webmagic框架protocol_version问题处理

异常描述：

 1 javax.net.ssl.SSLException: Received fatal alert: protocol_version
 2     at sun.security.ssl.Alerts.getSSLException(Alerts.java:208)
 3     at sun.security.ssl.Alerts.getSSLException(Alerts.java:154)
 4     at sun.security.ssl.SSLSocketImpl.recvAlert(SSLSocketImpl.java:2020)
 5     at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1127)
 6     at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1367)
 7     at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1395)
 8     at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1379)
 9     at org.apache.http.conn.ssl.SSLConnectionSocketFactory.createLayeredSocket(SSLConnectionSocketFactory.java:394)
10     at org.apache.http.conn.ssl.SSLConnectionSocketFactory.connectSocket(SSLConnectionSocketFactory.java:353)
11     at org.apache.http.impl.conn.DefaultHttpClientConnectionOperator.connect(DefaultHttpClientConnectionOperator.java:141)
12     at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.connect(PoolingHttpClientConnectionManager.java:353)
13     at org.apache.http.impl.execchain.MainClientExec.establishRoute(MainClientExec.java:380)
14     at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:236)
15     at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:184)
16     at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:88)
17     at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:110)
18     at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:184)
19     at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:82)
20     at us.codecraft.webmagic.downloader.HttpClientDownloader.download(HttpClientDownloader.java:85)
21     at us.codecraft.webmagic.Spider.processRequest(Spider.java:404)
22     at us.codecraft.webmagic.Spider.access$000(Spider.java:61)
23     at us.codecraft.webmagic.Spider$1.run(Spider.java:320)
24     at us.codecraft.webmagic.thread.CountableThreadPool$1.run(CountableThreadPool.java:74)
25     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
26     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
27     at java.lang.Thread.run(Thread.java:748)

原因：webmagic默认的HttpClient只会用TLSv1去请求，对于某些只支持TLS1.2的站点（例如https://juejin.im/） ，就会报错；

解决方法：https://github.com/code4craft/webmagic/issues/701

标签：java,http,protocol,ssl,version,apache,org,SSLSocketImpl,webmagic
来源： https://www.cnblogs.com/mxh-java/p/15440272.html