import java.io.ByteArrayOutputStream; import java.io.File; import java.io.FileInputStream; import java.io.InputStream; import java.io.OutputStream; import java.net.HttpURLConnection; import java.net.URL; import java.util.HashMap; import java.util.LinkedList; import java.util.List; import java.util.Map; import java.util.UUID;
public class HttpMultipart { public static void main(String[] args) throws Exception { String link = “http://www.xxx.com/upload“; HttpMultipart hm = new HttpMultipart(link).addParameter(“file”, new File(“d:\xxx.doc”)).addParameter(“other”,”somevalue”); String result = new String(hm.send()); hm.clearParameter(); System.out.println(result);
} private URL url;// 链接URL private String boundary = "--------" + UUID.randomUUID().toString().replace("-", "");// HTTP报文分隔符 private Map<String, List<String>> textParams = new HashMap<String, List<String>>();// 字符串表单存储结构 private Map<String, List<File>> fileParams = new HashMap<String, List<File>>();// 文件表单存储结构 public HttpMultipart(String url) throws Exception { this.url = new URL(url); } protected Map<String, List<File>> getFileParams() { return fileParams; } protected Map<String, List<String>> getTextParams() { return textParams; } // 增加一个普通字符串数据到form表单数据中 public HttpMultipart addParameter(String name, String value) { List<String> list = textParams.get(name); if (list == null) { list = new LinkedList<String>(); list.add(value); textParams.put(name, list); } else { list.add(value); } return this; } // 增加一个文件到form表单数据中 public HttpMultipart addParameter(String name, File value) { List<File> list = fileParams.get(name); if (list == null) { list = new LinkedList<File>(); list.add(value); fileParams.put(name, list); } else { list.add(value); } return this; } // 删除指定的字符串参数 public HttpMultipart removeTextParameter(String name) { textParams.remove(name); return this; } // 删除指定的字符串参数（如果是数组，指定数组下标） public HttpMultipart removeTextParameter(String name, int index) { List<String> list = textParams.get(name); if (list != null) { if (list.size() > index) { list.remove(index); } if (list.size() == 0) { textParams.remove(name); } } return this; } // 删除指定的文件参数 public HttpMultipart removeFileParameter(String name) { fileParams.remove(name); return this; } // 删除指定的文件参数（如果是数组，指定数组下标） public HttpMultipart removeFileParameter(String name, int index) { List<File> list = fileParams.get(name); if (list != null) { if (list.size() > index) { list.remove(index); } if (list.size() == 0) { fileParams.remove(name); } } return this; } // 清除字符串参数 public HttpMultipart clearTextParameter() { textParams.clear(); return this; } // 清除文件参数 public HttpMultipart clearFileParameter() { fileParams.clear(); return this; } // 清除所有参数 public HttpMultipart clearParameter() { textParams.clear(); fileParams.clear(); return this; } // 发送数据到服务器，返回一个字节包含服务器的返回结果的数组 public byte[] send() throws Exception { HttpURLConnection connection = (HttpURLConnection) url.openConnection(); long length = getLength(); connection.setDoOutput(true); connection.setUseCaches(false); connection.setConnectTimeout(10000); // 连接超时为10秒 connection.setRequestMethod("POST"); connection.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + boundary); connection.setRequestProperty("Content-Length", length + ""); // connection.setFixedLengthStreamingMode((int) length);//设置上传流大小，防止OutOfMemoryError；但是Int的最大值只支持2G，所以暂时不用； connection.setChunkedStreamingMode(65536);// 设置上传流区块大小，防止OutOfMemoryError connection.connect(); OutputStream o = connection.getOutputStream(); writeFileParams(o); writeTextParams(o); paramsEnd(o); InputStream in = connection.getInputStream(); ByteArrayOutputStream out = new ByteArrayOutputStream(); transfer(in, out, 1024); out.close(); in.close(); connection.disconnect(); return out.toByteArray(); } // 获取一个字符串表单的长度 private long getParamLength(String name, String value) throws Exception { return 49 + boundary.length() + name.length() + value.getBytes().length; } // 获取一个文件表单的长度 private long getParamLength(String name, File value) throws Exception { return 102 + boundary.length() + name.length() + value.getName().getBytes().length + value.length(); } // 获取报文的长度 private long getLength() throws Exception { long length = 0; for (String name : textParams.keySet()) { List<String> list = textParams.get(name); for (String value : list) { length = length + getParamLength(name, value); } } for (String name : fileParams.keySet())