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Android OkHttp解析

2019-11-08 00:37:52
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okhttp的简单使用,主要包含:一般的get请求一般的post请求基于Http的文件上传文件下载加载图片支持请求回调,直接返回对象、对象集合支持session的保持

1.Http Get

//创建okHttpClient对象OkHttpClient mOkHttpClient = new OkHttpClient();//创建一个Requestfinal Request request = new Request.Builder()                .url("https://github.com/hongyangAndroid")                .build();//new callCall call = mOkHttpClient.newCall(request); //请求加入调度call.enqueue(new Callback()        {            @Override            public void onFailure(Request request, IOException e)            {            }            @Override            public void onResponse(final Response response) throws IOException            {                    //String htmlStr =  response.body().string();            }        });                     (1)以上就是发送一个get请求的步骤,首先构造一个Request对象,参数最起码有个url,当然你可以通过Request.Builder设置更多的参数比如:headermethod等。     (2)然后通过request的对象去构造得到一个Call对象,类似于将你的请求封装成了任务,既然是任务,就会有execute()cancel()等方法。     (3)最后,我们希望以异步的方式去执行请求,所以我们调用的是call.enqueue,将call加入调度队列,然后等待任务执行完成,我们在Callback中即可得到结果。

看到这,你会发现,整体的写法还是比较长的,所以封装肯定是要做的,不然每个请求这么写,得累死。

ok,需要注意几点:

onResponse回调的参数是response,一般情况下,比如我们希望获得返回的字符串,可以通过response.body().string()获取;如果希望获得返回的二进制字节数组,则调用response.body().bytes();如果你想拿到返回的inputStream,则调用response.body().byteStream()

看到这,你可能会奇怪,竟然还能拿到返回的inputStream,看到这个最起码能意识到一点,这里支持大文件下载,有inputStream我们就可以通过IO的方式写文件。不过也说明一个问题,这个onResponse执行的线程并不是UI线程。的确是的,如果你希望操作控件,还是需要使用handler等,例如:

@Overridepublic void onResponse(final Response response) throws IOException{      final String res = response.body().string();      runOnUiThread(new Runnable()      {          @Override          public void run()          {            mTv.setText(res);          }      });}我们这里是异步的方式去执行,当然也支持阻塞的方式,上面我们也说了Call有一个execute()方法,你也可以直接调用call.execute()通过返回一个Response

2.Http Post 携带参数

post携带参数,也仅仅是Request的构造的不同。

Request request = buildMultipartFormRequest(        url, new File[]{file}, new String[]{fileKey}, null);FormEncodingBuilder builder = new FormEncodingBuilder();   builder.add("username","张鸿洋");Request request = new Request.Builder()                   .url(url)                .post(builder.build())                .build(); mOkHttpClient.newCall(request).enqueue(new Callback(){});大家都清楚,post的时候,参数是包含在请求体中的;所以我们通过FormEncodingBuilder。添加多个String键值对,然后去构造RequestBody,最后完成我们Request的构造。

3.基于Http的文件上传

接下来我们在介绍一个可以构造RequestBody的Builder,叫做MultipartBuilder。当我们需要做类似于表单上传的时候,就可以使用它来构造我们的requestBody。

File file = new File(Environment.getExternalStorageDirectory(), "balabala.mp4");RequestBody fileBody = RequestBody.create(MediaType.parse("application/octet-stream"), file);RequestBody requestBody = new MultipartBuilder()     .type(MultipartBuilder.FORM)     .addPart(Headers.of(          "Content-Disposition",               "form-data; name=/"username/""),           RequestBody.create(null, "wind"))     .addPart(Headers.of(         "Content-Disposition",          "form-data; name=/"mFile/";          filename=/"wjd.mp4/""), fileBody)     .build();Request request = new Request.Builder()    .url("http://192.168.1.103:8080/okHttpServer/fileUpload")    .post(requestBody)    .build();Call call = mOkHttpClient.newCall(request);call.enqueue(new Callback(){    //...});我们通过MultipartBuilder的addPart方法可以添加键值对或者文件。

对于我们最开始的目录还剩下图片下载,文件下载;这两个一个是通过回调的Response拿到byte[]然后decode成图片;文件下载,就是拿到inputStream做写文件操作,我们这里就不赘述了。

4.封装

4.1 get请求

 OkHttpClientManager.getAsyn("https://www.baidu.com", new OkHttpClientManager.ResultCallback<String>()        {            @Override            public void onError(Request request, Exception e)            {                e.PRintStackTrace();            }            @Override            public void onResponse(String u)            {                mTv.setText(u);//注意这里是UI线程            }        });对于一般的请求,我们希望给个url,然后CallBack里面直接操作控件。

4.2 文件上传且携带参数

我们希望提供一个方法,传入url,params,file,callback即可。

OkHttpClientManager.postAsyn("http://192.168.1.103:8080/okHttpServer/fileUpload",//    new OkHttpClientManager.ResultCallback<String>()    {        @Override        public void onError(Request request, IOException e)        {            e.printStackTrace();        }        @Override        public void onResponse(String result)        {        }    },//    file,//    "mFile",//    new OkHttpClientManager.Param[]{            new OkHttpClientManager.Param("username", "zhy"),            new OkHttpClientManager.Param("passWord", "123")}        );

键值对没什么说的,参数3为file,参数4为file对应的name,这个name不是文件的名字; 对应于http中的

<input type="file" name="mFile" >

对应的是name后面的值,即mFile.

4.3 文件下载

对于文件下载,提供url,目标dir,callback即可。

OkHttpClientManager.downloadAsyn(    "http://192.168.1.103:8080/okHttpServer/files/messenger_01.png",        Environment.getExternalStorageDirectory().getAbsolutePath(), new OkHttpClientManager.ResultCallback<String>()    {        @Override        public void onError(Request request, IOException e)        {        }        @Override        public void onResponse(String response)        {            //文件下载成功,这里回调的reponse为文件的absolutePath        }});4.4 展示图片

展示图片,我们希望提供一个url和一个imageview,如果下载成功,直接帮我们设置上即可。

OkHttpClientManager.displayImage(mImageView,      "http://images.csdn.net/20150817/1.jpg");4.5 返回对象或者对象列表,整合json

例如现在有个User实体类:

public class User {    public String username ;     public String password  ;    public User() {        // TODO Auto-generated constructor stub    }    public User(String username, String password) {        this.username = username;        this.password = password;    }    @Override    public String toString()    {        return "User{" +                "username='" + username + '/'' +                ", password='" + password + '/'' +                '}';    }}服务端返回:

{"username":"zhy","password":"123"}客户端可以如下方式调用:

 OkHttpClientManager.getAsyn("http://192.168.56.1:8080/okHttpServer/user!getUser",new OkHttpClientManager.ResultCallback<User>(){    @Override    public void onError(Request request, Exception e)    {        e.printStackTrace();    }    @Override    public void onResponse(User user)    {        mTv.setText(u.toString());//UI线程    }});我们传入泛型User,在onResponse里面直接回调User对象。 这里特别要注意的事,如果在json字符串->实体对象过程中发生错误,程序不会崩溃,onError方法会被回调。

(2)回调对象集合

依然是上述的User类,服务端返回

[{"username":"zhy","password":"123"},{"username":"lmj","password":"12345"}]则客户端可以如下调用:

OkHttpClientManager.getAsyn("http://192.168.56.1:8080/okHttpServer/user!getUsers",new OkHttpClientManager.ResultCallback<List<User>>(){    @Override    public void onError(Request request, Exception e)    {        e.printStackTrace();    }    @Override    public void onResponse(List<User> us)    {        Log.e("TAG", us.size() + "");        mTv.setText(us.get(1).toString());    }});完整的封装类如下:

package com.zhy.utils.http.okhttp;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.os.Handler;import android.os.Looper;import android.widget.ImageView;import com.google.gson.Gson;import com.google.gson.internal.$Gson$Types;import com.squareup.okhttp.Call;import com.squareup.okhttp.Callback;import com.squareup.okhttp.FormEncodingBuilder;import com.squareup.okhttp.Headers;import com.squareup.okhttp.MediaType;import com.squareup.okhttp.MultipartBuilder;import com.squareup.okhttp.OkHttpClient;import com.squareup.okhttp.Request;import com.squareup.okhttp.RequestBody;import com.squareup.okhttp.Response;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.lang.reflect.ParameterizedType;import java.lang.reflect.Type;import java.net.CookieManager;import java.net.CookiePolicy;import java.net.FileNameMap;import java.net.URLConnection;import java.util.HashMap;import java.util.Map;import java.util.Set;/** * Created by zhy on 15/8/17. */public class OkHttpClientManager{    private static OkHttpClientManager mInstance;    private OkHttpClient mOkHttpClient;    private Handler mDelivery;    private Gson mGson;    private static final String TAG = "OkHttpClientManager";    private OkHttpClientManager()    {        mOkHttpClient = new OkHttpClient();        //cookie enabled        mOkHttpClient.setCookieHandler(new CookieManager(null, CookiePolicy.ACCEPT_ORIGINAL_SERVER));        mDelivery = new Handler(Looper.getMainLooper());        mGson = new Gson();    }    public static OkHttpClientManager getInstance()    {        if (mInstance == null)        {            synchronized (OkHttpClientManager.class)            {                if (mInstance == null)                {                    mInstance = new OkHttpClientManager();                }            }        }        return mInstance;    }    /**     * 同步的Get请求     *     * @param url     * @return Response     */    private Response _getAsyn(String url) throws IOException    {        final Request request = new Request.Builder()                .url(url)                .build();        Call call = mOkHttpClient.newCall(request);        Response execute = call.execute();        return execute;    }    /**     * 同步的Get请求     *     * @param url     * @return 字符串     */    private String _getAsString(String url) throws IOException    {        Response execute = _getAsyn(url);        return execute.body().string();    }    /**     * 异步的get请求     *     * @param url     * @param callback     */    private void _getAsyn(String url, final ResultCallback callback)    {        final Request request = new Request.Builder()                .url(url)                .build();        deliveryResult(callback, request);    }    /**     * 同步的Post请求     *     * @param url     * @param params post的参数     * @return     */    private Response _post(String url, Param... params) throws IOException    {        Request request = buildPostRequest(url, params);        Response response = mOkHttpClient.newCall(request).execute();        return response;    }    /**     * 同步的Post请求     *     * @param url     * @param params post的参数     * @return 字符串     */    private String _postAsString(String url, Param... params) throws IOException    {        Response response = _post(url, params);        return response.body().string();    }    /**     * 异步的post请求     *     * @param url     * @param callback     * @param params     */    private void _postAsyn(String url, final ResultCallback callback, Param... params)    {        Request request = buildPostRequest(url, params);        deliveryResult(callback, request);    }    /**     * 异步的post请求     *     * @param url     * @param callback     * @param params     */    private void _postAsyn(String url, final ResultCallback callback, Map<String, String> params)    {        Param[] paramsArr = map2Params(params);        Request request = buildPostRequest(url, paramsArr);        deliveryResult(callback, request);    }    /**     * 同步基于post的文件上传     *     * @param params     * @return     */    private Response _post(String url, File[] files, String[] fileKeys, Param... params) throws IOException    {        Request request = buildMultipartFormRequest(url, files, fileKeys, params);        return mOkHttpClient.newCall(request).execute();    }    private Response _post(String url, File file, String fileKey) throws IOException    {        Request request = buildMultipartFormRequest(url, new File[]{file}, new String[]{fileKey}, null);        return mOkHttpClient.newCall(request).execute();    }    private Response _post(String url, File file, String fileKey, Param... params) throws IOException    {        Request request = buildMultipartFormRequest(url, new File[]{file}, new String[]{fileKey}, params);        return mOkHttpClient.newCall(request).execute();    }    /**     * 异步基于post的文件上传     *     * @param url     * @param callback     * @param files     * @param fileKeys     * @throws IOException     */    private void _postAsyn(String url, ResultCallback callback, File[] files, String[] fileKeys, Param... params) throws IOException    {        Request request = buildMultipartFormRequest(url, files, fileKeys, params);        deliveryResult(callback, request);    }    /**     * 异步基于post的文件上传,单文件不带参数上传     *     * @param url     * @param callback     * @param file     * @param fileKey     * @throws IOException     */    private void _postAsyn(String url, ResultCallback callback, File file, String fileKey) throws IOException    {        Request request = buildMultipartFormRequest(url, new File[]{file}, new String[]{fileKey}, null);        deliveryResult(callback, request);    }    /**     * 异步基于post的文件上传,单文件且携带其他form参数上传     *     * @param url     * @param callback     * @param file     * @param fileKey     * @param params     * @throws IOException     */    private void _postAsyn(String url, ResultCallback callback, File file, String fileKey, Param... params) throws IOException    {        Request request = buildMultipartFormRequest(url, new File[]{file}, new String[]{fileKey}, params);        deliveryResult(callback, request);    }    /**     * 异步下载文件     *     * @param url     * @param destFileDir 本地文件存储的文件夹     * @param callback     */    private void _downloadAsyn(final String url, final String destFileDir, final ResultCallback callback)    {        final Request request = new Request.Builder()                .url(url)                .build();        final Call call = mOkHttpClient.newCall(request);        call.enqueue(new Callback()        {            @Override            public void onFailure(final Request request, final IOException e)            {                sendFailedStringCallback(request, e, callback);            }            @Override            public void onResponse(Response response)            {                InputStream is = null;                byte[] buf = new byte[2048];                int len = 0;                FileOutputStream fos = null;                try                {                    is = response.body().byteStream();                    File file = new File(destFileDir, getFileName(url));                    fos = new FileOutputStream(file);                    while ((len = is.read(buf)) != -1)                    {                        fos.write(buf, 0, len);                    }                    fos.flush();                    //如果下载文件成功,第一个参数为文件的绝对路径                    sendSuccessResultCallback(file.getAbsolutePath(), callback);                } catch (IOException e)                {                    sendFailedStringCallback(response.request(), e, callback);                } finally                {                    try                    {                        if (is != null) is.close();                    } catch (IOException e)                    {                    }                    try                    {                        if (fos != null) fos.close();                    } catch (IOException e)                    {                    }                }            }        });    }    private String getFileName(String path)    {        int separatorIndex = path.lastIndexOf("/");        return (separatorIndex < 0) ? path : path.substring(separatorIndex + 1, path.length());    }    /**     * 加载图片     *     * @param view     * @param url     * @throws IOException     */    private void _displayImage(final ImageView view, final String url, final int errorResId)    {        final Request request = new Request.Builder()                .url(url)                .build();        Call call = mOkHttpClient.newCall(request);        call.enqueue(new Callback()        {            @Override            public void onFailure(Request request, IOException e)            {                setErrorResId(view, errorResId);            }            @Override            public void onResponse(Response response)            {                InputStream is = null;                try                {                    is = response.body().byteStream();                    ImageUtils.ImageSize actualImageSize = ImageUtils.getImageSize(is);                    ImageUtils.ImageSize imageViewSize = ImageUtils.getImageViewSize(view);                    int inSampleSize = ImageUtils.calculateInSampleSize(actualImageSize, imageViewSize);                    try                    {                        is.reset();                    } catch (IOException e)                    {                        response = _getAsyn(url);                        is = response.body().byteStream();                    }                    BitmapFactory.Options ops = new BitmapFactory.Options();                    ops.inJustDecodeBounds = false;                    ops.inSampleSize = inSampleSize;                    final Bitmap bm = BitmapFactory.decodeStream(is, null, ops);                    mDelivery.post(new Runnable()                    {                        @Override                        public void run()                        {                            view.setImageBitmap(bm);                        }                    });                } catch (Exception e)                {                    setErrorResId(view, errorResId);                } finally                {                    if (is != null) try                    {                        is.close();                    } catch (IOException e)                    {                        e.printStackTrace();                    }                }            }        });    }    private void setErrorResId(final ImageView view, final int errorResId)    {        mDelivery.post(new Runnable()        {            @Override            public void run()            {                view.setImageResource(errorResId);            }        });    }    //*************对外公布的方法************    public static Response getAsyn(String url) throws IOException    {        return getInstance()._getAsyn(url);    }    public static String getAsString(String url) throws IOException    {        return getInstance()._getAsString(url);    }    public static void getAsyn(String url, ResultCallback callback)    {        getInstance()._getAsyn(url, callback);    }    public static Response post(String url, Param... params) throws IOException    {        return getInstance()._post(url, params);    }    public static String postAsString(String url, Param... params) throws IOException    {        return getInstance()._postAsString(url, params);    }    public static void postAsyn(String url, final ResultCallback callback, Param... params)    {        getInstance()._postAsyn(url, callback, params);    }    public static void postAsyn(String url, final ResultCallback callback, Map<String, String> params)    {        getInstance()._postAsyn(url, callback, params);    }    public static Response post(String url, File[] files, String[] fileKeys, Param... params) throws IOException    {        return getInstance()._post(url, files, fileKeys, params);    }    public static Response post(String url, File file, String fileKey) throws IOException    {        return getInstance()._post(url, file, fileKey);    }    public static Response post(String url, File file, String fileKey, Param... params) throws IOException    {        return getInstance()._post(url, file, fileKey, params);    }    public static void postAsyn(String url, ResultCallback callback, File[] files, String[] fileKeys, Param... params) throws IOException    {        getInstance()._postAsyn(url, callback, files, fileKeys, params);    }    public static void postAsyn(String url, ResultCallback callback, File file, String fileKey) throws IOException    {        getInstance()._postAsyn(url, callback, file, fileKey);    }    public static void postAsyn(String url, ResultCallback callback, File file, String fileKey, Param... params) throws IOException    {        getInstance()._postAsyn(url, callback, file, fileKey, params);    }    public static void displayImage(final ImageView view, String url, int errorResId) throws IOException    {        getInstance()._displayImage(view, url, errorResId);    }    public static void displayImage(final ImageView view, String url)    {        getInstance()._displayImage(view, url, -1);    }    public static void downloadAsyn(String url, String destDir, ResultCallback callback)    {        getInstance()._downloadAsyn(url, destDir, callback);    }    //****************************    private Request buildMultipartFormRequest(String url, File[] files,                                              String[] fileKeys, Param[] params)    {        params = validateParam(params);        MultipartBuilder builder = new MultipartBuilder()                .type(MultipartBuilder.FORM);        for (Param param : params)        {            builder.addPart(Headers.of("Content-Disposition", "form-data; name=/"" + param.key + "/""),                    RequestBody.create(null, param.value));        }        if (files != null)        {            RequestBody fileBody = null;            for (int i = 0; i < files.length; i++)            {                File file = files[i];                String fileName = file.getName();                fileBody = RequestBody.create(MediaType.parse(guessMimeType(fileName)), file);                //TODO 根据文件名设置contentType                builder.addPart(Headers.of("Content-Disposition",                                "form-data; name=/"" + fileKeys[i] + "/"; filename=/"" + fileName + "/""),                        fileBody);            }        }        RequestBody requestBody = builder.build();        return new Request.Builder()                .url(url)                .post(requestBody)                .build();    }    private String guessMimeType(String path)    {        FileNameMap fileNameMap = URLConnection.getFileNameMap();        String contentTypeFor = fileNameMap.getContentTypeFor(path);        if (contentTypeFor == null)        {            contentTypeFor = "application/octet-stream";        }        return contentTypeFor;    }    private Param[] validateParam(Param[] params)    {        if (params == null)            return new Param[0];        else return params;    }    private Param[] map2Params(Map<String, String> params)    {        if (params == null) return new Param[0];        int size = params.size();        Param[] res = new Param[size];        Set<Map.Entry<String, String>> entries = params.entrySet();        int i = 0;        for (Map.Entry<String, String> entry : entries)        {            res[i++] = new Param(entry.getKey(), entry.getValue());        }        return res;    }    private static final String SESSION_KEY = "Set-Cookie";    private static final String mSessionKey = "JSESSIONID";    private Map<String, String> mSessions = new HashMap<String, String>();    private void deliveryResult(final ResultCallback callback, Request request)    {        mOkHttpClient.newCall(request).enqueue(new Callback()        {            @Override            public void onFailure(final Request request, final IOException e)            {                sendFailedStringCallback(request, e, callback);            }            @Override            public void onResponse(final Response response)            {                try                {                    final String string = response.body().string();                    if (callback.mType == String.class)                    {                        sendSuccessResultCallback(string, callback);                    } else                    {                        Object o = mGson.fromJson(string, callback.mType);                        sendSuccessResultCallback(o, callback);                    }                } catch (IOException e)                {                    sendFailedStringCallback(response.request(), e, callback);                } catch (com.google.gson.JsonParseException e)//Json解析的错误                {                    sendFailedStringCallback(response.request(), e, callback);                }            }        });    }    private void sendFailedStringCallback(final Request request, final Exception e, final ResultCallback callback)    {        mDelivery.post(new Runnable()        {            @Override            public void run()            {                if (callback != null)                    callback.onError(request, e);            }        });    }    private void sendSuccessResultCallback(final Object object, final ResultCallback callback)    {        mDelivery.post(new Runnable()        {            @Override            public void run()            {                if (callback != null)                {                    callback.onResponse(object);                }            }        });    }    private Request buildPostRequest(String url, Param[] params)    {        if (params == null)        {            params = new Param[0];        }        FormEncodingBuilder builder = new FormEncodingBuilder();        for (Param param : params)        {            builder.add(param.key, param.value);        }        RequestBody requestBody = builder.build();        return new Request.Builder()                .url(url)                .post(requestBody)                .build();    }    public static abstract class ResultCallback<T>    {        Type mType;        public ResultCallback()        {            mType = getSuperclassTypeParameter(getClass());        }        static Type getSuperclassTypeParameter(Class<?> subclass)        {            Type superclass = subclass.getGenericSuperclass();            if (superclass instanceof Class)            {                throw new RuntimeException("Missing type parameter.");            }            ParameterizedType parameterized = (ParameterizedType) superclass;            return $Gson$Types.canonicalize(parameterized.getActualTypeArguments()[0]);        }        public abstract void onError(Request request, Exception e);        public abstract void onResponse(T response);    }    public static class Param    {        public Param()        {        }        public Param(String key, String value)        {            this.key = key;            this.value = value;        }        String key;        String value;    }}


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