @Override
    public String toString() {
        return "GameScene{" +
                "id=" + id +
                ", name='" + name + '\'' +
                '}';
    }
}

//取出方法引用
public class Ref {
    public T ref;

    public T getRef() {
        return ref;
    }

    public void setRef(T ref) {
        this.ref = ref;
    }
}

package org.sq.gameDemo.svr.common;

import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.ss.usermodel.Row;
import org.sq.gameDemo.svr.game.skills.model.Skill;

import java.io.*;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
import java.util.*;

public class PoiUtil {

    public static List supportTypeList =
            Arrays.asList("int", "Integer", "float", "Float", "long", "Long", "double", "Double", "String");

    /**
     * 主方法
     * @param fileName excel文件流
     * @param sheetNum 第sheetNum个表格
     * @param clazz 实体class
     * @return
     * @throws Exception
     */
    public static List readExcel(String fileName, int sheetNum, Class clazz) throws Exception{
        //1.读取Excel文档对象
        //将class的Field的名称记录到map中
        Map setMethodMap = new HashMap<>();
        for (Field field : clazz.getDeclaredFields()) {
            String name = field.getName();
            if(supportTypeList.contains(field.getType().getSimpleName())) {
                try{
                    Method setMethod = clazz.getDeclaredMethod(
                            "set" + String.valueOf(name.charAt(0)).toUpperCase()+ field.getName().substring(1),
                            field.getType());
                    setMethodMap.put(name, setMethod);
                }catch (NoSuchMethodException e) {
                    continue;
                }

            }
        }

        ArrayList excelData = new ArrayList<>();
        HSSFWorkbook hssfWorkbook = null;
        try {
            File file = new File(fileName);
            InputStream resourceAsStream = PoiUtil.class.getClassLoader().getResourceAsStream(fileName);
            hssfWorkbook = new HSSFWorkbook(resourceAsStream);
            HSSFSheet sheet = hssfWorkbook.getSheetAt(sheetNum);
            int lastRowNum = sheet.getLastRowNum();
            //Ref为了将第一行标题取出来
            Ref listRef = new Ref<>();
            getSingleRow(sheet, 0, setMethodMap, listRef, clazz);//<1,name>

            //将每一行的数据注入到class实例中并保存在list中
            for(int i = 1;i <= lastRowNum; i++) {
                try {
                    Object singleRow = getSingleRow(sheet, i, setMethodMap, listRef, clazz);
                    excelData.add(singleRow);
                }catch (Exception e) {
                    throw new Exception("该路径下 " + file.getPath() + " 文件内容有誤");
                }
            }
            return excelData;
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 根据传入的clazz 将每一行的数据填充到clazz.instance的实例中，然后返回
     * @param sheet
     * @param rowNum 取第rownum行
     * @param setMethod class中所有属性对应set属性方法的map映射；譬如class类中 public String name; 就会有-> 
     * @param listRef 引用，从参数取方法中的某个局部变量的引用
     * @param clazz 实例类变量
     * @return
     * @throws InstantiationException
     * @throws IllegalAccessException
     * @throws InvocationTargetException
     * @throws NoSuchFieldException
     */
    private static Object getSingleRow(HSSFSheet sheet, int rowNum, Map setMethod, Ref listRef, Class clazz) throws Exception {
        HSSFRow row = sheet.getRow(rowNum);

        if(!checkRow(row, rowNum, setMethod)) {
            System.out.println("err: 第" + (rowNum + 1) + "行數據有误");
            throw new Exception("PoiUtil -> excel文件有誤");
        }

        //此次读取是否为标题行读取
        boolean titleRow = (rowNum == 0 && Objects.isNull(listRef.ref));
        List