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Mon Mar 27 16:22:15 GMT+08:00 2023 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification.

Exception in thread "main" com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 1,405 milliseconds ago. The last packet sent successfully to the server was 1,405 milliseconds ago.

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)

at java.lang.reflect.Constructor.newInstance(Constructor.java:423)

at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)

at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:990)

at com.mysql.jdbc.ExportControlled.transformSocketToSSLSocket(ExportControlled.java:201)

at com.mysql.jdbc.MysqlIO.negotiateSSLConnection(MysqlIO.java:4869)

at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1656)

at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1217)

at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2189)

at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2220)

at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2015)

at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:768)

at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)

at java.lang.reflect.Constructor.newInstance(Constructor.java:423)

at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)

at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385)

at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323)

at java.sql.DriverManager.getConnection(DriverManager.java:664)

at java.sql.DriverManager.getConnection(DriverManager.java:247)

at com.itbaizhan.jdbcTest.main(jdbcTest.java:15)

Caused by: javax.net.ssl.SSLHandshakeException: No appropriate protocol (protocol is disabled or cipher suites are inappropriate)

at sun.security.ssl.HandshakeContext.<init>(HandshakeContext.java:171)

at sun.security.ssl.ClientHandshakeContext.<init>(ClientHandshakeContext.java:106)

at sun.security.ssl.TransportContext.kickstart(TransportContext.java:238)

at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:410)

at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:389)

at com.mysql.jdbc.ExportControlled.transformSocketToSSLSocket(ExportControlled.java:186)

... 18 more

老师我的代码和课的一样可是运行结果是上面这些为什么啊

JAVA 全系列/第三阶段：数据库编程/JDBC技术 5540楼

老师，直接在A的run方法里创建B的线程对象实现包装，在A类中联合，和课堂讲的区别在哪里呢

class A implements Runnable{
    @Override
    public void run() {
        Thread t3 =new Thread(new B());
        t3.start();
        for(int i=0;i<10;i++){
            if(i==5){
                try {
                    t3.join();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
            System.out.println(Thread.currentThread().getName()+":  A"+i);
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}
class B implements Runnable{

    @Override
    public void run() {
        for(int i=0;i<20;i++){
            System.out.println(Thread.currentThread().getName()+"  B"+i);
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}

public class TestJoinThread {
    public static void main(String[] args) {
        Thread t1 = new Thread(new A());
        t1.start();

        for(int i=0;i<10;i++){
            System.out.println(Thread.currentThread().getName()+"      "+i);
            //当主线程迭代因子为2时，并入A线程
            if(i==2){
                try {
                    t1.join();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}

JAVA 全系列/第二阶段：JAVA 基础深化和提高/多线程技术 5541楼

import re

import requests

from fake_useragent import UserAgent

url = 'https://www.qidian.com/rank/yuepiao/'

headers = {'User-Agent':UserAgent().chrome}

res = requests.get(url,headers = headers)

res.encoding = 'utf-8'

with open('tmp.html','w',encoding='utf-8') as f:

f.write(res.text)

rs =re.findall('<div class="book-mid-info"> <h2><a href=".+?>(.+)</a>',res.text)

print(rs)