okhttp可以用于电脑客户端吗（Okhttp的使用记录）

第一步，添加依赖库'com.squareup.okhttp3:okhttp:3.10.0'

自动下载两个库,OkHttp和Okio,后者是前者的通信基础

第二步,具体用法

创建OkHttpClient实例

实现一个默认的客户端,没有连接时间限制

OkHttpClient client=new OkHttpClient();

实现一个对连接时间读取时间有限制的客户端,超过时间限制,强制失败

OkHttpClient client=new OkHttpClient.builder().connectTimeout(8000, TimeUnit.MILLISECONDS).readTimeout(8000,TimeUnit.MILLISECONDS).build();

发起Http请求(GET)

有同步和异步两种

同步需要自己开一个线程,执行网络连接

创建request请求,并在build()方法前连缀属性;

调用client的newCall()方法创建Call对象;

调用Call对象的excute()方法获取服务器返回的数据response;

返回结果数据格式依赖服务器实现

2. new Thread(new Runnable() {
3. @Override
4. public void run() {
5. OkHttpClient client=new OkHttpClient.Builder().connectTimeout(8000, TimeUnit.MILLISECONDS).readTimeout(8000,TimeUnit.MILLISECONDS).build();
6. Request request= new Request.Builder().url(address).build();
7. try {
8. Response response=client.newCall(request).execute();
9. if (response.body() != null) {
10. String strResponse = response.body().string();
11. }
12. } catch (IOException e) {
13. e.printStackTrace();
14. }
15. }
16. }).start();

异步get请求,因为onResponse和onFailure()默认开启子线程,需要更新UI时,需要跳转主UI线程

2. OkHttpClient client=new OkHttpClient.Builder().connectTimeout(8000, TimeUnit.MILLISECONDS).readTimeout(8000,TimeUnit.MILLISECONDS).build();
3. Request request= new Request.Builder().url(address).build();
4. client.newCall(request).enqueue(new callback() {
5. @Override
6. public void onFailure(Call call, IOException e) {
7. // do something
8. Log.d("http connect","失败");
9. Log.d("http connect","e" e.toString());
10. }
12. @Override
13. public void onResponse(Call call, Response response) throws IOException {
15. if (response.isSuccessful()){
16. // do something
17. Log.d("http connect","获取数据");
18. Log.d("http connect","response.code()==" response.code());
19. Log.d("http connect","response.body().string()==" response.body().string());
20. }
21. }
22. });

发起POST请求

创建RequestBody对象来存放待提交数据;

新建request请求,在build()前调用post()方法,并把body对象传入;

后续操作与get并没有区别

2. OkHttpClient client=new OkHttpClient.Builder().connectTimeout(8000, TimeUnit.MILLISECONDS).readTimeout(8000,TimeUnit.MILLISECONDS).build();
3. RequestBody body=new FormBody.Builder().add("account",account).add("password",password).build();
4. Request request= new Request.Builder().url(address).post(body).build();
5. client.newCall(request).enqueue(new Callback() {
6. @Override
7. public void onFailure(Call call, IOException e) {
8. // do something
9. Log.d("http connect","失败");
10. Log.d("http connect","e" e.toString());
11. }
13. @Override
14. public void onResponse(Call call, Response response) throws IOException {
16. if (response.isSuccessful()){
17. // do something
18. Log.d("http connect","获取数据");
19. Log.d("http connect","response.code()==" response.code());
20. Log.d("http connect","response.body().string()==" response.body().string());
21. }
22. }
23. });

response.code(),这个是http协议自带的,200表示连接成功

response.body().string()要放在子线程,且只执行一次

做一个小小的封装

2. public class OkHttpUtils {
3. private static OkHttpClient client ;
4. private static final String TAG = "OkHttpUtils";
5. private static ConcurrentHashMap<String, List<Cookie>> cookiestore = new ConcurrentHashMap<>();
8. //单例模式返回一个实例
9. public static OkHttpClient getInstance(){
10. if (client==null)
11. synchronized (OkHttpClient.class){
13. if (client==null){
15. //添加cookieJar,自动化管理cookie,获得一致的sessions值
16. //添加连接超时和读取超时,在网络状况不好的时候可以做出提示.
17. client=new OkHttpClient.Builder().cookieJar(new CookieJar() {
18. @Override
19. public void saveFromResponse(HttpUrl url, List<Cookie> cookies) {
20. Log.i(TAG, "saveFromResponse: cookies=" cookies);
21. Log.i(TAG, "saveFromResponse: cookieStore=" cookieStore.size());
23. cookieStore.put(url.host(), cookies);
24. }
26. @Override
27. public List<Cookie> loadForRequest(HttpUrl url) {
29. List<Cookie> cookies = cookieStore.get(url.host());
31. Log.i(TAG, "loadForRequest: cookies=" cookies);
33. return cookies != null ? cookies : new ArrayList<Cookie>();
34. }
35. }).connectTimeout(8000, TimeUnit.MILLISECONDS).readTimeout(8000,TimeUnit.MILLISECONDS).build();
36. }
37. }
38. return client;
39. }
41. //封装了一个静态方法.用来实现登录,url是你要访问的网址或者接口.在使用时可以通过匿名类,根据实际情况实现一个callback,在callback方法中,分别对成功和失败做处理
42. public static void sendHttpLoginRequest( String account, String password, Callback callback) {
43. OkHttpClient client=OkHttpUtils.getInstance();
44. RequestBody body=new FormBody.Builder().add("account",account).add("password",password).build();
45. Request request= new Request.Builder().url("url").post(body).build();
46. client.newCall(request).enqueue(callback);
47. }
49. }

下面实际使用下,demo,点击获取按钮,会把获取到的信息设置到TextView中

2. public class Main2Activity extends AppCompatActivity implements View.OnClickListener{
4. private TextView mContent;
5. private Button bInsquire;
6. private Button bInfor;
7. private Button bModifyPhone;
8. private static final String TAG = "Main2Activity";
10. //定义常量
11. public static final int GET_CONTACT=1;
12. public static final int GET_INFOR=2;
13. public static final int MODIFY_PHONE=3;
16. //定义一个内部Handler,用来获取callback发送的消息,重写内部方法,并处理消息
17. private Handler handler=new Handler(){
18. @Override
19. public void handleMessage(Message msg) {
20. if (msg!=null){
21. switch (msg.what){
22. case GET_CONTACT:
23. mContent.setText((String)msg.obj);
24. case GET_INFOR:
25. mContent.setText((String)msg.obj);
26. case MODIFY_PHONE:
27. mContent.setText((String)msg.obj);
28. }
29. }else{
30. Log.i(TAG, "hanlderNews: msg null");
31. }
32. }
33. });
36. @Override
37. protected void onCreate(Bundle savedInstanceState) {
38. super.onCreate(savedInstanceState);
39. setContentView(R.layout.activity_main2);
41. mContent=findViewById(R.id.tv_content);
42. bInsquire=findViewById(R.id.b_inquire_contacts);
43. bInfor=findViewById(R.id.b_Information);
44. bModifyPhone=findViewById(R.id.b_modify_phone);
46. bInsquire.setOnClickListener(this);
47. bInfor.setOnClickListener(this);
48. bModifyPhone.setOnClickListener(this);
49. }
51. @Override
52. public void onClick(View view) {
53. switch (view.getId()){
54. case R.id.b_inquire_contacts:
55. Log.i(TAG, "onClick: bInsquire");
56. //匿名类,重写了失败和成功的处理,成功的时候,给Handler发送消息,消息内容为获得的相应体Response的内容
57. OkHttpUtils.sendHttpContactsRequest(new Callback() {
58. @Override
59. public void onFailure(Call call, IOException e) {
60. Log.i(TAG, "onFailure: connect failed");
61. }
63. @Override
64. public void onResponse(Call call, Response response) throws IOException {
65. if (response!=null){
66. String strResponse=response.body().string();
67. Log.d("http connect","response.code()==" response.code());
68. Log.d("http connect","response.body().toString()==" strResponse);
70. Message msg=Message.obtain();
71. msg.what=GET_CONTACT;
72. msg.obj=strResponse;
73. mHanlderUtils.sendMessage(msg);
74. }else {
75. Log.i(TAG, "onResponse: response failed");
76. }
77. }
78. });
79. break;
80. case R.id.b_Information:
82. case R.id.b_modify_phone:
84. }
85. }
86. }

注意,在新建Handler的时候,AS3.0版本以后会出现告警信息

This Handler class should be static or leaks might occur (anonymous android.os.Handler)

这是由于handler获取到activity的引用,可能由于消息处理的不及时,延时任务会导致activity不能被成功finish(),出现内存泄漏的风险,这里参考 https://blog.csdn.net/banxiali/article/details/51494842

对hanlder进行封装,持有当前活动的弱引用,由于封装的hanlder会处理不同的message,所以在封装Handler的handlerMessage()方法中回调接口方法,在不同的活动里根据情况实现这个接口即可

接口方法

2. public interface HandlerNewsInterface {
3. void hanlderNews(Message msg);
4. }

封装handler

2. public class HandlerUtils extends Handler {
4. private WeakReference<Activity> mActivityReference;
5. private HandlerNewsInterface mHanlderNews;
7. HandlerUtils(Activity mActivity,HandlerNewsInterface mHanlderNews) {
8. this.mActivityReference = new WeakReference<>(mActivity);
9. this.mHanlderNews=mHanlderNews;
10. }
13. @Override
14. public void handleMessage(Message msg) {
15. mHanlderNews.hanlderNews(msg);
16. super.handleMessage(msg);
17. }
18. }

所以上面的Demo中的Handler就可以这样实现

2. private HandlerUtils mHanlderUtils=new HandlerUtils(this, new HandlerNewsInterface() {
3. @Override
4. public void hanlderNews(Message msg) {
5. if (msg!=null){
6. switch (msg.what){
7. case GET_CONTACT:
8. mContent.setText((String)msg.obj);
9. case GET_INFOR:
10. mContent.setText((String)msg.obj);
11. case MODIFY_PHONE:
12. mContent.setText((String)msg.obj);
13. }
14. }else{
15. Log.i(TAG, "hanlderNews: msg null");
16. }
18. }
19. });

记得要在活动消失前,移除hanlder中添加的消息

2. @Override
3. protected void onDestroy() {
4. mHandlerUtils.removeMessages(GET_CONTACT);
5. mHandlerUtils.removeMessages(GET_INFOR);
6. mHandlerUtils.removeMessages(MODIFY_PHONE);
7. super.onDestroy();
8. }

注意,

A.网络请求,需要在配置文件中声明权限

记得在AndroidManifest.xml中配置网络权限。

<uses-permission android:name="android.permission.INTERNET"></uses-permission>

B.对okhttp进行底层封装

对okHttp的更多用法,参考

https://www.jianshu.com/p/ef9282217d07

1.单例模式,获取客户端实例保证

这个唯一的实例,可以在初始化时就设置连接超时,读取超时和写入超时,cookieJar自动管理cookie,可以设置缓存大小和目录

2 对网络连接超时和读取超时的处理

首先,在设置客户端的时候,我们在build()方法中添加了connectTimOut()和ReadTimeOut()方法,添加了超时属性

接下来,在callBack中返回失败的接口中分情况处理

2. @Override
3. public void onFailure(Call call, IOException e) {
5. // do something
6. Log.d("http connect","失败");
7. //连接失败,一般是没有网络或者服务器问题
8. if (e instanceof ConnectException){
9. Log.d("http connect","ConnectException e=" e.toString());
10. }
11. //超时异常,一般是网络不好,可以设置重连以及重连次数
12. if (e instanceof SocketTimeoutException){
13. Log.d("http connect","SocketTimeoutException e=" e.toString());
14. }
15. }

3 psot数据的类型

表单数据(键值对)

RequestBody body=new FormBody.Builder().add("pwd",pwd).add("newPwd1",new1).add("newPwd2",new2).build();

json数组

2. //设置媒体类型。application/json表示传递的是一个json格式的对象
3. MediaType mediaType = MediaType.parse("application/json");
4. //使用JSONObject封装参数
5. JSONObject jsonObject = new JSONObject();
6. try {
7. jsonObject.put("参数名","参数值");
8. } catch (JSONException e) {
9. e.printStackTrace();
10. }
11. //创建RequestBody对象，将参数按照指定的MediaType封装
12. RequestBody requestBody = RequestBody.create(mediaType,jsonObject.toString());

更多的媒体类型(MediaType)信息 https://baike.baidu.com/item/Internet Media Type?fr=aladdin

图片格式 参考https://blog.csdn.net/zhan10001/article/details/78461143

2. private void sendMessage(String fileName,File file) {
3. RequestBody requestBody = new MultipartBody.Builder()
4. .setType(MultipartBody.FORM)
5. .addFormDataPart("headPic", fileName,
6. RequestBody.create(MediaType.parse("image/jpg"), file))
7. .build();
8. OkHttpClient client=OkHttp3Utils.getInstance();
9. Request request=new Request.Builder().url(DataUtil.ModifyHeadPic).post(requestBody).build();
10. client.newCall(request).enqueue(new Callback() {
11. @Override
12. public void onFailure(Call call, IOException e) {
13. Log.i(TAG, "onFailure: failed");
14. }
16. @Override
17. public void onResponse(Call call, Response response) throws IOException {
19. if (response.isSuccessful()){
20. String result=response.body().string();
21. Log.i(TAG, "onResponse: result=" result);
22. }
23. }
24. });

关于FileName和File的获取

需要知道路径信息imagePath;

2. String fileName=imagePath.substring(imagePath.lastIndexOf("/") 1);
3. File file=new File(imagePath);

表单数据提交能完成大部分的网络请求,毕竟一般发送少,下载多

如果需要发送大量的数据,或者需要接受不同格式的数据,就需要包装成json数组

https://blog.csdn.net/muyi_amen/article/details/58586605

4.添加拦截器

squareup公司自己提供了一个okhttp拦截器方便我们观察网络请求中的数据

使用方法

添加依赖 版本号 与okhttp一致

implementation 'com.squareup.okhttp3:logging-interceptor:3.10.0'

新建一个实例并配置参数

2. HttpLoggingInterceptor logging = new HttpLoggingInterceptor();
3. logging.setLevel(HttpLoggingInterceptor.Level.BODY);

setlevel用来设置日志打印的级别，共包括了四个级别：NONE,BASIC,HEADER,BODY

BASEIC:请求/响应行

HEADER:请求/响应行 头

BODY:请求/响应航 头 体

给okhttp.client添加拦截器

2. client=new OkHttpClient.Builder()
3. .addInterceptor(logging)
4. .build();

5 cookie的持久化

https://www.jianshu.com/p/ef9282217d07

移动端和服务端连接的过程中,为了保证安全,

在okhttp3.0以后,新增了专门的CookieJar类来保存Cookie

2. new CookieJar() {
3. private HashMap<String, List<Cookie>> cookieStore = new HashMap<>();
4. @Override
5. public void saveFromResponse(HttpUrl url, List<Cookie> cookies) {
6. cookieStore.put(url.scheme(), cookies);
8. }
10. @Override
11. public List<Cookie> loadForRequest(HttpUrl url) {
12. List<Cookie> cookies = cookieStore.get(url.scheme());
13. return cookies != null ? cookies : new ArrayList<Cookie>();
14. }
15. }

主要原理:

Url的不变的一部分,比如Url.host()作为key,服务器返回的cookie作为value

saveFromResponse()中建立一个Map,并保存

loadForRequest()中根据url.host()来取出保存的cookie

,