Android OKHttp
OkHttp 会从很多常用的连接问题中自动恢复。如果您的服务器配置了多个IP地址,当第一个IP连接失败的时候,OkHttp会自动尝试下一个IP。OkHttp还处理了代理服务器问题和SSL握手失败问题。使用 OkHttp 无需重写您程序中的网络代码。OkHttp实现了几乎和java.net.HttpURLConnection一样的API。如果你用了 Apache HttpClient,则OkHttp也提供了一个对应的okhttp-apache 模块。
Android Studio 配置gradle:
compile 'com.squareup.okhttp3:okhttp:3.2.0'
compile 'com.squareup.okio:okio:1.7.0'
添加网络权限:
<uses-permissionandroid:name="android.permission.INTERNET"/>
异步GET请求:
private void getAsynHttp() {
mOkHttpClient=new OkHttpClient();
Request.Builder requestBuilder = new Request.Builder().url("http://www.baidu.com");
//可以省略,默认是GET请求
requestBuilder.method("GET",null);
Request request = requestBuilder.build();
Call mcall= mOkHttpClient.newCall(request);
mcall.enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
}
@Override
public void onResponse(Call call, Response response) throws IOException {
if (null != response.cacheResponse()) {
String str = response.cacheResponse().toString();
Log.i("wangshu", "cache---" + str);
} else {
response.body().string();
String str = response.networkResponse().toString();
Log.i("wangshu", "network---" + str);
}
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(), "请求成功", Toast.LENGTH_SHORT).show();
}
});
}
});
}
同步get请求:
private String getSyncHttp() throws IOException{
OkHttpClient mOkHttpClient = new OkHttpClient();
//创建请求Request
final Request request = new Request.Builder()
.url("http://www.baidu.com")
.build();
Call call = mOkHttpClient.newCall(request);
Response mResponse=call.execute();
if (mResponse.isSuccessful()) {
return mResponse.body().string();
} else {
throw new IOException("Unexpected code " + mResponse);
}
}
异步POST请求:post与get不同的就是要要创建RequestBody并传进Request中,同样onResponse回调不是在UI线程。OkHttp3异步POST请求和OkHttp2.x有一些差别就是没有FormEncodingBuilder这个类,替代它的是功能更加强大的FormBody:
private void postAsynHttp() {
mOkHttpClient=new OkHttpClient();
RequestBody formBody = new FormBody.Builder()
.add("size", "10")
.build();
Request request = new Request.Builder()
.url("http://api.1-blog.com/biz/bizserver/article/list.do")
.post(formBody)
.build();
Call call = mOkHttpClient.newCall(request);
call.enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
}
@Override
public void onResponse(Call call, Response response) throws IOException {
String str = response.body().string();
Log.i("wangshu", str);
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(), "请求成功", Toast.LENGTH_SHORT).show();
}
});
}
});
}
异步上传文件:
private void postAsynFile() {
mOkHttpClient=new OkHttpClient();
File file = new File("/sdcard/wangshu.txt");
Request request = new Request.Builder()
.url("https://api.github.com/markdown/raw")
.post(RequestBody.create(MEDIA_TYPE_MARKDOWN, file))
.build();
mOkHttpClient.newCall(request).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
}
@Override
public void onResponse(Call call, Response response) throws IOException {
Log.i("wangshu",response.body().string());
}
});
}
设置超时时间和缓存:和OkHttp2.x有区别的是不能通过OkHttpClient直接设置超时时间和缓存了,而是通过OkHttpClient.Builder来设置,通过builder配置好OkHttpClient后用builder.build()来返回OkHttpClient,所以我们通常不会调用new OkHttpClient()来得到OkHttpClient,而是通过builder.build():
File sdcache = getExternalCacheDir();
int cacheSize = 10 * 1024 * 1024;
OkHttpClient.Builder builder = new OkHttpClient.Builder()
.connectTimeout(15, TimeUnit.SECONDS)
.writeTimeout(20, TimeUnit.SECONDS)
.readTimeout(20, TimeUnit.SECONDS)
.cache(new Cache(sdcache.getAbsoluteFile(), cacheSize));
OkHttpClient mOkHttpClient=builder.build();
取消请求:
使用call.cancel()可以立即停止掉一个正在执行的call。如果一个线程正在写请求或者读响应,将会引发IOException。当用户离开一个应用时或者跳到其他界面时,使用Call.cancel()可以节约网络资源,另外不管同步还是异步的call都可以取消。 也可以通过tags来同时取消多个请求。当你构建一请求时,使用RequestBuilder.tag(tag)来分配一个标签。之后你就可以用OkHttpClient.cancel(tag)来取消所有带有这个tag的call。
private void cancel(){
final Request request = new Request.Builder()
.url("http://www.baidu.com")
.cacheControl(CacheControl.FORCE_NETWORK)
.build();
Call call=null;
call = mOkHttpClient.newCall(request);
final Call finalCall = call;
//100毫秒后取消call
executor.schedule(new Runnable() {
@Override public void run() {
finalCall.cancel();
}
}, 100, TimeUnit.MILLISECONDS);
call.enqueue(new Callback() {
@Override
public void onFailure(Request request, IOException e) {
}
@Override
public void onResponse(final Response response) {
if (null != response.cacheResponse()) {
String str = response.cacheResponse().toString();
Log.i("wangshu", "cache---" + str);
} else {
try {
response.body().string();
} catch (IOException e) {
Log.i("wangshu", "IOException");
e.printStackTrace();
}
String str = response.networkResponse().toString();
Log.i("wangshu", "network---" + str);
}
}
});
Log.i("wangshu", "是否取消成功"+call.isCanceled());
}