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本篇文章為大家展示了java中怎么實(shí)現(xiàn)后臺(tái)圖片跨域上傳功能,內(nèi)容簡(jiǎn)明扼要并且容易理解,絕對(duì)能使你眼前一亮,通過這篇文章的詳細(xì)介紹希望你能有所收獲。
在項(xiàng)目開發(fā)的過程中,我們經(jīng)常需要用到圖片上傳操作,傳統(tǒng)的做法是我們將其上傳到項(xiàng)目的所在目錄中,比如說項(xiàng)目的target目錄中,但是由于項(xiàng)目在重啟的過程中,target文件夾下的內(nèi)容會(huì)被全部清空,這意味著如果采用這種方式,那么在測(cè)試環(huán)境與開發(fā)環(huán)境;在每一次的項(xiàng)目重啟的過程中,我們經(jīng)常會(huì)遭遇圖片丟失的情況,這種情況有時(shí)往往很讓人頭疼,因而有一個(gè)圖片服務(wù)器對(duì)于項(xiàng)目的開發(fā)和測(cè)試而言,這是十分必要的。
在采用圖片服務(wù)器的情況下,我們只需要像往常一樣,由前臺(tái)界面將圖片上傳到本地項(xiàng)目服務(wù)器中,然后本地的項(xiàng)目服務(wù)器會(huì)將該圖片的數(shù)據(jù)流寫入到遠(yuǎn)程的圖片服務(wù)器中,由遠(yuǎn)程的圖片服務(wù)器負(fù)責(zé)圖片的存儲(chǔ),最后,遠(yuǎn)程的圖片服務(wù)器會(huì)返回一個(gè)存儲(chǔ)圖片路徑,在本地的服務(wù)器只需要存儲(chǔ)該路徑,在頁面展示的時(shí)候,只需要在前臺(tái)將該圖片路徑展示出來,即可完成對(duì)于遠(yuǎn)程圖片服務(wù)器的調(diào)用。
@ResponseBody @RequestMapping(value="/imgUpLoadNewOneKuaYu") public String imgUpLoadNewOneKuaYu(HttpServletRequest request) throws IOException { String urlStr = "http://localhost:9080/no-js/admin/upload"; Map<String, String> textMap = new HashMap<String, String>(); MultipartHttpServletRequest multiRequest = (MultipartHttpServletRequest) request;//流的數(shù)據(jù)* //取得request中的所有文件名 Iterator<String> iter = multiRequest.getFileNames(); Map<String, InputStream> fileMap = new HashMap<String, InputStream>(); if(iter.hasNext()){ //取得上傳文件 MultipartFile file = multiRequest.getFile(iter.next()); if(file != null){ //取得當(dāng)前上傳文件的文件名稱 String myFileName = file.getOriginalFilename(); InputStream fileInputStream=file.getInputStream(); fileMap.put(myFileName, fileInputStream); } } String ret = FileUpLoadNew.formUpload(urlStr, textMap, fileMap); System.out.println(ret); return ret; }
FileUpLoadNew
package net.sahv.bdyz.util;import java.io.BufferedReader;import java.io.DataInputStream;import java.io.DataOutputStream;import java.io.FileInputStream;import java.io.InputStream;import java.io.InputStreamReader;import java.io.OutputStream;import java.net.HttpURLConnection;import java.net.URL;import java.util.Iterator;import java.util.Map;public class FileUpLoadNew { /** * @param urlStr * @param textMap * @param fileMap * @return */ public static String formUpload(String urlStr, Map<String, String> textMap, Map<String, InputStream> fileMap) { String res = ""; HttpURLConnection conn = null; String BOUNDARY = "---------------------------123821742118716"; //boundary就是request頭和上傳文件內(nèi)容的分隔符 try { URL url = new URL(urlStr); conn = (HttpURLConnection) url.openConnection(); conn.setConnectTimeout(5000); conn.setReadTimeout(30000); conn.setDoOutput(true); conn.setDoInput(true); conn.setUseCaches(false); conn.setRequestMethod("POST"); conn.setRequestProperty("Connection", "Keep-Alive"); conn.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows; U; Windows NT 6.1; zh-CN; rv:1.9.2.6)"); conn.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + BOUNDARY); OutputStream out = new DataOutputStream(conn.getOutputStream()); // textMap:如果傳送的是文本內(nèi)容 if (textMap != null) { StringBuffer strBuf = new StringBuffer(); Iterator<Map.Entry<String, String>> iter = textMap.entrySet().iterator(); while (iter.hasNext()) { Map.Entry<String, String> entry = iter.next(); String inputName = (String) entry.getKey(); String inputValue = (String) entry.getValue(); if (inputValue == null) { continue; } strBuf.append("\r\n").append("--").append(BOUNDARY).append("\r\n"); strBuf.append("Content-Disposition: form-data; name=\"" + inputName + "\"\r\n\r\n"); strBuf.append(inputValue); } out.write(strBuf.toString().getBytes()); } //fileMap:如果傳送的是文件流 if (fileMap != null) { Iterator<Map.Entry<String, InputStream>> iter = fileMap.entrySet().iterator(); while (iter.hasNext()) { Map.Entry<String, InputStream> entry = iter.next(); String inputName = (String) entry.getKey(); FileInputStream inputValue = (FileInputStream) entry.getValue(); if (inputValue == null) { continue; } String contentType = "image/png"; StringBuffer strBuf = new StringBuffer(); strBuf.append("\r\n").append("--").append(BOUNDARY).append("\r\n"); strBuf.append("Content-Disposition: form-data; name=\"" + inputName + "\"; filename=\"" + inputName + "\"\r\n"); strBuf.append("Content-Type:" + contentType + "\r\n\r\n"); out.write(strBuf.toString().getBytes()); DataInputStream in = new DataInputStream(inputValue); int bytes = 0; byte[] bufferOut = new byte[1024]; while ((bytes = in.read(bufferOut)) != -1) { out.write(bufferOut, 0, bytes); } in.close(); } } byte[] endData = ("\r\n--" + BOUNDARY + "--\r\n").getBytes(); out.write(endData); out.flush(); out.close(); // 讀取返回?cái)?shù)據(jù) StringBuffer strBuf = new StringBuffer(); BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream())); String line = null; while ((line = reader.readLine()) != null) { strBuf.append(line).append("\n"); } res = strBuf.toString(); reader.close(); reader = null; } catch (Exception e) { System.out.println("發(fā)送POST請(qǐng)求出錯(cuò)。" + urlStr); e.printStackTrace(); } finally { //最后關(guān)閉鏈接 if (conn != null) { conn.disconnect(); conn = null; } } return res; }}
package com.lyc.noJs.controller;import com.google.common.base.Splitter;import com.lyc.noJs.util.ImgMD5Util;import lombok.extern.slf4j.Slf4j;import org.joda.time.DateTime;import org.springframework.stereotype.Controller;import org.springframework.util.MultiValueMap;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestMethod;import org.springframework.web.bind.annotation.ResponseBody;import org.springframework.web.multipart.MultipartFile;import org.springframework.web.multipart.MultipartHttpServletRequest;import java.io.*;import java.security.NoSuchAlgorithmException;import java.util.Iterator;import java.util.List;import java.util.Map;import java.util.Set;@Controller@RequestMapping("/admin")@Slf4jpublic class UploadController { @ResponseBody @RequestMapping(value = "/upload",method= RequestMethod.POST) public String upload(MultipartHttpServletRequest multiRequest) throws UnsupportedEncodingException { //圖片文件夾根路徑 //TODO //這里的父路徑暫時(shí)是target路徑,在真實(shí)上線后,應(yīng)該將其改成其它路徑。 String uploadFilePath = multiRequest.getServletContext().getRealPath("/upload/"); //圖片文件夾日期路徑 String datePath = getDateFolderName() + "\\"; //圖片名稱 String imagePath = saveImage(multiRequest,uploadFilePath,datePath); log.info(imagePath); return imagePath; } /** * 保存圖片 * @param multiRequest * @param uploadFilePath * @param datePath * @return * @throws UnsupportedEncodingException */ public String saveImage(MultipartHttpServletRequest multiRequest,String uploadFilePath,String datePath) throws UnsupportedEncodingException { String imageNameHead = createImageNameHead(); String imageName = ""; //設(shè)置圖片的瀏覽為utf-8格式,防止圖片名稱亂碼 multiRequest.setCharacterEncoding("utf-8"); MultiValueMap<String, MultipartFile> multiFileMap = multiRequest.getMultiFileMap(); Set<Map.Entry<String, List<MultipartFile>>> set = multiFileMap.entrySet(); Iterator<Map.Entry<String, List<MultipartFile>>> iterator = set.iterator(); while(iterator.hasNext()){ Map.Entry<String, List<MultipartFile>> entry = iterator.next(); String imageNameEnd = getImageNameEnd(entry); imageName = imageNameHead + "." + imageNameEnd; List<MultipartFile> multipartFileList = entry.getValue(); MultipartFile multipartFile = multipartFileList.get(0); //圖片文件的包路徑 String imagePath = uploadFilePath + datePath; //如果文件夾創(chuàng)建失敗,則返回null if(makeParentFolder(imagePath)){ //如果文件夾創(chuàng)建失敗,則返回false,否則返回true //圖片文件的路徑 String imgFile = imagePath + imageName; //如果文件創(chuàng)建失敗,則返回null if(!makeImage(multipartFile,imgFile)){ //當(dāng)文件創(chuàng)建失敗時(shí),返回false,否則返回true return null; } } else { return null; } } return datePath + imageName; } /** * 創(chuàng)建圖片 * @param multipartFile * @param imgFile * @return */ public boolean makeImage(MultipartFile multipartFile,String imgFile){ File tempFile = new File(imgFile); if(tempFile != null){ //如果原圖片不存在,則生成圖片 if(!tempFile.exists()){ try { log.info("1"); multipartFile.transferTo(tempFile); } catch (IOException e) { e.printStackTrace(); } } return true; } return false; } /** * 創(chuàng)建父文件路徑 * @param imagePath * @return */ public boolean makeParentFolder(String imagePath){ File parentFile = new File(imagePath); if(parentFile != null){ while (!parentFile.exists()){ //批量生成全部的父文件路徑 parentFile.mkdirs(); } return true; } return false; } /** * 文件夾生成規(guī)則 */ public String getDateFolderName(){ DateTime dataTime = new DateTime(); String currentDate = dataTime.toString("yyyy\\MM\\dd"); return currentDate; } /** * 創(chuàng)建圖片文件的文件名 * @return */ public String createImageNameHead(){ DateTime dataTime = new DateTime(); return String.valueOf(dataTime.getMillis()); }}
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