JavaEE上传文件
一、搭建环境
1、本文是在搭建web环境下，上传功能的，可以参考下搭建web环境
Maven配置SpringMVC4+Spring4+Mybatis3环境
2、需要添加上传文件依赖的jar包
<!-- Apache Commons FileUpload --> <!-- http://mvnrepository.com/artifact/commons-fileupload/commons-fileupload --> <dependency> <groupId>commons-fileupload</groupId> <artifactId>commons-fileupload</artifactId> <version>1.3.1</version> </dependency> <!-- Apache Commons IO --> <!-- http://mvnrepository.com/artifact/commons-io/commons-io --> <dependency> <groupId>commons-io</groupId> <artifactId>commons-io</artifactId> <version>2.4</version> </dependency>
二、使用SpringMVC上传文件
1、在初始化Spring容器中添加上传配置
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <!-- Maximum file size: 1MB --> <!-- 1MB = 125000 Byte --> <!--<property name="maxUploadSize" value="125000"/>--> <property name="defaultEncoding" value="utf-8"/> </bean>
2、新建FileUploadController类
package com.moy.whymoy.test.controller; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.ResponseBody; import org.springframework.web.multipart.MultipartFile; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.*; /** * [Project]:whymoy <br/> * [Email]:moy25@foxmail.com <br/> * [Date]:2018/3/13 <br/> * [Description]: <br/> * * @author YeXiangYang */ @Controller @RequestMapping("/upload") public class FileUploadController { @RequestMapping("/doUpload") @ResponseBody public String uploadFileHandler(HttpServletRequest request, HttpServletResponse response, @RequestParam(value = "files") MultipartFile[] files) { String realPath = request.getServletContext().getRealPath("upload"); File uploadRootPath = new File(realPath); if (!uploadRootPath.exists()) { uploadRootPath.mkdirs(); } StringBuilder sb = new StringBuilder(); for (int i = 0; i < files.length; i++) { MultipartFile file = files[i]; String originalFilename = file.getOriginalFilename(); try { File serverFile = new File(uploadRootPath, originalFilename); try (BufferedInputStream bis = new BufferedInputStream(file.getInputStream()); BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(serverFile))) { byte[] buffer = new byte[1024]; int len = 0; while (-1 != (len = bis.read(buffer))) { bos.write(buffer, 0, len); } } sb.append("Upload File :").append(serverFile).append("\n"); } catch (IOException e) { e.printStackTrace(); } } return sb.toString(); } }
3、在WEB-INF同级目录下，新建uploadFile.html（在同一站点下）
<html> <head> <title>uploadOneFile</title> </head> <body> <form method="POST" action="upload/doUpload.do" enctype="multipart/form-data"> File to upload: <input type="file" name="files"><br/> <input type="submit" value="Upload"> </form> </body> </html>
4、运行tomcat7插件访问uploadFile.html页面，测试上传
三、使用servlet上传
1、新建UploadServlet类
package com.moy.whymoy.test.servlet; import org.apache.commons.fileupload.FileItem; import org.apache.commons.fileupload.FileUploadException; import org.apache.commons.fileupload.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.File; import java.io.IOException; import java.io.PrintWriter; import java.util.List; import java.util.Objects; /** * [Project]:whymoy <br/> * [Email]:moy25@foxmail.com <br/> * [Date]:2018/3/13 <br/> * [Description]: <br/> * * @author YeXiangYang */ @WebServlet(urlPatterns = "/upload/servlet") public class UploadServlet extends HttpServlet { // 上传目录 private static String UPLOAD_DIR = "upload"; // 默认编码 private static String DEFAULT_ENCODING = "utf-8"; // 内存临界值 private static final int MEMORY_THRESHOLD = 1024 * 1024 * 3; // 3MB // 上传文件最大值 private static final int MAX_FILE_SIZE = 1024 * 1024 * 40; // 40MB // 请求最大值 private static final int MAX_REQUEST_SIZE = 1024 * 1024 * 50; // 50MB @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { PrintWriter writer = resp.getWriter(); if (!ServletFileUpload.isMultipartContent(req)) { writer.println("需要为类型为:enctype=multipart/form-data"); return; } DiskFileItemFactory factory = new DiskFileItemFactory(); factory.setSizeThreshold(MEMORY_THRESHOLD); ServletFileUpload servletFileUpload = new ServletFileUpload(factory); servletFileUpload.setSizeMax(MAX_REQUEST_SIZE); servletFileUpload.setFileSizeMax(MAX_FILE_SIZE); servletFileUpload.setHeaderEncoding(DEFAULT_ENCODING); String realPath = req.getServletContext().getRealPath(UPLOAD_DIR); File uploadRootPath = new File(realPath); if (!uploadRootPath.exists()) { uploadRootPath.mkdirs(); } try { List<FileItem> fileItems = servletFileUpload.parseRequest(req); if (Objects.nonNull(fileItems)) { for (FileItem eachItem : fileItems) { if (!eachItem.isFormField()) { String fileName = new File(eachItem.getName()).getName(); File serverFile = new File(uploadRootPath, fileName); eachItem.write(serverFile); writer.println("Upload File :" + serverFile); } } } } catch (FileUploadException e) { e.printStackTrace(); } catch (Exception e) { e.printStackTrace(); } } }
2、在WEB-INF同级目录下，新建servletUploadFile.html（在同一站点下）
<html>
<head>
<title>uploadOneFile</title>
</head>
<body>
<form method="POST" action="upload/servlet" enctype="multipart/form-data">
File to upload: <input type="file" name="files"><br/>
<input type="submit" value="Upload">
</form>
</body>
</html>
3、运行tomcat7插件访问servletUploadFile.html页面，测试上传
四、异步上传
1、在WEB-INF同级目录下，添加jquery.js库和新建ajax.html（在同一站点下）
<!DOCTYPE html>
<html>
<head>
<title>test</title>
<script type="text/javascript" src="./jquery.js"></script>
</head>
<body>
<form id="form1" method="POST" action="http://192.168.182.130:8080/whymoy/upload/servlet" enctype="multipart/form-data">
File to upload: <input type="file" name="files"><br/>
<input type="submit" value="表单同步上传">
</form><br/>
<input id="ajaxUpload" type="button" value="异步上传"> <br/>
<div id="result" style="color: red">
</div>
<script type="text/javascript">
$(function(){
$("#ajaxUpload").click(function(){
$.ajax({
url:"http://192.168.182.130:8080/whymoy/upload/doUpload.do",
type: 'POST',
cache: false,
data: new FormData($('#form1')[0]),
processData: false,
contentType: false,
success:function(data){
$("#result").text(data);
}
})
});
});
</script>
</body>
</html>
2、运行tomcat7插件访问ajax.html页面，测试上传
五、跨域异步上传
1、第四步是可以满足异步上传的，只是进入不了回调函数，想要进入回调函数，可以响应时添加对应的响应头，可以参考
六、也可以直接使用httpClient，获取文件流，直接上传
1、添加依赖
<dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> <version>4.5.3</version> </dependency> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpmime</artifactId> <version>4.5.3</version> </dependency>
2、测试代码
package com.moy.whymoy.test; import org.apache.http.HttpEntity; import org.apache.http.client.methods.CloseableHttpResponse; import org.apache.http.client.methods.HttpPost; import org.apache.http.entity.mime.MultipartEntityBuilder; import org.apache.http.impl.client.CloseableHttpClient; import org.apache.http.impl.client.HttpClients; import org.apache.http.util.EntityUtils; import java.io.File; import java.io.IOException; /** * [Project]:whymoy <br/> * [Email]:moy25@foxmail.com <br/> * [Date]:2018/3/14 <br/> * [Description]: <br/> * * @author YeXiangYang */ public class Main { public static void main(String[] args) throws IOException { try (CloseableHttpClient httpClient = HttpClients.createDefault();) { File file = new File("pom.xml"); MultipartEntityBuilder entityBuilder = MultipartEntityBuilder.create(); entityBuilder.addBinaryBody("files", file); HttpEntity httpEntity = entityBuilder.build(); String uploadUrl = "http://localhost:8080/whymoy/upload/doUpload.do"; HttpPost httpPost = new HttpPost(uploadUrl); httpPost.setEntity(httpEntity); CloseableHttpResponse response = httpClient.execute(httpPost); String result = EntityUtils.toString(response.getEntity()); System.out.println(result); } } }
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