15-09-2020 13:25:46 INFO - java.sql.SQLNonTransientConnectionException: Could not create connection to database server.
15-09-2020 13:25:46 INFO -    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:526)
15-09-2020 13:25:46 INFO -    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:513)
...
15-09-2020 13:25:46 INFO - Caused by: java.lang.ArrayIndexOutOfBoundsException: 24
15-09-2020 13:25:46 INFO -    at com.mysql.cj.mysqla.io.Buffer.readInteger(Buffer.java:271)
15-09-2020 13:25:46 INFO -    at com.mysql.cj.mysqla.io.MysqlaCapabilities.setInitialHandshakePacket(MysqlaCapabilities.java:62)
15-09-2020 13:25:46 INFO -    at com.mysql.cj.mysqla.io.MysqlaProtocol.readServerCapabilities(MysqlaProtocol.java:482)
15-09-2020 13:25:46 INFO -    at com.mysql.cj.mysqla.io.MysqlaProtocol.beforeHandshake(MysqlaProtocol.java:367)
15-09-2020 13:25:46 INFO -    at com.mysql.cj.mysqla.io.MysqlaProtocol.connect(MysqlaProtocol.java:1412)
15-09-2020 13:25:46 INFO -    at com.mysql.cj.mysqla.MysqlaSession.connect(MysqlaSession.java:132)
15-09-2020 13:25:46 INFO -    at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:1726)

20/09/05 02:41:58 INFO DataxImport: 2020-09-05 02:41:58.819 [0-0-0-writer] WARN CommonRdbmsWriter$Task - 回滾此次寫入, 采用每次寫入一行方式提交. 因?yàn)?No operations allowed after statement closed.
20/09/05 02:41:58 INFO DataxImport: 2020-09-05 02:41:58.824 [0-0-0-writer] ERROR WriterRunner - Writer Runner Received Exceptions:
20/09/05 02:41:58 INFO DataxImport: com.alibaba.datax.common.exception.DataXException: Code:[DBUtilErrorCode-05], Description:[往您配置的寫入表中寫入數(shù)據(jù)時(shí)失敗.]. - com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure
20/09/05 02:41:58 INFO DataxImport:
20/09/16 00:47:58 INFO : The last packet successfully received from the server was 4,882 milliseconds ago. The last packet sent successfully to the server was 4,883 milliseconds ago.
20/09/16 00:47:58 INFO :    at com.mysql.cj.jdbc.exceptions.SQLError.createCommunicationsException(SQLError.java:590)
20/09/16 00:47:58 INFO :    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:57)
20/09/16 00:47:58 INFO : Caused by: com.mysql.cj.core.exceptions.CJCommunicationsException: Communications link failure
20/09/16 00:47:58 INFO :
。。。
20/09/16 00:47:58 INFO : Caused by: java.net.SocketException: 連接超時(shí) (Write failed)
20/09/16 00:47:58 INFO :    at java.net.SocketOutputStream.socketWrite0(Native Method)
。。。

這種超時(shí)錯(cuò)誤，如果拿到度娘去搜，一般都會(huì)說(shuō)是wait_timeout,但是這種問(wèn)題很好定位；而且日志中3秒或者更少的時(shí)間就報(bào)錯(cuò)的話，而且是在重復(fù)使用某個(gè)connection的時(shí)候就報(bào)錯(cuò)了，就很可能不是這個(gè)問(wèn)題了。需要進(jìn)一步分析。

而光憑這些報(bào)錯(cuò)信息，是很難定位到問(wèn)題的確切原因的，作為研發(fā)的話，很容易想到環(huán)境問(wèn)題或者網(wǎng)絡(luò)問(wèn)題。

中途解決過(guò)程經(jīng)歷了各種猜測(cè)，各種嘗試，都沒(méi)有見效，最后發(fā)現(xiàn)自己被強(qiáng)迫使用的mysql的6.0.6這個(gè)版本的驅(qū)動(dòng)，這個(gè)版本的驅(qū)動(dòng)不穩(wěn)定，可能出現(xiàn)奇怪的問(wèn)題。更換為5.x版本或者8.x版本都可以解決這個(gè)問(wèn)題。

發(fā)出來(lái)希望同道中人能避免被這個(gè)問(wèn)題惡心到。

如何知道自己代碼實(shí)際使用到哪個(gè)jar下面的驅(qū)動(dòng)呢？有的時(shí)候錯(cuò)誤日志能體現(xiàn)出來(lái)，有的時(shí)候可能需要打印確切的日志信息

在獲取connection以后，調(diào)用這個(gè)方法即可。

我的問(wèn)題比較坑的地方在于，不知道誰(shuí)在jre的ext目錄下放了這個(gè):mysql-connector-java-6.0.6.jar:6.0.6

導(dǎo)致所有的java程序必須只能用這個(gè)jar（基于雙親委派）

public static void printJar(Object o) {
? ? ? ? String className = o.getClass().getName();
? ? ? ? String classNamePath = className.replace(".", "/") + ".class";
? ? ? ? URL is = o.getClass().getClassLoader().getResource(classNamePath);
? ? ? ? String ppath = is.getFile();
? ? ? ? ppath = org.apache.commons.lang3.StringUtils.replace(ppath, "%20", " ");
? ? ? ? logger.info("類所在的jar為");
? ? ? ? logger.info(org.apache.commons.lang3.StringUtils.removeStart(ppath, "/"));
? ? }

連接MySQL錯(cuò)誤create connection SQLException, url: jdbc:mysql://localhost:3306/*****?

具體報(bào)錯(cuò)如下：

2018-11-12 16:14:21.704 ERROR 9752 --- [eate-1537371824] com.alibaba.druid.pool.DruidDataSource : create connection SQLException, url: jdbc:mysql://localhost:3306/*****?allowMultiQueries=true&useUnicode=true&characterEncoding=UTF-8&useSSL=false, errorCode 1193, state HY000

java.sql.SQLException: Unknown system variable 'query_cache_size'
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:957)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3878)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3814)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2478)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2625)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2547)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2505)
at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1370)
at com.mysql.jdbc.ConnectionImpl.loadServerVariables(ConnectionImpl.java:3862)
at com.mysql.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:3290)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2299)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2085)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:795)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:44)
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:404)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:400)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:327)
at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:156)
at com.alibaba.druid.filter.stat.StatFilter.connection_connect(StatFilter.java:218)
at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:150)
at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1560)
at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1623)
at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2468)

解決方法

本人是MySQL版本問(wèn)題,用的是MySQL8.0,將MySQL驅(qū)動(dòng)改成如下:5.1.6

<!--MySQL驅(qū)動(dòng)-->
<dependency>
? <groupId>mysql</groupId>
? <artifactId>mysql-connector-java</artifactId>
? <version>5.1.6</version>
</dependency>

修改后的連接信息如下:

spring:
? ? datasource:
? ? ? ? type: com.alibaba.druid.pool.DruidDataSource
? ? ? ? driverClassName: com.mysql.jdbc.Driver
? ? ? ? druid:
? ? ? ? ? ? first: ?#數(shù)據(jù)源1
? ? ? ? ? ? ? ? url: jdbc:mysql://localhost:3306/數(shù)據(jù)庫(kù)名稱?allowMultiQueries=true&useUnicode=true&characterEncoding=UTF-8
? ? ? ? ? ? ? ? username: *****
? ? ? ? ? ? ? ? password: *****
........................

or 2020/05/28 加

spring:
  http:
    encoding:
      charset: UTF-8
      force: true
      enabled: true
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    driverClassName: com.mysql.jdbc.Driver
 
    platform: mysql
    url: jdbc:mysql://127.0.0.1:3306/數(shù)據(jù)庫(kù)名稱?useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull&serverTimezone=GMT%2B8
    username: XXXXXX
    password: XXXXXX
    #初始化鏈接數(shù)
    initialSize: 5
    #最小的空閑連接數(shù)
    minIdle: 5
    #最大活動(dòng)連接數(shù)
    maxActive: 20
    #從池中取連接的最大等待時(shí)間，單位ms
    maxWait: 60000
    #每XXms運(yùn)行一次空閑連接回收器
    timeBetweenEvictionRunsMillis: 60000
    #池中的連接空閑XX毫秒后被回收
    minEvictableIdleTimeMillis: 300000
    validationQuery: SELECT1FROMDUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    filters: stat,wall,log4j
    logSlowSql: true

以上為個(gè)人經(jīng)驗(yàn)，希望能給大家一個(gè)參考，也希望大家多多支持腳本之家。

您可能感興趣的文章: