Question

我正在学习使用 Spring Boot 和 angular 从数据库中保存和检索图像的教程。我试图用 Postman 对其进行测试，将图像放入数据库中，但出现 404 错误。下面是邮递员的图片任何人都可以向我解释这是什么原因吗？谢谢大家

ImageModel.java

package com.javainuse.model;
import javax.persistence.*;
@Entity
@Table(name = "image_table")
public class ImageModel {
    public ImageModel() {
        super();
    }
    public ImageModel(String name, String type, byte[] picByte) {
        this.name = name;
        this.type = type;
        this.picByte = picByte;
    }
    @Id
    @Column(name = "id")
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    @Column(name = "name")
    private String name;
    @Column(name = "type")
    private String type;
    //image bytes can have large lengths so we specify a value
    //which is more than the default length for picByte column
    @Column(name = "picByte", length = 1000)
    private byte[] picByte;
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getType() {
        return type;
    }
    public void setType(String type) {
        this.type = type;
    }
    public byte[] getPicByte() {
        return picByte;
    }
    public void setPicByte(byte[] picByte) {
        this.picByte = picByte;
    }
}

ImageRepository.java

package com.javainuse.db;
import java.util.Optional;
import org.springframework.data.jpa.repository.JpaRepository;
import com.javainuse.model.ImageModel;
public interface ImageRepository extends JpaRepository<ImageModel, Long> {
    Optional<ImageModel> findByName(String name);
}

图片上传控制器

package com.javainuse.controller;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Optional;
import java.util.zip.DataFormatException;
import java.util.zip.Deflater;
import java.util.zip.Inflater;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.http.ResponseEntity.BodyBuilder;
import org.springframework.web.bind.annotation.CrossOrigin;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;
import com.javainuse.db.ImageRepository;
import com.javainuse.model.ImageModel;
@RestController
@CrossOrigin(origins = "http://localhost:4200")
@RequestMapping(path = "image")
public class ImageUploadController {
    @Autowired
    ImageRepository imageRepository;
    @PostMapping("/upload")
    public BodyBuilder uplaodImage(@RequestParam("imageFile") MultipartFile file) throws IOException {
        System.out.println("Original Image Byte Size - " + file.getBytes().length);
        ImageModel img = new ImageModel(file.getOriginalFilename(), file.getContentType(),
                compressBytes(file.getBytes()));
        imageRepository.save(img);
        return ResponseEntity.status(HttpStatus.OK);
    }
    @GetMapping(path = { "/get/{imageName}" })
    public ImageModel getImage(@PathVariable("imageName") String imageName) throws IOException {
        final Optional<ImageModel> retrievedImage = imageRepository.findByName(imageName);
        ImageModel img = new ImageModel(retrievedImage.get().getName(), retrievedImage.get().getType(),
                decompressBytes(retrievedImage.get().getPicByte()));
        return img;
    }
    // compress the image bytes before storing it in the database
    public static byte[] compressBytes(byte[] data) {
        Deflater deflater = new Deflater();
        deflater.setInput(data);
        deflater.finish();
        ByteArrayOutputStream outputStream = new ByteArrayOutputStream(data.length);
        byte[] buffer = new byte[1024];
        while (!deflater.finished()) {
            int count = deflater.deflate(buffer);
            outputStream.write(buffer, 0, count);
        }
        try {
            outputStream.close();
        } catch (IOException e) {
        }
        System.out.println("Compressed Image Byte Size - " + outputStream.toByteArray().length);
        return outputStream.toByteArray();
    }
    // uncompress the image bytes before returning it to the angular application
    public static byte[] decompressBytes(byte[] data) {
        Inflater inflater = new Inflater();
        inflater.setInput(data);
        ByteArrayOutputStream outputStream = new ByteArrayOutputStream(data.length);
        byte[] buffer = new byte[1024];
        try {
            while (!inflater.finished()) {
                int count = inflater.inflate(buffer);
                outputStream.write(buffer, 0, count);
            }
            outputStream.close();
        } catch (IOException ioe) {
        } catch (DataFormatException e) {
        }
        return outputStream.toByteArray();
    }
}

邮递员错误 postman error

Answer 1

您好 elfuso 请添加路径斜线示例

  @RequestMapping(path = "/image")

尝试测试 springboot 代码时 Postman 出现 404 错误

1 个答案: