java-HttpGetPost-图片字节流上传

在java程序开发中经常用到与服务端的交互工作，主要的就是传递相应的参数请求从而获取到对应的结果加以处理

可以使用Get请求与Post请求，注意！这里的Get请求不是通过浏览器界面而是在程序代码中设置的，达到Get请求的目的，具体请详见下列描述

以下get与post请求需要引入的包:

import java.io.IOException;
import java.io.InputStream;
import java.net.URLDecoder;

import org.apache.commons.io.output.ByteArrayOutputStream;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.StringEntity;
import org.apache.http.entity.mime.MultipartEntityBuilder;
import org.apache.http.entity.mime.content.StringBody;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

Get请求:

/**
     * 正常简易的使用HttpGet来向服务端发送Get请求传递的参数直接在url后面拼装上就可以了
     * @param httpUrl
     */
    public static String httpGet(String httpUrl){
        
        httpUrl ="http://192.168.199.138/weixin/test.php?appid=appidaaaa&secret=secretbbbb";
        HttpGet httpGet = new HttpGet(httpUrl);
        CloseableHttpResponse  chResponse = null;
        String result = null;
        try {
            chResponse = HttpClients.createDefault().execute(httpGet);
            if(chResponse.getStatusLine().getStatusCode()==200){
                result = EntityUtils.toString(chResponse.getEntity());
            }
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if(chResponse !=null){
                try {
                    chResponse.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        if(result !=null){
            System.out.println("有结果返回result=="+result);
            return result;
        }else{
            System.out.println("请求没有结果返回");
            return "";
        }
    }
    
    
    
    /**
     * 显示的来调用HttpGet这里的发送执行execut与上面简易方法有不同,
     * 传递的参数直接拼装在url上传递即可
     * @param httpUrl
     * @return
     */
    @SuppressWarnings("deprecation")
    public static String httpGetShow(String httpUrl){
        
        //httpUrl = "";
        DefaultHttpClient client = new DefaultHttpClient();
        HttpResponse response =null;
        String result = null; 
        try {
            
            //发送get请求
            HttpGet httpGet = new HttpGet(httpUrl); //不同之处
            response= client.execute(httpGet);
            if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
               result = EntityUtils.toString(response.getEntity());
                httpUrl = URLDecoder.decode(httpUrl, "UTF-8");
            }
        } catch (IOException e) {
           e.printStackTrace();
        }finally {
            client.close();
        }
        if(result !=null){
            return result;
        }else{
            return "";
        }
    }

 Post请求:

/**
     * 不显示的使用HttpPost就会默认提交请求的方式为post,
     * 传递的参数为以key:value的形式来传递参数
     * @param httpUrl
     * @param imagebyte 可以传递图片等文件,以字节数组的形式传递
     */
    @SuppressWarnings({ "deprecation" })
    public static String httpPost(String httpUrl,byte[] imagebyte){
        
        httpUrl="http://192.168.199.138/weixin/test.php";
        HttpPost httpPost = new HttpPost(httpUrl);
        ByteArrayBody image = new ByteArrayBody(imagebyte,ContentType.APPLICATION_JSON,"image.jpg");//传递图片的时候可以通过此处上传image.jpg随便给出即可
        
        String appid = "appid";
        String secret = "secret";
        
        StringBody appidbody = new StringBody(appid,ContentType.APPLICATION_JSON);
        StringBody secretbody = new StringBody(secret,ContentType.APPLICATION_JSON);
        MultipartEntityBuilder me = MultipartEntityBuilder.create();
        me.addPart("image", image)//image参数为在服务端获取的key通过image这个参数可以获取到传递的字节流,这里不一定就是image,你的服务端使用什么这里就对应给出什么参数即可
        .addPart("appid",appidbody )
        .addPart("secret", secretbody);
        
        DefaultHttpClient client= new DefaultHttpClient(); 
        HttpEntity reqEntity = me.build();
        httpPost.setEntity(reqEntity);
        HttpResponse responseRes = null;
        try {
            responseRes=client.execute(httpPost);
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            client.close();
        }
        
        int status = responseRes.getStatusLine().getStatusCode();
        String resultStr =null;
        if (status == 200) { 
            byte[] content;
            try {
                content = getContent(responseRes);
                resultStr = new String(content,"utf-8");
                System.out.println("httpPost返回的结果==:"+resultStr);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }    
        
        if(resultStr !=null){
            return resultStr;
        }else{
            return "";
        }
    }
    
    /**
     * 显示的调用HttpPost来使用post方式提交请求,并且将请求的参数提前拼装成json字符串,
     * 直接使用StringEntity来发送参数不必要再使用key:value的形式来设置请求参数,
     * 在服务端使用request.getInputStream()来把request中的发送过来的json字符串解析出来,
     * 就是因为使用StringEntity来包装了传递的参数
     * @param httpUrl
     * @param jsonParam
     */
    @SuppressWarnings({ "resource", "deprecation" })
    public static String httpPostShow(String httpUrl,String jsonParam){
        
        httpUrl="http://192.168.199.138/weixin/test.php";
        jsonParam="{"appid":"appidbbbb33333","secret":"secretaaaaa3333"}";//拼装一个json串
        
        DefaultHttpClient httpClient = new DefaultHttpClient();
        
        //这里就是显示的调用post来设置使用post提交请求
        HttpPost method = new HttpPost(httpUrl);
        String result = null;
        try {
            if (null != jsonParam) {
                //解决中文乱码问题
                StringEntity entity = new StringEntity(jsonParam.toString(), "utf-8");//这个StringEntity可以在服务端不用key:value形式来接收,可以request.getInputStream()来获取处理整个请求然后解析即可
                entity.setContentEncoding("UTF-8");
                entity.setContentType("application/json");
                method.setEntity(entity);
            }
            HttpResponse response = httpClient.execute(method);
            httpUrl = URLDecoder.decode(httpUrl, "UTF-8");
            if (response.getStatusLine().getStatusCode() == 200) {
                try {
                    result = EntityUtils.toString(response.getEntity());
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        } catch (IOException e) {
           e.printStackTrace();
        }
        if(result !=null){
            return result;
        }else{
            return "";
        }
    }
    
    private static byte[] getContent(HttpResponse response)
            throws IOException {
        InputStream result = null;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        try {
            HttpEntity resEntity = response.getEntity();
            if (resEntity != null) {
                result = resEntity.getContent();
                int len = 0;
                while ((len = result.read()) != -1) {
                    out.write(len);
                }
                return out.toByteArray();
            }
        } catch (IOException e) {
            e.printStackTrace();
            throw new IOException("getContent异常", e);
        } finally {
            out.close();
            if (result != null) {
                result.close();
            }
        }
        return null;
    }

以上为java中http的get与post请求方式，httpPost(String httpUrl,byte[] imagebyte)这个方法可以传递图片等非结构化数据,以流的形式传递。