我正在使用public void onClick(View v) {
// WallpaperManager myWallpaperManager = WallpaperManager.getInstance(getApplicationContext());
InputStream is = getResources().openRawResource(R.raw.gradient);
Bitmap b = BitmapFactory.decodeStream(is);
try {
// myWallpaperManager.setBitmap(+ R.drawable.gradient);
getApplicationContext().setWallpaper(b);
Toast.makeText(getApplicationContext(),"Wallpaper updated", Toast.LENGTH_SHORT ).show();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
来读取Spring Batch Excel Extension文件。我克隆了源代码并做了Excel (.xlx)并将依赖项添加到了Spring Boot项目中。我还添加了mvn install。
我的Excel文件包含简单的数据：
Apache poi-ooxml这是我的Id Last Name First Name
3 Aguinaldo Emilio
4 Aquino Melchora
5 Dagohoy Francisco
6 Luna Antonio
7 Jacinto Emilio
班：
Student我创建了实用程序类，其方法可以实际读取Excel文件：
@Entity
public class Student {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private long id;
@NotBlank(message = "{NotBlank.student.lastName}")
private String lastName;
@NotBlank(message = "{NotBlank.student.firstName}")
private String firstName;
private LocalDateTime createdAt;
// getters, setters
}
上传文件后，我将选择一个文件以将其数据导入我的数据库：
public class ExcelUtils {
public static <T> ItemReader<T> excelToItemReader(Path file, Class<T> clazz) throws Exception {
PoiItemReader<T> reader = new PoiItemReader<>();
reader.setLinesToSkip(1);
System.out.println("File Name: " + file.toString()); // Displays: File Name: uploads\excel\<Excel file selected to import>
Resource resource = new FileSystemResource(file);
System.out.println("File exists? " + resource.exists()); // Displays: File exists? true
reader.setResource(resource);
reader.setRowMapper(excelRowMapper(clazz));
return reader;
}
private static <T> RowMapper<T> excelRowMapper(Class<T> clazz) {
BeanWrapperRowMapper<T> rowMapper = new BeanWrapperRowMapper<>();
rowMapper.setTargetType(clazz);
return rowMapper;
}
}
我不明白为什么在控制台中完全没有错误登录时@PostMapping("/import")
public String importStudents(@RequestParam String fileName, RedirectAttributes redirectAttributes) throws Exception {
ItemReader<Student> studentItemReader = ExcelUtils.excelToItemReader(storageService.load(fileName), Student.class);
Student student = studentItemReader.read();
if (student != null) {
System.out.println("Student has data.");
studentService.save(student);
} else {
System.out.println("Student is null");
throw new Exception("Student is null");
}
redirectAttributes.addFlashAttribute("message", "You successfully imported students data from " + fileName + "!");
return "redirect:/students";
}
会得到student。