Spring MVC上傳圖片,Java二進位制圖片寫入資料庫,生成略縮圖
阿新 • • 發佈:2018-12-14
步驟:1.將圖片上傳到伺服器的一個磁碟目錄下。 2.將剛才上傳好的圖片寫入資料庫image欄位。
一、上傳圖片:使用的是spring mvc 對上傳的支援。
jsp 頁面:
<form name="uploadForm" id="uploadForm" method="post" action="${base}goods/doUploadFile" enctype="multipart/form-data"> <input type="file" name="image" /><br/> <input type="submit" value="上傳" class="btn4" /> </form>
spring_mvc.xml配置
<bean
id="multipartResolver"
class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
</bean>
Controller:
@RequestMapping("/doUploadFile") public ModelAndView doUploadFile(HttpServletRequest request, HttpServletResponse response, HttpSession session) throws Exception, IOException { // 轉型為MultipartHttpRequest: MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request; // 獲得檔案: MultipartFile file = multipartRequest.getFile("image"); // 獲得檔名: String filename = file.getOriginalFilename(); InputStream input = file.getInputStream(); // String path = "D:/goodsImages";下邊這個path是寫在配置檔案裡邊的,方便修改,這個方法很長但或得的結果就是路勁D:/goodsImages String path = ConfigConstants.getInstance() .get("goods.uploadImage.dir"); File savePath = new File(path); if (!savePath.exists()) { // 資料夾 savePath.mkdir(); } SaveFileFromInputStream(input, savePath.toString(), filename); String result = "上傳成功!"; ModelAndView modelAndView = new ModelAndView("goods/uploadSuccess"); modelAndView.addObject("result", result); modelAndView.addObject("filename", filename); return modelAndView; }
如此上傳就搞定了。
上傳檔案補充,另一個方法:
1.專案中匯入 jar 包 cos.jar
2.表單: enctype=“multipart/form-data”
3.處理方法:主要用到 MultipartRequest 類 ,詳細情況檢視:
@RequestMapping(value = "/uploadImage.do") public String uploadImage(HttpServletRequest request) throws Exception { MultipartRequest mr = null; int maxPostSize = 1 * 100 * 1024; mr=new MultipartRequest(request,"E:\\goodsImages",maxPostSize,"GBK"); return null; }
二、生成略縮圖。
public void createIcon() {
try {
File fiBig = new File("D:/log/tickit.png"); // 大圖檔案
File foSmall = new File("D:/log/tickitIcon.png"); // 將要轉換出的小圖檔案
AffineTransform transform = new AffineTransform();
//讀取圖片
BufferedImage bis = ImageIO.read(fiBig);
//獲得圖片原來的高寬
int w = bis.getWidth();
int h = bis.getHeight();
double scale = (double) w / h;//等比例縮放
int nowWidth = 120;
int nowHeight = (nowWidth * h) / w;
if (nowHeight > 120) {
nowHeight = 120;
nowWidth = (nowHeight * w) / h;
}
double sx = (double) nowWidth / w;
double sy = (double) nowHeight / h;
transform.setToScale(sx, sy);
AffineTransformOp ato = new AffineTransformOp(transform, null);
BufferedImage bid = new BufferedImage(nowWidth, nowHeight,
BufferedImage.TYPE_3BYTE_BGR);
ato.filter(bis, bid);
ImageIO.write(bid, "png", foSmall);
} catch (Exception e) {
e.printStackTrace();
}
}
三、圖片寫入資料庫。 1.圖片實體類的 圖片欄位(picture) 用 byte[]型別
@Entity
@Table(name = "spaq_pic")
public class GoodsPic {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "pic_id")
private Long picId;
@Column(name = "pic_name")
private String picName;
@Column(name = "pic_descr")
private String picDescr;
@Column(name = "picture")
private byte[] picture;//
//省略其他欄位及get,set方法
}
2.程式碼,讀取本地圖片儲存在byte[]中,付給實體類的picture欄位,呼叫 hibernate的save方法儲存
/**
* hibernate儲存圖片到資料表
*/
@Transactional(readOnly = false)
public void hibsaveImage(GoodsPic gp, String path) {//GoodsPic為圖片實體類,path為圖片所在磁碟的路徑
try {
InputStream in = null;
in = new FileInputStream(path);
byte[] b = new byte[in.available()];
in.read(b);
in.close();
gp.setPicture(b);
myDao.save(gp);
} catch (Exception e) {
e.printStackTrace();
}
}