java中，list集合資料匯出到excel表格通用工具類
阿新 • • 發佈：2019-01-03
1.建立CustomTag類（實體類class自定義欄位名稱註解類）
package CzExcel;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
/**
* 實體類class欄位名稱註解類
* @author xgf
*
*/
@Retention(RetentionPolicy.RUNTIME)
public @interface CustomTag {
//欄位的描述註解
String desc();
}
2.建立CustomTagMethod類（實體類自定義方法註解類）
package CzExcel;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
/**
* 實體類方法註解類
* @author xgf
*
*/
@Retention(RetentionPolicy.RUNTIME)
public @interface CustomTagMethod {
//欄位的描述註解
String name();
}
3.建立CustomTagClass類（實體類class名稱自定義註解類）
package CzExcel; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; /** * 實體類class名稱註解類 * @author xgf * */ @Retention(RetentionPolicy.RUNTIME) public @interface CustomTagClass { //欄位的描述註解 String name(); }
4.建立ClassUtil類（實體類操作工具類）
package CzExcel; import java.lang.annotation.Annotation; import java.lang.reflect.Field; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.util.HashMap; import java.util.Map; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * 實體類操作工具類 * @author xgf * */ public class ClassUtil { private static Logger logger = LoggerFactory.getLogger(ClassUtil.class); /** * 通過屬性取得屬性的描述註解 * * @param field * @return */ public static String getDesc(Field field) { String result = null; try { field.setAccessible(true); Annotation[] annotation = field.getAnnotations(); for (Annotation tag : annotation) { if (tag instanceof CustomTag) { result = ((CustomTag) tag).desc(); break; } } } catch (SecurityException e) { logger.error(e.getMessage()); e.printStackTrace(); } return result; // return getAnnotation(DESC, field); // return getAnnotation(field); } /** * 通過物件和屬性名稱取得屬性的描述註解 * * @param obj * @param propertyName * @return */ public static String getDesc(Object obj, String propertyName) { String result = null; try { Field[] fields = obj.getClass().getDeclaredFields(); for (Field field : fields) { field.setAccessible(true); if (field.getName().equals(propertyName)) { String desc = getDesc(field); if (desc != null && !desc.isEmpty()) { result = desc; break; } } } } catch (SecurityException e) { logger.error(e.getMessage()); e.printStackTrace(); } return result; } /** * 取得obj所有屬性的描述註解，返回值為key為obj的屬性名稱,value為此屬性的描述註解 * * @param obj * @return */ public static Map<String, String> getAllDesc(Object obj) { try { Field[] fields = obj.getClass().getDeclaredFields(); return getResult(fields); } catch (SecurityException e) { logger.error(e.getMessage()); e.printStackTrace(); } return null; } /** * 取得obj所有屬性的描述註解，返回值為key為obj的屬性名稱,value為此屬性的描述註解 * * @param obj * @return */ public static Map<String, String> getAllDesc(String clzName) { try { Field[] fields = Class.forName(clzName).getDeclaredFields(); return getResult(fields); } catch (SecurityException e) { logger.error(e.getMessage()); e.printStackTrace(); } catch (ClassNotFoundException e) { logger.error(e.getMessage()); e.printStackTrace(); } return null; } /** * 將field[]裡的欄位名稱做為key和欄位描述做value放在map中 * * @param fields * @param map */ private static Map<String, String> getResult(Field[] fields) { Map<String, String> result = new HashMap<String, String>(); for (Field field : fields) { field.setAccessible(true); if (field.getName().equals("id")) { continue; } String desc = getDesc(field); if (desc != null && !desc.isEmpty()) { result.put(field.getName(), getDesc(field)); } } return result; } public static String getClassName(Class<?> class1){ //獲取類上的註解值 CustomTagClass anno = class1.getAnnotation(CustomTagClass.class); if(anno != null){ Method[] met = anno.annotationType().getDeclaredMethods(); for(Method me : met ){ if(!me.isAccessible()){ me.setAccessible(true); } try { return (String) me.invoke(anno, null); } catch (IllegalAccessException e) { e.printStackTrace(); } catch (IllegalArgumentException e) { e.printStackTrace(); } catch (InvocationTargetException e) { e.printStackTrace(); } } } return ""; } }
5.建立Model類（自定義實體類）
package CzExcel;
import java.sql.Timestamp;
import java.util.Date;
/**
* 實體類
* @author xgf
*
*/
@CustomTagClass(name="測試類")
public class Model {
@CustomTag(desc="名稱")
private String mc;
@CustomTag(desc="日期")
private Date rq;
@CustomTag(desc="時間")
private Timestamp sj;
@CustomTag(desc="類別")
private String type;
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public String getMc() {
return mc;
}
public void setMc(String mc) {
this.mc = mc;
}
public Date getRq() {
return rq;
}
public void setRq(Date rq) {
this.rq = rq;
}
public Timestamp getSj() {
return sj;
}
public void setSj(Timestamp sj) {
this.sj = sj;
}
}
6.建立MapKeyComparator類（map排序比較器類）
package CzExcel;
import java.util.Comparator;
import java.util.Map;
import java.util.TreeMap;
/**
* map排序比較器類
* @author xgf
*
*/
public class MapKeyComparator implements Comparator<String>{
@Override
public int compare(String str1, String str2) {
return str1.compareTo(str2);
}
/**
* 使用 Map按key進行排序
* @param map
* @return
*/
public static Map<String, Object> sortMapByKey(Map<String, Object> map) {
if (map == null || map.isEmpty()) {
return null;
}
Map<String, Object> sortMap = new TreeMap<String, Object>(
new MapKeyComparator());
sortMap.putAll(map);
return sortMap;
}
}
7.建立ExportExcel類（list集合資料匯出到excel表格中通用工具類）
package CzExcel;
import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.lang.reflect.Method;
import java.sql.Timestamp;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.commons.lang.StringUtils;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* list資料匯出到excel表格中工具類
* @author xgf
*
*/
public class ExportExcel
{
private static Logger logger = LoggerFactory.getLogger(ExportExcel.class);
/**
* 資料轉換
* @param list 資料
* @param fileName 檔案地址
* @param type 是否需要排序：1需要排序，2不需要排序
* @param headersNew 排序欄位
*/
public static void exportExcelUtil(List<?> list,String fileName,String type,String[] headersNew,Object obj) {
try {
//List<Model>轉List<Map>
List<Map> dataset=new ArrayList<Map>();
Map<String,String> mapPx=new HashMap<String,String>();//獲取排序陣列下標
for (int i = 0; i < headersNew.length; i++) {
mapPx.put(headersNew[i], i+"");
}
for (int i = 0; i < list.size(); i++) {
if(type.equals("1")){
Map map=transBean2Map(list.get(i));
Map mapNew=new HashMap<>();
for (Object key : map.keySet()) {
mapNew.put(mapPx.get(key.toString()), map.get(key));
}
mapNew=MapKeyComparator.sortMapByKey(mapNew);
dataset.add(mapNew);
}else{
dataset.add(transBean2Map(list.get(i)));
}
}
//獲取表頭
Map<String,String> map = ClassUtil.getAllDesc(obj);
//設定excel表頭
//String[] headers={"mc","rq","sj"};
String[] headers=null;
Object[] keys = map.keySet().toArray();//從實體類中取欄位
String[] headersZd=new String[keys.length];
for (int i = 0; i < keys.length; i++) {
headersZd[i]=keys[i].toString();
}
if(type.equals("1")){
headers=headersNew;
}else{
headers=headersZd;
}
String[] headersTitle=null;
Object[] keysTitle = map.values().toArray();//從實體類中取欄位註釋
String[] headersTitleZs=new String[keysTitle.length];
for (int i = 0; i < keysTitle.length; i++) {
headersTitleZs[i]=keysTitle[i].toString();
}
if(type.equals("1")){
Map<String,String> mapZs=new HashMap<String,String>();
for (int i = 0; i < headersZd.length; i++) {
mapZs.put(headersZd[i], headersTitleZs[i]);
}
headersTitle=new String[headersTitleZs.length];
for (int i = 0; i < headers.length; i++) {
headersTitle[i]=mapZs.get(headers[i]);
}
}else{
headersTitle=headersTitleZs;
}
//獲取類上的註解值
String title=ClassUtil.getClassName(obj.getClass());
if(StringUtils.isNotBlank(title)==false){
title="Sheet1";
}
exportExcel(fileName,title,headers,headersTitle,dataset,"yyyy-MM-dd","2");
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 把內容寫入excel表格中
* @param fileName 檔案地址
* @param title excel表格工作空間名稱
* @param headers 表格列欄位
* @param headersTitle 表格表頭中文欄位
* @param dataset 資料
* @param pattern 日期、時間格式化輸出
* @param type 表格表頭展示方式：1實體類欄位名，2實體類欄位名註釋
* @return
*/
public static boolean exportExcel(String fileName, String title, String[] headers,String[] headersTitle, List<Map> dataset, String pattern,String type)
{
boolean flag = false;
Workbook workbook = null;
if (fileName.endsWith("xlsx"))
{
workbook = new XSSFWorkbook();
} else if (fileName.endsWith("xls"))
{
workbook = new HSSFWorkbook();
} else
{
try
{
throw new Exception("invalid file name, should be xls or xlsx");
} catch (Exception e)
{
logger.info("必須是xls或者xlsx結尾的檔案.");
e.printStackTrace();
}
}
Sheet sheet = workbook.createSheet(title);
CellStyle style = workbook.createCellStyle();
// 列名
Row row = sheet.createRow(0);
switch (type) {
case "1":
for (int i = 0; i < headers.length; i++)
{
Cell cell = row.createCell(i);
sheet.setColumnWidth(i, 5000);
style.setAlignment(CellStyle.ALIGN_CENTER);
cell.setCellValue(headers[i]);
}
break;
case "2":
for (int i = 0; i < headersTitle.length; i++)
{
Cell cell = row.createCell(i);
sheet.setColumnWidth(i, 5000);
style.setAlignment(CellStyle.ALIGN_CENTER);
cell.setCellValue(headersTitle[i]);
}
break;
}
Iterator<Map> it = dataset.iterator();
int index = 0;
while (it.hasNext())
{
index++;
row = sheet.createRow(index);
Map map = it.next();
logger.info(map.toString());
Set<String> mapKey = (Set<String>)map.keySet();
logger.info(mapKey.toString());
Iterator<String> iterator = mapKey.iterator();
logger.info(iterator.toString());
int num = 0;
while(iterator.hasNext()){
Cell cell = row.createCell(num);
num++;
String key = iterator.next();
logger.info(key);
Object obj = map.get(key);
if (obj instanceof Date || obj instanceof Timestamp)
{
SimpleDateFormat sdf = new SimpleDateFormat(pattern);
cell.setCellValue(sdf.format(obj));
} else if (obj instanceof Integer)
{
cell.setCellValue((Integer) obj);
} else if (obj instanceof Double)
{
cell.setCellValue((Double) obj);
}else
{
cell.setCellValue((String) obj);
}
}
}
FileOutputStream fos;
try
{
fos = new FileOutputStream(fileName);
workbook.write(fos);
fos.close();
flag = true;
} catch (FileNotFoundException e)
{
logger.info("檔案不存在");
flag = false;
e.printStackTrace();
} catch (IOException e)
{
logger.info("檔案寫入錯誤");
flag = false;
e.printStackTrace();
}
return flag;
}
/**
* 實體類轉map
* @param obj
* @return
*/
public static Map<String, Object> transBean2Map(Object obj) {
if (obj == null) {
return null;
}
Map<String, Object> map = new HashMap<String, Object>();
try {
BeanInfo beanInfo = Introspector.getBeanInfo(obj.getClass());
PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors();
for (PropertyDescriptor property : propertyDescriptors) {
String key = property.getName();
// 過濾class屬性
if (!key.equals("class")) {
// 得到property對應的getter方法
Method getter = property.getReadMethod();
Object value = getter.invoke(obj);
map.put(key, value);
}
}
} catch (Exception e) {
logger.error("transBean2Map Error {}" ,e);
}
return map;
}
}
8.建立Test類（測試類）
package CzExcel;
import java.sql.Timestamp;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Map;
/**
* 測試類
* @author xgf
*
*/
public class Test {
public static void main(String[] args) {
//初始化資料
List<Model> list=new ArrayList<Model>();
for (int i = 0; i < 10; i++) {
Model model=new Model();
model.setMc("測試"+i);
model.setRq(new Date());
model.setSj(new Timestamp(System.currentTimeMillis()));
model.setType("111111111111111");
list.add(model);
}
String fileName="D:\\test\\text.xlsx";
//自定義excel表格表頭展示欄位順序
//獲取實體類欄位
Map<String,String> map = ClassUtil.getAllDesc(new Model());
Object[] keys = map.keySet().toArray();//從實體類中取欄位
String[] headers=new String[keys.length];
StringBuffer str=new StringBuffer("{");
for (int i = 0; i < keys.length; i++) {
headers[i]=keys[i].toString();
str.append("\""+keys[i].toString()+"\"");
if(i<(keys.length-1)){
str.append(",");
}
}
str.append("}");
System.out.println(str.toString());//把打印出來的字串拷貝到headers=後面，根據需要，調整欄位顯示的順序
//String[] headers={"type","mc","rq","sj"};
ExportExcel.exportExcelUtil(list,fileName,"1",headers,new Model());
}
}
例項程式碼（例項程式碼中支援多個工作空間資料的匯入）