下面是需要传入的参数的格式及要求：

package com.quanzhen.test;

import java.io.BufferedReader;

import java.io.DataInputStream;

import java.io.DataOutputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.net.HttpURLConnection;

import java.net.URL;

import java.util.HashMap;

import java.util.Iterator;

import java.util.Map;

import javax.activation.MimetypesFileTypeMap;

/**

* java通过模拟post方式提交表单实现图片上传功能实例

* 其他文件类型可以传入 contentType 实现

*/

public class Test {

public static void main(String[] args) {

testUploadImage();

}

/**

* 测试上传png图片

*

*/

public static void testUploadImage(){

String url = "http://localhost:8080/reader/book/insertAPIBook";

String lunboimg = "C:/Users/Administrator/Desktop/123.jpg";

String reader = "C:/Users/Administrator/Desktop/reader.txt";

Map textMap = new HashMap();

//可以设置多个input的name，value

textMap.put("author", "谢霆锋");

textMap.put("bookName", "坏蛋是怎么练成的");

//设置file的name，路径

Map fileMap = new HashMap();

fileMap.put("lunboimg", lunboimg);

fileMap.put("file", reader);

String contentType = "";//image/png

String ret = formUpload(url, textMap, fileMap,contentType);

System.out.println(ret);

//{"status":"0","message":"add succeed","baking_url":"group1\/M00\/00\/A8\/CgACJ1Zo-LuAN207AAQA3nlGY5k151.png"}

}

/**

* 上传图片

* @param urlStr

* @param textMap

* @param fileMap

* @param contentType 没有传入文件类型默认采用application/octet-stream

* contentType非空采用filename匹配默认的图片类型

* @return 返回response数据

*/

@SuppressWarnings("rawtypes")

public static String formUpload(String urlStr, Map textMap,

Map fileMap,String contentType) {

String res = "";

HttpURLConnection conn = null;

// boundary就是request头和上传文件内容的分隔符

String BOUNDARY = "---------------------------123821742118716";

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());

// text

if (textMap != null) {

StringBuffer strBuf = new StringBuffer();

Iterator iter = textMap.entrySet().iterator();

while (iter.hasNext()) {

Map.Entry entry = (Map.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());

}

// file

if (fileMap != null) {

Iterator iter = fileMap.entrySet().iterator();

while (iter.hasNext()) {

Map.Entry entry = (Map.Entry) iter.next();

String inputName = (String) entry.getKey();

String inputValue = (String) entry.getValue();

if (inputValue == null) {

continue;

}

File file = new File(inputValue);

String filename = file.getName();

//没有传入文件类型，同时根据文件获取不到类型，默认采用application/octet-stream

contentType = new MimetypesFileTypeMap().getContentType(file);

//contentType非空采用filename匹配默认的图片类型

if(!"".equals(contentType)){

if (filename.endsWith(".png")) {

contentType = "image/png";

}else if (filename.endsWith(".jpg") || filename.endsWith(".jpeg") || filename.endsWith(".jpe")) {

contentType = "image/jpeg";

}else if (filename.endsWith(".gif")) {

contentType = "image/gif";

}else if (filename.endsWith(".ico")) {

contentType = "image/image/x-icon";

}

}

if (contentType == null || "".equals(contentType)) {

contentType = "application/octet-stream";

}

StringBuffer strBuf = new StringBuffer();

strBuf.append("\r\n").append("--").append(BOUNDARY)

.append("\r\n");

strBuf.append("Content-Disposition:form-data;name=\""

+ inputName + "\";filename=\"" + filename

+ "\"\r\n");

strBuf.append("Content-Type:" + contentType + "\r\n\r\n");

out.write(strBuf.toString().getBytes());

DataInputStream in = new DataInputStream(

new FileInputStream(file));

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();

// 读取返回数据

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("发送POST请求出错。" + urlStr);

e.printStackTrace();

} finally {

if (conn != null) {

conn.disconnect();

conn = null;

}

}

return res;

}

}

下面是Java后台接收的接口

参数是以流的形式，所以后台也要用流的形式接收

@RequestMapping(value = "/insertAPIBook", method = RequestMethod.POST)

@ResponseBody

public String insertAPIBook(DefaultMultipartHttpServletRequest request) {

try {

// 用DefaultMultipartHttpServletRequest来接收，参数会自动封装到request作用域中

//普通参数，直接用request.getParameter("bookName")，文件接收如下

Book book = new Book();

if(StringUtil.isNotEmpty(request.getParameter("bookName"))){

book.setBookName(request.getParameter("bookName"));

}

if(StringUtil.isNotEmpty(request.getParameter("author"))){

book.setAuthor(request.getParameter("author"));

}

MultiValueMap mvmFs = request.getMultiFileMap();

MultipartFile file=null;

MultipartFile lunboimg=null;

MultipartFile headimg=null;

for (String key : mvmFs.keySet()) {

System.out.println("----属性名---" + key);

if("file".equals(key)){

file=request.getFile(key);

}

if("lunboimg".equals(key)){

lunboimg=request.getFile(key);

}

if("headimg".equals(key)){

headimg=request.getFile(key);

}

}

//下面就是调用和form表单提交一样的接口，没啥区别

bookServiceImpl.insertBook(everychapterfee, paychapter, book, file, lunboimg, headimg, request, tag);

return "ok";

}catch (Exception e){

e.printStackTrace();

return "fail";

}

}

这就可以接收文件了，亲测是可以的，切记不要把参数拼接在url里面，否则会出现乱码