Android OkHttp完全解析 是时候来了解OkHttp了，程序员面试防坑宝典

{

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.

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()

{

@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. 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,

"images.csdn.net/20150817/1.…");

内部会自动根据imageview的大小自动对图片进行合适的压缩。虽然，这里可能不适合一次性加载大量图片的场景，但是对于app中偶尔有几个图片的加载，还是可用的。

---

四、整合Gson

很多人提出项目中使用时，服务端返回的是Json字符串，希望客户端回调可以直接拿到对象，于是整合进入了Gson，完善该功能。

（一）直接回调对象

例如现在有个User实体类：

package com.zhy.utils.http.okhttp;

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()

{

@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。

注意：这里做了少许的更新，接口命名从StringCallback修改为ResultCallback。接口中的onFailure方法修改为onError。

(二) 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>()

{

@Override

public void onError(Request request, Exception e)

{

e.printStackTrace();

}

@Override

public void onResponse(List us)

{

Log.e("TAG", us.size() + "");

mTv.setText(us.get(1).toString());

}

});

唯一的区别，就是泛型变为List<User> ，ok ， 如果发现bug或者有任何意见欢迎留言。

---

源码

ok，基本介绍完了，对于封装的代码其实也很简单，我就直接贴出来了，因为也没什么好介绍的，如果你看完上面的用法，肯定可以看懂：

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);

}

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