在使用之前,我们需要先在项目中添加OkHttp库的依赖。编辑app/build.gradle文件,在 dependencies闭包添加如下内容:
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:23.4.0'
compile 'com.squareup.okhttp3:okhttp:3.4.1'
}
添加上述依赖会自动下载两个库,一个是OkHttp库,一个是Okio库,后者是前者的通信机础,其中3.4.1是版本号。
OkHttp基本用法,首先创建OkHttpClient的实例,如下所示:
OkHttpClient client = new OkHttpClient();
接下来如果想要发起一条HTTP请求,就需要创建一个Request对象:
Request request = new Request.Builser().build();
当然上述代码只是创建一个空的Request对象,并没有实际作用,我们可以在最终的build()方法之前连缀很多其他的方法来丰富这个Request对象。比如可以通过url()方法来设置目标的网络地址,如下所示:
Request request = new Request.Builser()
.url("http://www.baidu.com")
build();
之后调用OkHttpClient的newCall()方法来创建一个Call对象,并调用它的execute()方法来发送请求并获取服务器返回的数据,写法如下:
Response response = client.newCall(request).execute();
其中Response对象就是服务器返回的数据了,我们可以使用如下写法开得到返回的具体内容:
String responseData = response.body().string();
如果是发起一条POST请求会比GET请求稍微复杂一点,我们需要先构建出一个RequestBody对象来存放待提交的参数,如下所示:
ReqestBody requestBody = new FormBody.Builder()
.add("username","admin")
.add("password","123456")
.build();
然后在Request.Builder中调用一下post()方法,并将RequestBody对象传入:
Request request = new Request.Builder()
.url("http://www.baidu.com")
.post(requestBody)
.build();
接下来就跟GET请求一样了,调用execute()方法来发送请求并获取服务器返回的数据即可。
现在对HTTPURLConnection项目改用Okhttp的方式实现一遍
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<Button
android:id="@+id/send_request"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Send Request"/>
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/response_text"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</ScrollView>
</LinearLayout>
MainActivity.java
package com.example.administrator.httpurlconnection;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import okhttp3.Call;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
TextView responseText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button sendRequest = (Button) findViewById(R.id.send_request);
responseText = (TextView) findViewById(R.id.response_text);
sendRequest.setOnClickListener(this);
}
@Override
public void onClick(View v) {
if (v.getId() == R.id.send_request){
// sendRequestWithHttpURLConnection();//调用 sendRequestWithHttpURLConnection()方法
sendRequestWithOkHttp();
}
}
private void sendRequestWithOkHttp() {
new Thread(new Runnable() {//开启个子线程
@Override
public void run() {
try {
OkHttpClient client = new OkHttpClient();//创建OkHttp实例
Request request = new Request.Builder()//发起一条HTTP请求
.url("http://www.baidu.com")
.build();
//调用OkHttpClient的newCall()方法来创建一个Call对象,并调用它的execute()方法来发送请求并获取服务器返回的数据
Response response = client.newCall(request).execute();
String responseData = response.body().string();
showResponse(responseData);//将服务器的数据返回到界面上
}catch (Exception e){
e.printStackTrace();
}
}
}).start();
}
private void sendRequestWithHttpURLConnection() {
//开启线程来发起网络请求
new Thread(new Runnable() {
@Override
public void run() {
HttpURLConnection connection = null;
BufferedReader reader = null;
try{
URL url = new URL("https://www.baidu.com");//请求目标地址百度首页
connection = (HttpURLConnection) url.openConnection();
// connection.setRequestMethod("GET");
connection.setRequestMethod("POST");
DataOutputStream out = new DataOutputStream(connection.getOutputStream());
out.writeBytes("username=admin&password=123456");
connection.setConnectTimeout(8000);
connection.setReadTimeout(8000);
InputStream in = connection.getInputStream();
//下面对获取到的输入流进行读取
reader = new BufferedReader(new InputStreamReader(in));
StringBuilder response = new StringBuilder();
String line;
while ((line = reader.readLine()) != null){
response.append(line);
}
showResponse(response.toString());
}catch (Exception e){
e.printStackTrace();
}finally {
if (reader != null){
try{
reader.close();
}catch (IOException e){
e.printStackTrace();
}
}
if (connection != null){
connection.disconnect();
}
}
}
}).start();
}
private void showResponse(final String response) {
runOnUiThread(new Runnable() {//你明磊参数进行操作,将返回的数据进行读取,并将结果传入到了showResponse()方法中,将线程切换到主线程,然后将更新UI元素
@Override
public void run() {
//在这里进行UI操作
responseText.setText(response);
}
});
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:23.4.0'
compile 'com.squareup.okhttp3:okhttp:3.4.1'
}
添加上述依赖会自动下载两个库,一个是OkHttp库,一个是Okio库,后者是前者的通信机础,其中3.4.1是版本号。
OkHttp基本用法,首先创建OkHttpClient的实例,如下所示:
OkHttpClient client = new OkHttpClient();
接下来如果想要发起一条HTTP请求,就需要创建一个Request对象:
Request request = new Request.Builser().build();
当然上述代码只是创建一个空的Request对象,并没有实际作用,我们可以在最终的build()方法之前连缀很多其他的方法来丰富这个Request对象。比如可以通过url()方法来设置目标的网络地址,如下所示:
Request request = new Request.Builser()
.url("http://www.baidu.com")
build();
之后调用OkHttpClient的newCall()方法来创建一个Call对象,并调用它的execute()方法来发送请求并获取服务器返回的数据,写法如下:
Response response = client.newCall(request).execute();
其中Response对象就是服务器返回的数据了,我们可以使用如下写法开得到返回的具体内容:
String responseData = response.body().string();
如果是发起一条POST请求会比GET请求稍微复杂一点,我们需要先构建出一个RequestBody对象来存放待提交的参数,如下所示:
ReqestBody requestBody = new FormBody.Builder()
.add("username","admin")
.add("password","123456")
.build();
然后在Request.Builder中调用一下post()方法,并将RequestBody对象传入:
Request request = new Request.Builder()
.url("http://www.baidu.com")
.post(requestBody)
.build();
接下来就跟GET请求一样了,调用execute()方法来发送请求并获取服务器返回的数据即可。
现在对HTTPURLConnection项目改用Okhttp的方式实现一遍
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<Button
android:id="@+id/send_request"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Send Request"/>
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/response_text"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</ScrollView>
</LinearLayout>
MainActivity.java
package com.example.administrator.httpurlconnection;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import okhttp3.Call;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
TextView responseText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button sendRequest = (Button) findViewById(R.id.send_request);
responseText = (TextView) findViewById(R.id.response_text);
sendRequest.setOnClickListener(this);
}
@Override
public void onClick(View v) {
if (v.getId() == R.id.send_request){
// sendRequestWithHttpURLConnection();//调用 sendRequestWithHttpURLConnection()方法
sendRequestWithOkHttp();
}
}
private void sendRequestWithOkHttp() {
new Thread(new Runnable() {//开启个子线程
@Override
public void run() {
try {
OkHttpClient client = new OkHttpClient();//创建OkHttp实例
Request request = new Request.Builder()//发起一条HTTP请求
.url("http://www.baidu.com")
.build();
//调用OkHttpClient的newCall()方法来创建一个Call对象,并调用它的execute()方法来发送请求并获取服务器返回的数据
Response response = client.newCall(request).execute();
String responseData = response.body().string();
showResponse(responseData);//将服务器的数据返回到界面上
}catch (Exception e){
e.printStackTrace();
}
}
}).start();
}
private void sendRequestWithHttpURLConnection() {
//开启线程来发起网络请求
new Thread(new Runnable() {
@Override
public void run() {
HttpURLConnection connection = null;
BufferedReader reader = null;
try{
URL url = new URL("https://www.baidu.com");//请求目标地址百度首页
connection = (HttpURLConnection) url.openConnection();
// connection.setRequestMethod("GET");
connection.setRequestMethod("POST");
DataOutputStream out = new DataOutputStream(connection.getOutputStream());
out.writeBytes("username=admin&password=123456");
connection.setConnectTimeout(8000);
connection.setReadTimeout(8000);
InputStream in = connection.getInputStream();
//下面对获取到的输入流进行读取
reader = new BufferedReader(new InputStreamReader(in));
StringBuilder response = new StringBuilder();
String line;
while ((line = reader.readLine()) != null){
response.append(line);
}
showResponse(response.toString());
}catch (Exception e){
e.printStackTrace();
}finally {
if (reader != null){
try{
reader.close();
}catch (IOException e){
e.printStackTrace();
}
}
if (connection != null){
connection.disconnect();
}
}
}
}).start();
}
private void showResponse(final String response) {
runOnUiThread(new Runnable() {//你明磊参数进行操作,将返回的数据进行读取,并将结果传入到了showResponse()方法中,将线程切换到主线程,然后将更新UI元素
@Override
public void run() {
//在这里进行UI操作
responseText.setText(response);
}
});
}
}