springboot 在ftp上获取pdf文件存到内存传到前端
时间: 2024-10-18 21:18:27 浏览: 5
Spring Boot是一个轻量级的Java全栈框架,它简化了初始项目设置以及开发过程。要在Spring Boot应用中处理FTP上传和PDF文件传输给前端,你可以按照以下步骤操作:
1. 添加依赖:首先,在你的`pom.xml`中添加FTP客户端库和PDF处理库的依赖,例如Apache Commons VFS for FTP和Apache PDFBox。
```xml
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>commons-vfs</groupId>
<artifactId>commons-vfs2</artifactId>
</dependency>
<dependency>
<groupId>org.apache.pdfbox</groupId>
<artifactId>pdfbox</artifactId>
</dependency>
</dependencies>
```
2. FTP连接配置:创建一个配置类,比如`FtpConfig`,并提供FTP服务器的连接信息,如用户名、密码、URL等。
```java
@Configuration
public class FtpConfig {
private static final String FTP_URL = "ftp://username:password@hostname";
@Value("${spring.freemarker.cache:false}")
private boolean ftpCache;
@Bean
public FileSystemManager fsm() throws Exception {
SimpleConfiguration config = new SimpleConfiguration();
config.setURL(FTP_URL);
return newFileSystemManager(config);
}
}
```
3. 服务层处理:创建一个Service类,使用`FileSystemManager`从FTP下载PDF文件,并将其转换为字节流。
```java
@Service
public class PdfService {
private final FileSystemManager fsm;
public PdfService(FtpConfig ftpConfig) {
this.fsm = ftpConfig_fsm;
}
public byte[] downloadAndConvertPdf(String filePath) {
try (InputStream in = fsm.getResourceAsStream(filePath)) {
// 使用PDFBox读取PDF内容
PDDocument document = PDDocument.load(in);
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
try {
document.save(outputStream);
return outputStream.toByteArray();
} finally {
document.close();
}
} catch (IOException e) {
throw new RuntimeException("Failed to read PDF from FTP", e);
}
}
}
```
4. 控制层API:在Controller中,接收前端请求,调用`PdfService`下载PDF并返回给前端。
```java
@RestController
@RequestMapping("/api/pdf")
public class PdfController {
private final PdfService pdfService;
public PdfController(PdfService pdfService) {
this.pdfService = pdfService;
}
@GetMapping("/{filePath}")
public ResponseEntity<byte[]> getPdfFromFtp(@PathVariable String filePath) {
try {
byte[] bytes = pdfService.downloadAndConvertPdf(filePath);
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
return ResponseEntity.ok().headers(headers).body(bytes);
} catch (Exception e) {
return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(null);
}
}
}
```
5. 前端接收:在前端使用AJAX或者Fetch API从/api/pdf路径发送GET请求,接收响应并显示PDF内容。
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