摘要：直接用的上傳文件，通過模擬提交方法具體代碼如下網絡訪問工具默認默認或執行調用地址方法地址請求的與實體對應的信息如執行調用地址方法地址秒連接分鐘讀數據上傳文件表單參數文件參數上傳文件允許同一個屬性上傳多個文件表單參數文件參數調

直接用jdk的HttpURLConnection上傳文件，通過模擬post提交方法

具體代碼如下：

import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Objects;

import org.apache.commons.lang3.StringUtils;
import org.apache.log4j.Logger;

/**
 * http 網絡訪問工具
 *
 * @author wonderful.
 * @version 3.0.0
 */
public class HttpClient {

    private final static Logger LOGGER = Logger.getLogger(HttpClient.class);
    private String method = null;
    private String CONTENT_TYPE = null; //默認
    
    /**
     * 默認POST
     *
     * @return String
     */
    public String getMethod() {
        if (method == null) {
            return "POST";
        }
        return method;
    }

    /**
     *  POST 或 GET 
     *
     * @param method .
     */
    public void setMethod(String method) {
        this.method = method;
    }
    
    /**
     * 執行調用 serviceURL地址 方法
     * @param serviceURL webService地址.
     * @param param String.
     * @param ContentType 請求的與實體對應的MIME信息   如：Content-Type: application/x-www-form-urlencoded,application/json,application/xml  
     * @return String.
     */
    public String pub(String serviceURL, String param,String contentType) {
        CONTENT_TYPE = contentType;
        return pub(serviceURL,param);
    }
    /**
     * 執行調用 serviceURL地址 方法
     * @param serviceURL webService地址.
     * @param param String.
     * @return String.
     */
    public String pub(String serviceURL, String param) {
        URL url = null;
        HttpURLConnection connection = null;
        StringBuffer buffer = new StringBuffer();
        LOGGER.info("request:" + serviceURL + "?" + param);
        try {
            url = new URL(serviceURL);
            connection = (HttpURLConnection) url.openConnection();
            connection.setDoOutput(true);
            connection.setDoInput(true);
            connection.setUseCaches(false);
            connection.setRequestMethod(getMethod());
            connection.setConnectTimeout(5000);//30秒連接
            connection.setReadTimeout(5*60*1000);//5分鐘讀數據
            connection.setRequestProperty("Content-Length", param.length() + "");
            if(CONTENT_TYPE != null){
                connection.setRequestProperty("Content-Type", CONTENT_TYPE);
            }           
            
            OutputStream outputStream = connection.getOutputStream();
            outputStream.write(param.getBytes("UTF-8"));

            BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream(), "UTF-8"));
            String line = "";
            while ((line = reader.readLine()) != null) {
                buffer.append(line);
            }

            reader.close();
        } catch (IOException e) {
            LOGGER.error(e);
        } finally {

            if (connection != null) {
                connection.disconnect();
            }
        }

        LOGGER.info("response:" + buffer.toString());
        return buffer.toString();
    }

    /**
     * 上傳文件
     * 
     * @param serviceURL
     * @param textMap
     *            表單參數
     * @param fileMap
     *            文件參數
     * @return
     * @throws IOException
     */
    public static String formUpload(String serviceURL, Map textMap, Map fileMap) throws IOException {
        Map> tempMap = new HashMap<>();
        if (!Objects.isNull(fileMap) && !fileMap.isEmpty()) {
            Iterator> iter = fileMap.entrySet().iterator();
            while (iter.hasNext()) {
                Map.Entry entry = iter.next();
                String inputName = entry.getKey();
                String inputValue = entry.getValue();
                if (StringUtils.isAnyBlank(inputName, inputValue)) {
                    continue;
                }
                LinkedHashSet values = new LinkedHashSet<>();
                values.add(inputValue);
                tempMap.put(inputName, values);
            }
        }
        return formUploadMulti(serviceURL, textMap, tempMap);
    }

    /**
     * 上傳文件,允許同一個屬性上傳多個文件
     * 
     * @param serviceURL
     * @param textMap
     *            表單參數
     * @param fileMap
     *            文件參數
     * @return
     * @throws IOException
     */
    public static String formUploadMulti(String serviceURL, Map textMap, Map> fileMap) throws IOException {
        LOGGER.trace(String.format("調用文件上傳，傳入參數:serviceURL=%s,textMap=%s,fileMap=%s", serviceURL, textMap, fileMap));
        String res = "";
        HttpURLConnection conn = null;
        OutputStream out = null;
        BufferedReader reader = null;
        String BOUNDARY = "---------------------------" + System.currentTimeMillis(); // boundary就是request頭和上傳文件內容的分隔符
        try {
            URL url = new URL(serviceURL);
            conn = (HttpURLConnection) url.openConnection();
            conn.setConnectTimeout(5000);// 30秒連接
            conn.setReadTimeout(5 * 60 * 1000);// 5分鐘讀數據
            conn.setDoOutput(true);
            conn.setDoInput(true);
            conn.setUseCaches(false);
            conn.setRequestMethod("POST");
            conn.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + BOUNDARY);

            out = new DataOutputStream(conn.getOutputStream());
            // text
            if (!Objects.isNull(textMap) && !textMap.isEmpty()) {
                StringBuffer strBuf = new StringBuffer();
                Iterator> iter = textMap.entrySet().iterator();
                while (iter.hasNext()) {
                    Map.Entry entry = iter.next();
                    String inputName = entry.getKey();
                    String inputValue = entry.getValue();
                    if (StringUtils.isAnyBlank(inputName, inputValue)) {
                        continue;
                    }
                    strBuf.append("
").append("--").append(BOUNDARY).append("
");
                    strBuf.append("Content-Disposition: form-data; name="" + inputName + ""

");
                    strBuf.append(inputValue);
                }
                out.write(strBuf.toString().getBytes());
            }

            // file
            if (!Objects.isNull(fileMap) && !fileMap.isEmpty()) {
                Iterator>> iter = fileMap.entrySet().iterator();
                while (iter.hasNext()) {
                    Entry> entry = iter.next();
                    String inputName = entry.getKey();
                    LinkedHashSet inputValue = entry.getValue();
                    if (StringUtils.isAnyBlank(inputName) || inputValue.isEmpty()) {
                        continue;
                    }
                    for (String filePath : inputValue) {
                        File file = new File(filePath);
                        String filename = file.getName();
                        Path path = Paths.get(filePath);
                        String contentType = Files.probeContentType(path);
                        StringBuffer strBuf = new StringBuffer();
                        strBuf.append("
").append("--").append(BOUNDARY).append("
");
                        strBuf.append("Content-Disposition: form-data; name="" + inputName + ""; filename="" + filename + ""
");
                        strBuf.append("Content-Type:" + contentType + "

");
                        LOGGER.trace(String.format("filename:%s,contentType:%s", filename, contentType));
                        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 = ("
--" + BOUNDARY + "--
").getBytes();
            out.write(endData);
            out.flush();

            // 讀取返回數據
            LOGGER.trace(String.format("http 返回狀態:ResponseCode=%s,ResponseMessage=%s", conn.getResponseCode(), conn.getResponseMessage()));
            StringBuffer strBuf = new StringBuffer();
            reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
            String line = null;
            while ((line = reader.readLine()) != null) {
                strBuf.append(line).append("
");
            }
            res = strBuf.toString();
            LOGGER.trace(String.format("http 返回數據:%s", res));
            reader.close();
            reader = null;
        } catch (IOException e) {
            throw e;
        } finally {
            if (!Objects.isNull(out)) {
                out.close();
                out = null;
            }
            if (!Objects.isNull(reader)) {
                reader.close();
                reader = null;
            }
            if (conn != null) {
                conn.disconnect();
                conn = null;
            }
        }
        return res;
    }
}

上面的兩個方法有待優化，未處理