Android想服务器传图片，透过流的方式。还有读取服务器图片（文件），也通过流的方式。

/**
 * Created by Administrator on 2016/7/19.
 */

import android.util.Log;

import com.gtercn.asPolice.net.HttpsTrustManager;

import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.security.KeyManagementException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.UUID;

import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSession;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManager;

/**
 *
 * 上传头像工具类
 * Https协议的
 * @author spring sky Email:vipa1888@163.com QQ:840950105 MyName:石明政
 */
public class UpdateImage {
    private static final String TAG = "uploadFile";
    private static final int TIME_OUT = 10 * 1000; // 超时时间
    private static final String CHARSET = "utf-8"; // 设置编码

    /**
     * Android上传文具到服务端
     *
     * @param file
     *            需要上传的文件
     * @param RequestURL
     *            请求的rul
     * @return 返回响应的内容
     */
    public static String uploadFile(File file, String RequestURL) {
        String result = null;
        String BOUNDARY = UUID.randomUUID().toString(); // 边界标识 随机生成
        String PREFIX = "--", LINE_END = "
";
        String CONTENT_TYPE = "multipart/form-data"; // 内容类型

        try {
            URL url = new URL(RequestURL);
            HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();
            conn.setSSLSocketFactory(getSocketFactoryCertificate());
            conn.setHostnameVerifier(getHostnameVerifier());
            conn.setReadTimeout(TIME_OUT);
            conn.setConnectTimeout(TIME_OUT);
            conn.setDoInput(true); // 允许输入流
            conn.setDoOutput(true); // 允许输出流
            conn.setUseCaches(false); // 不允许使用缓存
            conn.setRequestMethod("POST"); // 请求方式
            conn.setRequestProperty("Charset", CHARSET); // 设置编码
            conn.setRequestProperty("connection", "keep-alive");
            conn.setRequestProperty("Content-Type", CONTENT_TYPE + ";boundary="
                    + BOUNDARY);
            conn.setRequestProperty("api-version", "1.0");
            if (file != null) {
                /**
                 * 当文件不为空，把文件包装并且上传
                 */
                Log.e("======","====DataOutputStream===");
                DataOutputStream dos = new DataOutputStream(conn.getOutputStream());
                StringBuffer sb = new StringBuffer();
                sb.append(PREFIX);
                sb.append(BOUNDARY);
                sb.append(LINE_END);
                /**
                 * 这里重点注意： name里面的值为服务端需要key 只有这个key 才可以得到对应的文件
                 * filename是文件的名字，包含后缀名的 比如:abc.png
                 */
                sb.append("Content-Disposition: form-data; name="avatar"; filename=""
                        + file.getName() + """ + LINE_END);
                        sb.append("Content-Type: application/octet-stream; charset="
                                + CHARSET + LINE_END);
                sb.append(LINE_END);
                dos.write(sb.toString().getBytes());
                InputStream is = new FileInputStream(file);
                byte[] bytes = new byte[1024];
                int len = 0;
                while ((len = is.read(bytes)) != -1) {
                    dos.write(bytes, 0, len);
                }
                is.close();
                dos.write(LINE_END.getBytes());
                byte[] end_data = (PREFIX + BOUNDARY + PREFIX + LINE_END)
                        .getBytes();
                dos.write(end_data);
                dos.flush();
                Log.e("======","====flush===");

                /**
                 * 获取响应码 200=成功 当响应成功，获取响应的流
                 */
                int res = conn.getResponseCode();
                Log.e("========", "response code:" + res);
                 if(res==200)
                 {
                Log.e(TAG, "request success");
                InputStream input = conn.getInputStream();
                StringBuffer sb1 = new StringBuffer();
                int ss;
                while ((ss = input.read()) != -1) {
                    sb1.append((char) ss);
                }
                result = sb1.toString();
                Log.e(TAG, "result : " + result);
                 }
                 else{
                 Log.e(TAG, "request error");
                 }
            }
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }
    private static SSLSocketFactory getSocketFactoryCertificate(){

//        String keyStoreType = "BKS";
//        int keyStoreResId = R.raw.cert;
        try {
/*            CertificateFactory certificateFactory = CertificateFactory.getInstance("X.509");
            // cert is under R.raw.cert
            InputStream inputStream = ContextService.getInstance().getContext().
                    getResources().openRawResource(keyStoreResId);//(R.raw.cert);
            Certificate certificate = certificateFactory.generateCertificate(inputStream);
            inputStream.close();

            if(keyStoreType == null || keyStoreType.length() == 0){
                keyStoreType = KeyStore.getDefaultType();
            }
            //BKS
            KeyStore trustStore = KeyStore.getInstance(keyStoreType);
            trustStore.load(null, null);
            trustStore.setCertificateEntry("ca",certificate);

            String tmfAlgorithm = TrustManagerFactory.getDefaultAlgorithm();
            TrustManagerFactory tmf = TrustManagerFactory.getInstance(tmfAlgorithm);
            tmf.init(trustStore);

//            TrustManager[] trustManagers = new TrustManager[]{new HttpsTrustManager(tmf.getTrustManagers())};
            TrustManager[] trustManagers = getWrappedTrustManagers(tmf.getTrustManagers());*/

            TrustManager[] trustManagers = new TrustManager[]{new HttpsTrustManager()};
            SSLContext ssLContext = SSLContext.getInstance("TLS");
            ssLContext.init(null, trustManagers, new SecureRandom());

            return ssLContext.getSocketFactory();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (KeyManagementException e) {
            e.printStackTrace();
        }
        return null;
    }

    private static HostnameVerifier getHostnameVerifier() {
        return new HostnameVerifier() {
            @Override
            public boolean verify(String hostname, SSLSession session) {
                //return true; // verify always returns true, which could cause insecure network traffic due to trusting TLS/SSL server certificates for wrong hostnames
                HostnameVerifier hv = HttpsURLConnection.getDefaultHostnameVerifier();
                return true;//hv.verify("localhost", session);
            }
        };
    }

}

import android.util.Log;

import com.gtercn.asPolice.net.HttpsTrustManager;

import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.security.KeyManagementException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.UUID;

import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSession;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManager;

/**
 *
 * 上传头像工具类
 *Http协议的
 * @author spring sky Email:vipa1888@163.com QQ:840950105 MyName:石明政
 */
public class UpdateImage {
    private static final String TAG = "uploadFile";
    private static final int TIME_OUT = 10 * 1000; // 超时时间
    private static final String CHARSET = "utf-8"; // 设置编码

    /**
     * Android上传文具到服务端
     *
     * @param file
     *            需要上传的文件
     * @param RequestURL
     *            请求的rul
     * @return 返回响应的内容
     */
    public static String uploadFile(File file, String RequestURL) {
        String result = null;
        String BOUNDARY = UUID.randomUUID().toString(); // 边界标识 随机生成
        String PREFIX = "--", LINE_END = "
";
        String CONTENT_TYPE = "multipart/form-data"; // 内容类型

        try {
            URL url = new URL(RequestURL);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setReadTimeout(TIME_OUT);
            conn.setConnectTimeout(TIME_OUT);
            conn.setDoInput(true); // 允许输入流
            conn.setDoOutput(true); // 允许输出流
            conn.setUseCaches(false); // 不允许使用缓存
            conn.setRequestMethod("POST"); // 请求方式
            conn.setRequestProperty("Charset", CHARSET); // 设置编码
            conn.setRequestProperty("connection", "keep-alive");
            conn.setRequestProperty("Content-Type", CONTENT_TYPE + ";boundary="
                    + BOUNDARY);
            conn.setRequestProperty("api-version", "1.0"); //请求头，根据要求要还是不要
            if (file != null) {
                /**
                 * 当文件不为空，把文件包装并且上传
                 */
                Log.e("======","====DataOutputStream===");
                DataOutputStream dos = new DataOutputStream(conn.getOutputStream());
                StringBuffer sb = new StringBuffer();
                sb.append(PREFIX);
                sb.append(BOUNDARY);
                sb.append(LINE_END);
                /**
                 * 这里重点注意： name里面的值为服务端需要key 只有这个key 才可以得到对应的文件
                 * filename是文件的名字，包含后缀名的 比如:abc.png
                 */
                sb.append("Content-Disposition: form-data; name="avatar"; filename=""
                        + file.getName() + """ + LINE_END);
                        sb.append("Content-Type: application/octet-stream; charset="
                                + CHARSET + LINE_END);
                sb.append(LINE_END);
                dos.write(sb.toString().getBytes());
                InputStream is = new FileInputStream(file);
                byte[] bytes = new byte[1024];
                int len = 0;
                while ((len = is.read(bytes)) != -1) {
                    dos.write(bytes, 0, len);
                }
                is.close();
                dos.write(LINE_END.getBytes());
                byte[] end_data = (PREFIX + BOUNDARY + PREFIX + LINE_END)
                        .getBytes();
                dos.write(end_data);
                dos.flush();
                Log.e("======","====flush===");

                /**
                 * 获取响应码 200=成功 当响应成功，获取响应的流
                 */
                int res = conn.getResponseCode();
                Log.e("========", "response code:" + res);
                 if(res==200)
                 {
                Log.e(TAG, "request success");
                InputStream input = conn.getInputStream();
                StringBuffer sb1 = new StringBuffer();
                int ss;
                while ((ss = input.read()) != -1) {
                    sb1.append((char) ss);
                }
                result = sb1.toString();
                Log.e(TAG, "result : " + result);
                 }
                 else{
                 Log.e(TAG, "request error");
                 }
            }
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }

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import android.util.Log;

import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;

/**
 * Created by Administrator on 2016/7/20.
 */
public class DownloadPicture {
    //加载图片
    public static File getdFile(String path, String filepath) throws Exception {
        URL url = new URL(path);//
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();//从网络获得链接
        connection.setRequestMethod("GET");//获得
        connection.setConnectTimeout(5000);//设置超时时间为5s
        connection.setRequestProperty("api-version", "1.0");
        if (connection.getResponseCode() == 200)//检测是否正常返回数据请求 详情参照http协议
        {
            InputStream is = connection.getInputStream();//获得输入流
            File file = new File(filepath);//新建一个file文件
            FileOutputStream fos = new FileOutputStream(file);//对应文件建立输出流
            byte[] buffer = new byte[1024];//新建缓存  用来存储 从网络读取数据 再写入文件
            int len = 0;
            while ((len = is.read(buffer)) != -1) {//当没有读到最后的时候
                fos.write(buffer, 0, len);//将缓存中的存储的文件流秀娥问file文件
            }
            fos.flush();//将缓存中的写入file
            fos.close();
            is.close();//将输入流 输出流关闭
            Log.e("========", "++++++file++++" + file);
            return file;
        }else{
            Log.e("======","-----getResponseCode----"+connection.getResponseCode());
            return null;
        }


    }


}