图片上传工具类

前端上传页面

<form method="post" class="addFormSingle" action="admin_productImage_add" enctype="multipart/form-data">
    <table class="addTable">
        <tr>
            <td>请选择本地图片 尺寸400X400 为佳</td>
        </tr>
        <tr>
            <td>
                <input id="imageSingle" type="file" name="image" />
            </td>
        </tr>
        <tr class="submitTR">
            <td align="center">
                <input type="hidden" name="pid" value="${p.id}" />
                <button type="submit">提 交</button>
            </td>
        </tr>
    </table>
</form>

接收图片类（UploadedImageFile）

import org.springframework.web.multipart.MultipartFile;

public class UploadedImageFile {
    MultipartFile image;

    public MultipartFile getImage() {
        return image;
    }

    public void setImage(MultipartFile image) {
        this.image = image;
    }

}

图片格式工具类

import java.awt.Image;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.DataBuffer;
import java.awt.image.DataBufferInt;
import java.awt.image.DirectColorModel;
import java.awt.image.PixelGrabber;
import java.awt.image.Raster;
import java.awt.image.RenderedImage;
import java.awt.image.WritableRaster;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;

public class ImageUtil {
 
    //将图片转成jpg格式
    public static BufferedImage change2jpg(File f) {
        try {
            Image i = Toolkit.getDefaultToolkit().createImage(f.getAbsolutePath());
            PixelGrabber pg = new PixelGrabber(i, 0, 0, -1, -1, true);
            pg.grabPixels();
            int width = pg.getWidth(), height = pg.getHeight();
            final int[] RGB_MASKS = { 0xFF0000, 0xFF00, 0xFF };
            final ColorModel RGB_OPAQUE = new DirectColorModel(32, RGB_MASKS[0], RGB_MASKS[1], RGB_MASKS[2]);
            DataBuffer buffer = new DataBufferInt((int[]) pg.getPixels(), pg.getWidth() * pg.getHeight());
            WritableRaster raster = Raster.createPackedRaster(buffer, width, height, width, RGB_MASKS, null);
            BufferedImage img = new BufferedImage(RGB_OPAQUE, raster, false, null);
            return img;
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return null;
        }
    }
    //修改图片的尺寸并保存到指定文件夹
    public static void resizeImage(File srcFile, int width,int height, File destFile) {
        try {
            if(!destFile.getParentFile().exists())
                destFile.getParentFile().mkdirs();
            Image i = ImageIO.read(srcFile);
            i = resizeImage(i, width, height);
            ImageIO.write((RenderedImage) i, "jpg", destFile);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    //修改图片的尺寸
    public static Image resizeImage(Image srcImage, int width, int height) {
        try {

            BufferedImage buffImg = null;
            buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
            buffImg.getGraphics().drawImage(srcImage.getScaledInstance(width, height, Image.SCALE_SMOOTH), 0, 0, null);

            return buffImg;
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return null;
    }

}

上传图片Controller

import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;
import javax.servlet.http.HttpSession;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
@Controller
public class ImageController {
 @RequestMapping("admin_category_add")
    public String add(Integer imageId, HttpSession session, UploadedImageFile uploadedImageFile) throws IOException {
        File  imageFolder= new File(session.getServletContext().getRealPath("img/imgFile"));
        File file = new File(imageFolder,imageId+".jpg");
        if(!imageFolder.exists())
            imageFolder.mkdirs();
            //保存图片到file对象中
        uploadedImageFile.getImage().transferTo(file);
        //将图片转成jpg格式
        BufferedImage img = ImageUtil.change2jpg(file);
        //将图片写入文件所在位置
        ImageIO.write(img, "jpg", file);
        return "redirect:/admin_category_list";
    }
}