| * 标题： | |
| 封面图片： | 尺寸：520*320 px 文件大小：100KB以内，文件格式：jpg,jpeg,gif,bmp,png |
| * 内容： |
java项目实例图片上传
使用 Spring中MultipartHttpServletRequest实现文件上传
一、上传对表单的要求
1) 表单的提交方式 ："method=post"
2) 表单的类型 ：enctype="multipart/form-data"
3) 上传表单的文件项：
二.上传的一般步骤
1.将request转化为MultipartHttpServletRequest multipartRequest= (MultipartHttpServletRequest)(request);
原理是：使用spring的CommosMultipartResolver 配置MultipartResolver 用于文件上传，DispatcherServlet 将调用 MultipartResolver 的 isMultipart(request) 方法检查当前 Web 请求是否为 multipart类型。如果是，DispatcherServlet 将调用 MultipartResolver 的 resolveMultipart(request) 方法，对原始 request 进行装饰，并返回一个 MultipartHttpServletRequest 供后继处理流程使用(最初的 HttpServletRequest 被偷梁换柱成了 MultipartHttpServletRequest)，否则，直接返回最初的 HttpServletRequest。
获取文件
MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request; //将request转化为MultipartHttpServletRequest
MultipartFile multipartFile = multipartRequest.getFile("upload");//获取文件
InputStream is = multipartFile.getInputStream();//获取图片的文件流
String uploadContentType = multipartFile.getOriginalFilename();//获取文件的格式
3.对图片进行处理（压缩图片），并输出到指定目录
4.在数据库中保存图片的路径名imgDir+imgName
jsp页面代码
<%@ page language="java" pageEncoding="UTF-8"%>
<%@include file="/include.jsp"%>
<%@page import="java.util.Date"%>
<%-- 1 图文新闻 --%>
java 后台代码
controller
@Autowired
private Executor threadPoolTaskExecutor;
/**
*后台添加电子院报章节内容
*
*
*/
@RequestMapping(value = "/m/periodicals/addContentDo")
public void addContentDo(@ModelAttribute PeriodicalsChapter periodicalsChapter,Model model,HttpServletRequest request,HttpServletResponse response){
Map map = new HashMap();
InputStream is = null;
Gson gson = new Gson();
try{
MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request;
MultipartFile multipartFile = multipartRequest.getFile("upload");
String uploadContentType = multipartFile.getOriginalFilename();
if(multipartFile != null && multipartFile.getSize() != 0){
String expandedName = CommonUtil.checkImg(uploadContentType);
if(expandedName.equals("")){
map.put("resultCode", 3);
map.put("resultMsg", "文件格式不正确（必须为.jpg/.gif/.bmp/.png文件）!");
String jsonStr = gson.toJson(map);
AjaxUtil.ajaxHtml(jsonStr, response);
return ;
}
String imgName = System.currentTimeMillis() + "_" + ((int) (Math.random() * 900) + 100) + "." + expandedName;
is = multipartFile.getInputStream();
threadPoolTaskExecutor.execute(
new ImageCompressionTask(is, imgName, 520, 320)
);
periodicalsChapter.setTopThumbUrl(CommonUtil.getFolder(imgName));
}//压缩图片
periodicalsChapter.setCreateTime(new Date().getTime());//获取时间
periodicalsChapter.setTitle(periodicalsChapter.getTitle());
periodicalsChapter.setContent(periodicalsChapter.getContent());
periodicalsChapter.setParentId(periodicalsChapter.getParentId());
//保存
if(periodicalsChapterService.addPeriodicalsChapter(periodicalsChapter)){
map.put("resultCode", 0);
map.put("resultMsg", "发布成功");
String jsonStr = gson.toJson(map);
AjaxUtil.ajaxHtml(jsonStr, response);
return ;
}else{
map.put("resultCode", 1);
map.put("resultMsg", "发布失败");
String jsonStr = gson.toJson(map);
AjaxUtil.ajaxHtml(jsonStr, response);
}
}catch(Exception e){
logger.error("保存异常",e);
map.put("resultCode", 1);
map.put("resultMsg", "发布失败");
String jsonStr = gson.toJson(map);
AjaxUtil.ajaxHtml(jsonStr, response);
}
}
1.
CommonUti类的
checkImg的方法,检查文件的格式
package com.rmyy.web.common;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import javax.imageio.ImageIO;
import org.apache.commons.fileupload.disk.DiskFileItem;
import org.springframework.ui.ModelMap;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.commons.CommonsMultipartFile;
import com.rmyy.web.model.Channel;
import com.rmyy.web.util.DateUtil;
import com.rmyy.web.util.PropertyFileUtil;
public class CommonUtil {
public static String getFolder(String imgName) {
// 图片上下文
String imgContext = PropertyFileUtil.get("imgContext");
String dateStr = DateUtil.getDate();
String imgDir = imgContext + "/" + dateStr + "/";
return imgDir+imgName;
}
public static String checkImg(String uploadContentType){
String expandedName = "";
if (uploadContentType.endsWith(".jpg") || uploadContentType.endsWith(".JPG")) {
// IE6上传jpg图片的headimageContentType是image/pjpeg，而IE9以及火狐上传的jpg图片是image/jpeg
expandedName = "jpg";
} else if (uploadContentType.endsWith(".png") || uploadContentType.endsWith(".PNG")) {
// IE6上传的png图片的headimageContentType是"image/x-png"
expandedName = "png";
} else if (uploadContentType.endsWith(".gif")) {
expandedName = "gif";
} else if (uploadContentType.endsWith(".bmp")) {
expandedName = "bmp";
}
return expandedName;
}
// 校验文件尺寸跟大小
public static String checkFileImg(MultipartFile file,String photoSizeStr,String photoWidthStr,String photoHeightStr) throws IOException {
int photoSize = photoSizeStr!=null?Integer.parseInt(photoSizeStr):0;
int photoWidth = photoWidthStr!=null?Integer.parseInt(photoWidthStr):0;
int photoHeight = photoHeightStr!=null?Integer.parseInt(photoHeightStr):0;
CommonsMultipartFile cf= (CommonsMultipartFile)file;
String result = "";
String tip = "请上传图片尺寸为"+photoWidth+"*"+photoHeight+"！";
BufferedImage image =ImageIO.read(cf.getInputStream());
//BufferedImage image = ImageIO.read(f);
if (file.getSize() > photoSize * 1024) {
result = "文件大小不得大于" + photoSize + "kb!";
return result;
}
if (image.getWidth() < (photoWidth) || image.getWidth() > (photoWidth + 20)) {
return tip;
}
if (image.getHeight() < (photoHeight) || image.getHeight() > (photoHeight + 20)) {
return tip;
}
return null;
}
}
package com.rmyy.web.common.task;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import javax.imageio.ImageIO;
import org.apache.log4j.Logger;
import com.rmyy.web.common.CommonUtil;
import com.rmyy.web.util.DateUtil;
import com.rmyy.web.util.ImageUtils;
import com.rmyy.web.util.PropertyFileUtil;
public class ImageCompressionTask implements Runnable{
protected static Logger logger = Logger.getLogger(ImageCompressionTask.class);
private InputStream is;
private int width;
private int height;
private String fileName;
/**
* 初始化参数
* @param file 图片
* @param id ID
* @param type 图片分类1为商家管理图片2为产品分类图片
* @param fileName 图片名称
* @param width 高
* @param height 宽
*/
public ImageCompressionTask(InputStream is,String fileName,int width,int height){
this.is = is;
this.width = width;
this.height = height;
this.fileName = fileName;
}
public void run() {
try{
this.compressPic();
}catch(Exception e){
logger.error("生成压缩图失败! " ,e);
}
}
/**
* 图片压缩
* @return
*/
private String compressPic() throws Exception {
String rootPath = PropertyFileUtil.get("imgPath");
String path = getFolder(rootPath); //根路径下的子目录
String urlPath = path + fileName;
BufferedImage buffImg;
FileOutputStream output = null;
try {
String extentionName = "";
if(fileName.lastIndexOf(".") != -1){
extentionName = fileName.substring(fileName.lastIndexOf(".") + 1).toLowerCase();
}
extentionName = extentionName.toLowerCase(); //没有扩展名的url
buffImg = ImageIO.read(is);
if(buffImg == null){
return null;
}
BufferedImage compressPic = ImageUtils.compressPicMin(buffImg, width, height);//图片等比缩放
if(compressPic != null){ //图片已压缩
output = new FileOutputStream(urlPath);
ImageUtils.write(compressPic, extentionName, output);//图片输出
}
}finally {
if(output != null){
try {
output.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if(is != null){
is.close();
}
}
return "";
}
//保存路径获取
private String getFolder(String rootPath) {
// 图片上下文
String imgContext = PropertyFileUtil.get("imgContext");
String dateStr = DateUtil.getDate();
String imgDir = imgContext + "/" + dateStr + "/";
String path = rootPath + imgDir;
File dir = new File(path);
if (!dir.exists()) {
try {
dir.mkdirs();
} catch (Exception e) {
return "";
}
}
return path;
}
public int getWidth() {
return width;
}
public void setWidth(int width) {
this.width = width;
}
public int getHeight() {
return height;
}
public void setHeight(int height) {
this.height = height;
}
public static Logger getLogger() {
return logger;
}
public static void setLogger(Logger logger) {
ImageCompressionTask.logger = logger;
}
public static void main(String args[]){
String abc = "abc";
String ab2 = "abc";
System.out.print(abc==ab2);
}
}
3.图片等比缩放,先要设置宽和高
package com.rmyy.web.util;
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import javax.imageio.ImageIO;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.methods.GetMethod;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Description: 图片工具类
*
* @author KangWei
* @Date 11-2-23
*/
public class ImageUtils {
private static final Logger log = LoggerFactory.getLogger(ImageUtils.class);
/**1111
* 将图片写入输出流
*
* @param image
* BufferedImage 对象
* @param format
* 输出格式
* @param output
* 输出流
* @throws java.io.IOException
* IO异常
*/
public static void write(BufferedImage image, String format,
OutputStream output) throws IOException {
ImageIO.write(image, format, output);
}
/**111
* 图片等比缩放,先要设置宽和高
*
* @param image
* @param
* @throws java.io.IOException
*/
public static BufferedImage compressPicMin(BufferedImage image,
int outputWidth, int outputHeight) throws IOException {
if (image == null) {
return null;
}
if (image.getWidth(null) < outputWidth
&& image.getHeight(null) < outputHeight) {
return image;
}
int newWidth;
int newHeight;
// 为等比缩放计算输出的图片宽度及高度
double rate1 = ((double) image.getWidth(null)) / (double) outputWidth;
double rate2 = ((double) image.getHeight(null)) / (double) outputHeight;
// 根据缩放比率大的进行缩放控制
double rate = rate1 < rate2 ? rate1 : rate2;
newWidth = (int) (((double) image.getWidth(null)) / rate);
newHeight = (int) (((double) image.getHeight(null)) / rate);
BufferedImage tag = new BufferedImage(newWidth, newHeight,
BufferedImage.TYPE_INT_RGB);
/*
* Image.SCALE_SMOOTH 的缩略算法 生成缩略图片的平滑度的 优先级比速度高 生成的图片质量比较好 但速度慢
*/
tag.getGraphics().drawImage(
image.getScaledInstance(newWidth, newHeight,
Image.SCALE_SMOOTH), 0, 0, null);
return tag;
}
}
4.系统性工具类
package com.rmyy.web.util;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
import org.apache.log4j.Logger;
/**
* 系统属性工具类
*
* @author HenryYan
*/
public class PropertyFileUtil {
private static Properties config = null;
private static Logger logger = Logger.getLogger(PropertyFileUtil.class);
static {
InputStream in = PropertyFileUtil.class.getClassLoader().getResourceAsStream("application.properties");
config = new Properties();
try {
config.load(in);
in.close();
} catch (IOException e) {
logger.error("加载系统参数配置异常========", e);
}
}
/**
* 根据key 得到value
* @param key
* @return
*/
public static String get(String key) {
try {
String value = config.getProperty(key);
return value;
} catch (Exception e) {
logger.error("系统参数配置错误========", e);
return null;
}
}
}