OkHttp3 的基本使用

依赖

    
    
        com.squareup.okhttp3
        okhttp
        3.14.9
    
    
    
        com.squareup.okio
        okio
        2.6.0
    
    
    
        org.jsoup
        jsoup
        1.13.1
    
    
    
        commons-io
        commons-io
        2.8.0
    

工具封装

import okhttp3.Call;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import org.apache.commons.io.FileUtils;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;

import java.io.File;
import java.io.InputStream;
import java.net.InetSocketAddress;
import java.net.Proxy;
import java.util.concurrent.TimeUnit;

public class HttpUtil {

    private static final String HOST = "127.0.0.1";
    private static final int PORT = 1080;

    private HttpUtil() {}

    static {
        System.setProperty("https.protocols","TLSv1,TLSv1.1,TLSv1.2");
    }

    /**
     * 创建okHttp客户端
     */
    private static OkHttpClient okHttpClient = new OkHttpClient.Builder()
            .connectTimeout(60, TimeUnit.SECONDS)
            .readTimeout(60,TimeUnit.SECONDS)
            .followRedirects(true)
            //有代理就使用代理，没有代理注释掉
            .proxy(new Proxy(Proxy.Type.HTTP, new InetSocketAddress(HOST, PORT)))
            .build();

    /**
     * 结合jsoup爬取dom，jsoup内部使用httpclient，效率不好
     * @param url
     * @param host
     * @return
     * @throws Exception
     */
    public static Document getDoc(String url,String host) throws Exception {
        Request request = new Request.Builder().url(url).get().build();
        Call call = okHttpClient.newCall(request);
        String body = call.execute().body().string();
        return Jsoup.parse(body,host);
    }

    /**
     * 下载网络文件
     * @param url
     * @param file
     * @throws Exception
     */
    public static void download(String url,File file) throws Exception {
        Request request = new Request.Builder().url(url).get().build();
        Call call = okHttpClient.newCall(request);
        try(InputStream inputStream = call.execute().body().byteStream()) {
            FileUtils.copyInputStreamToFile(inputStream,file);
        }catch (Exception e){
            throw e;
        }
    }
}