图片上传工具类

package com.util;

 

import java.awt.Image;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import java.util.ArrayList;

import java.util.Date;

import java.util.List;

 

import javax.imageio.ImageIO;

import javax.servlet.http.HttpServletRequest;

 

import org.springframework.web.multipart.MultipartFile;

import org.springframework.web.multipart.MultipartHttpServletRequest;

import com.sun.image.codec.jpeg.JPEGCodec;

import com.sun.image.codec.jpeg.JPEGImageEncoder;

 

/*******************************************************************************

 * 缩略图类（通用） 本java类能将jpg、bmp、png、gif图片文件，进行等比或非等比的大小转换。 具体使用方法

 * compressPic(大图片路径,生成小图片路径,大图片文件名,生成小图片文名,生成小图片宽度,生成小图片高度,是否等比缩放(默认为true))

 */

public class CompressPic {

    public String addImages(HttpServletRequest request,String Urlpath,String InputfileName) {

        String realFileName = "";

        // 转型为MultipartHttpRequest(重点的所在)

        MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request;

        // 获得第1张图片（根据前台的name名称得到上传的文件）

        MultipartFile imgFile1 = multipartRequest.getFile(InputfileName);

        // 定义一个数组，用于保存可上传的文件类型

        List<String> fileTypes = new ArrayList<String>();

        fileTypes.add("jpg");

        fileTypes.add("jpeg");

        fileTypes.add("bmp");

        fileTypes.add("png");

        if (!(imgFile1.getOriginalFilename() == null || "".equals(imgFile1.getOriginalFilename()))) {

            String fileName = imgFile1.getOriginalFilename();

            // 获取上传文件类型的扩展名,先得到.的位置，再截取从.的下一个位置到文件的最后，最后得到扩展名

            String ext = fileName.substring(fileName.lastIndexOf(".") + 1,fileName.length());

            // 对扩展名进行小写转换

            ext = ext.toLowerCase();

            if (fileTypes.contains(ext)) {// 如果扩展名属于允许上传的类型，则创建文件

                try {

                    realFileName = String.valueOf(new Date().getTime()) + "."+ ext;

                    String path = request.getSession().getServletContext().getRealPath("/");

                    File f = new File(path + Urlpath + realFileName);

                    System.out.println("filePath="+path + Urlpath + realFileName);

                    imgFile1.transferTo(f);

                    Image img = ImageIO.read(f);

                    // 判断图片格式是否正确

                    if (img.getWidth(null) == -1)

                        return "no";

                    else {

                        BufferedImage tag = new BufferedImage(129, 100,BufferedImage.TYPE_INT_RGB);

                        tag.getGraphics().drawImage(img.getScaledInstance(129, 100,Image.SCALE_SMOOTH), 0, 0, null);

                        FileOutputStream out = new FileOutputStream(path + Urlpath + realFileName);

//                      FileOutputStream out2 = new FileOutputStream("D:\\WorkSpace\\onlinefdc\\WebRoot\\"+Urlpath+realFileName);

                        // JPEGImageEncoder可适用于其他图片类型的转换

                        JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);

//                      JPEGImageEncoder encoder2 = JPEGCodec.createJPEGEncoder(out2);

                        encoder.encode(tag);

//                      encoder2.encode(tag);

                        out.close();

//                      out2.close();

                    }

//                  f.delete();

                    System.out.println("f.exists="+f.exists());

                } catch (Exception e) {

                    e.printStackTrace();

                }

            }

        }

        return realFileName;

    }

}