java生成图片缩略图方法

在一些详情页面中，可能需要对上传到服务器中的图片生成以缩略图的形式展示，下面就是一个生成缩略图的例子，采用的java web开发：

 

                <tr>
                    <td class="detailTitle">示例图片</td>
                    <td colspan="3">
                        #if("$!{riskRelation4picUpload.summary}"!="")
                        <div class="d103">
                            <a href="/getSamplePicture.action?riskId=$!{catalog.code}" target="_blank"
                               title="点击图片查看大图>>">
                                <img class="pictrue111"
                                     src="/getSamplePicture.action?riskId=$!{catalog.code}"></img>
                            </a>
                        </div>
                        <div style="clear:both;"></div>
                        <div class="d102">图片名称：$!{riskRelation4picUpload.summary}</div>
                        #end
                    </td>
                </tr>

 

java文件：

 

	@RequestMapping("/getSamplePicture.action")
	public ModelAndView doGetSamplePicture(HttpServletRequest request,
			HttpServletResponse response) {
		ModelAndView mav = new ModelAndView("ajaxText");
		String riskId = request.getParameter("riskId");
		RiskRelation riskRelation = riskRelationDao.getOne(riskId,
				Constants4BizType.UPLOAD_PIC_BUNINESS_TPYE);
		byte[] samplePic = riskRelation.getAttachment();
		String fileName = riskRelation.getSummary();
		String fileType = "";
		if (!StringUtil.isNullOrEmpty(fileName)) {
			fileType = fileName.substring(fileName.lastIndexOf("."));
		}
		response.reset();
		if ((".jpg").equals(fileType) || ("jpeg").equals(fileType)) {
			response.setContentType("image/jpeg;charset=GB2312");
		} else if (".gif".equals(fileType)) {
			response.setContentType("image/gif;charset=GB2312");
		} else if (".png".equals(fileType)) {
			// application/x-png
			response.setContentType("image/png");
		} else if (".bmp".equals(fileType)) {
			response.setContentType("application/x-bmp");
		}

		try {
			OutputStream out = response.getOutputStream();
			out.write(samplePic);
			out.flush();
			out.close();
		} catch (Exception e) {
			e.printStackTrace();
		}

		return mav;
	}