创建实体Java Bean--Student
public class Student {
private int id;
private String name;
private int age;
private Date birth;
public Student() { }
public Student(int id, String name, int age, Date birth) {
super();
this.id = id;
this.name = name;
this.age = age;
this.birth = birth;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public Date getBirth() {
return birth;
}
public void setBirth(Date birth) {
this.birth = birth;
}
}
- 创建Excel表
public class CreateXLS {
private static String path = "E:/Student.xls";
private static List<Student> mList;
/**工作簿*/
private static HSSFWorkbook workbook;
static {
mList = new ArrayList<Student>();
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-mm-dd");
try {
Student user1 = new Student(1, "张三", 16,
dateFormat.parse("1997-03-12"));
Student user2 = new Student(2, "李四", 17,
dateFormat.parse("1996-08-12"));
Student user3 = new Student(3, "王五", 26,
dateFormat.parse("1985-11-12"));
mList.add(user1);
mList.add(user2);
mList.add(user3);
} catch (ParseException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
workbook = new HSSFWorkbook();
// 第二步， 在webbook中添加一个sheet，对应Excel文件中的sheet
HSSFSheet sheet = workbook.createSheet("学生表一");
// 第三步，在sheet中添加表头第0行，注意老版本poi对Excel的行数列数有限制short
HSSFRow row = sheet.createRow(0);
// 第四步，创建单元格，并设置值表头，设置表头居中
HSSFCellStyle style = workbook.createCellStyle();
style.setAlignment(HorizontalAlignment.CENTER);// 创建一个居中格式
// 创建第一行
HSSFCell cell = row.createCell(0);
cell.setCellValue("学号");
cell.setCellStyle(style);
cell = row.createCell(1);
cell.setCellValue("姓名");
cell.setCellStyle(style);
cell = row.createCell(2);
cell.setCellValue("年龄");
cell.setCellStyle(style);
cell = row.createCell(3);
cell.setCellValue("生日");
cell.setCellStyle(style);
// 第五步，写入实体数据 实际应用中这些数据从数据库得到，
for (int i = 0; i < mList.size(); i++) {
row = sheet.createRow(i + 1);
Student student = mList.get(i);
// 第四步，创建单元格，并设置值
row.createCell((short) 0).setCellValue((double) student.getId());
row.createCell((short) 1).setCellValue(student.getName());
row.createCell((short) 2).setCellValue((double) student.getAge());
cell = row.createCell((short) 3);
cell.setCellValue(new SimpleDateFormat("yyyy-mm-dd").format(student.getBirth()));
}
try{
FileOutputStream fout = new FileOutputStream(path);
workbook.write(fout);
fout.close();
} catch (Exception e){
e.printStackTrace();
}
}
}
- 读取Excel表
public class ReadXLS {
private static String path = "E:/Student.xls";
public static void main(String[] args) throws IOException {
List<List<Map<String,String>>> list = readExcelWithTitle(path);
System.out.println(list.toString());
}
/**
* [[{姓名=张三, 生日=1997-03-12, 学号=1.0, 年龄=16.0},
* {姓名=李四, 生日=1996-08-12, 学号=2.0, 年龄=17.0},
* {姓名=王五, 生日=1985-11-12, 学号=3.0, 年龄=26.0}]]
*/
public static List<List<Map<String, String>>> readExcelWithTitle(String path) throws IOException {
String fileType = path.substring(path.lastIndexOf(".")+1, path.length());
InputStream inputStream = null;
Workbook workbook = null;
try {
inputStream = new FileInputStream(path);
if (fileType.equals("xls")){
workbook = new HSSFWorkbook(inputStream);
}
// 对应excel文件
List<List<Map<String, String>>> result = new ArrayList<List<Map<String,String>>>();
// 遍历sheet页
int sheetSize = workbook.getNumberOfSheets();
for (int i = 0; i < sheetSize; i++) {
Sheet sheet = workbook.getSheetAt(i);
// 对应sheet页
List<Map<String, String>> sheetList = new ArrayList<Map<String,String>>();
// 对应所有标题
List<String> titles = new ArrayList<String>();
// 遍历行
int rowSize = sheet.getLastRowNum() + 1;
for (int j = 0; j < rowSize; j++) {
Row row = sheet.getRow(j);
if (null == row) { // 略过空行
continue;
}
int cellSize = row.getLastCellNum();// 行中有多少个单元格，也就是有多少列
if (0 == j) {
for (int k = 0; k < cellSize; k++) {
Cell cell = row.getCell(k);
titles.add(cell.toString());
}
} else { // 其他数据行
Map<String, String> rowMap = new HashMap<String, String>();
for (int k = 0; k < cellSize; k++) {
Cell cell = row.getCell(k);
String key = titles.get(k);
String value = null;
if (null != cell) {
value = cell.toString();
}
rowMap.put(key, value);
}
sheetList.add(rowMap);
}
}
result.add(sheetList);
}
return result;
} catch (Exception e) {
e.printStackTrace();
} finally {
if (null != workbook) {
workbook.close();
}
if (null != inputStream) {
inputStream.close();
}
}
return null;
}
}
