spring的一个用于读取文件系统下的资源的一个实现类，使用起来非常简单。
FileSystemResource部分源码获取文件的输入流
@Override
public InputStream getInputStream() throws IOException {
try {
return Files.newInputStream(this.filePath);
}
catch (NoSuchFileException ex) {
throw new FileNotFoundException(ex.getMessage());
}
}
判断资源是否可写(如果是目录那就肯定不可写啦)
@Override
public boolean isWritable() {
return (this.file != null ? this.file.canWrite() && !this.file.isDirectory() :
Files.isWritable(this.filePath) && !Files.isDirectory(this.filePath));
}
FileSystemResource使用例子
读取一个文件，写（覆盖）些数据进去
@Test
public void testFileSystemResourc() throws IOException {
String path = "F://test.txt";
FileSystemResource fileSystemResource = new FileSystemResource(path);
System.out.println(fileSystemResource.isFile());
System.out.println("长度:"+fileSystemResource.contentLength());
System.out.println("文件名"+fileSystemResource.getFilename());
//FileSystemResource实现了WritableResource接口
OutputStream outputStream = fileSystemResource.getOutputStream();
OutputStreamWriter outputStreamWriter = new OutputStreamWriter(outputStream);
outputStreamWriter.write("123456789");
outputStreamWriter.flush();
outputStreamWriter.close();
}
