今天把分布式事务弄好以后，后面一直报连接错误

先来说这个错误：XA resource 'XXXXdatasource': end for XID '' raised -7: the XA resource has become unavailable

这个算是mysql对于Atomikos的一个小bug

 官方的解释： 

A possible workaround might be to try and start TransactionsEssentials with the parametercom.atomikos.icatch.serial_jta_transactions set to false.

com.atomikos.icatch.serial_jta_transactions=false

Also, make sure to set the following property on the MySQL datasource:

 pinGlobalTxToPhysicalConnection="true"　　

我在试了com.atomikos.icatch.serial_jta_transactions这个以后，还是一样的，没有任何反应。照常报错，数据库还是一直连接不，第一次登陆访问数据库都不行

于是换一种方式pinGlobalTxToPhysicalConnection="true"；

但是我是用的druid，也挺无奈，于是在url上面添加了一段，惊奇的发现。卧槽，居然可以了

配置文件:

spring: 
    datasource:
        druid: 
          type: com.alibaba.druid.pool.xa.DruidXADataSource
          driver-class-name: com.mysql.jdbc.Driver
          platform: mysql
          default: 
            # 资源标识
            uniqueResourceName: default
            # 数据源类名
            xaDataSourceClassName: com.alibaba.druid.pool.xa.DruidXADataSource
            xaProperties: 
              # 数据源配置
              driverClassName: com.mysql.jdbc.Driver
              url: jdbc:mysql://xxxxxxxx:3306/mypinyu?useUnicode=true&characterEncoding=UTF-8&allowMultiQueries=true&useSSL=false&pinGlobalTxToPhysicalConnection=true
              username: root
              password: Goodlan@123
              initialSize: 5
              minIdle: 5
              maxActive: 20
              maxWait: 60000
              timeBetweenEvictionRunsMillis: 60000
              minEvictableIdleTimeMillis: 300000
              validationQuery: SELECT 1
              testWhileIdle: true
              testOnBorrow: false
              testOnReturn: false
          second: 
            # 资源标识
            uniqueResourceName: second
            # 数据源类名
            xaDataSourceClassName: com.alibaba.druid.pool.xa.DruidXADataSource
            xaProperties: 
              driverClassName: com.mysql.jdbc.Driver
              url: jdbc:mysql://localhost:3306/mypinyu?useUnicode=true&characterEncoding=UTF-8&allowMultiQueries=true&useSSL=false&pinGlobalTxToPhysicalConnection=true
              username: root
              password: admin
              initialSize: 5
              minIdle: 5
              maxActive: 20
              maxWait: 60000
              timeBetweenEvictionRunsMillis: 60000
              minEvictableIdleTimeMillis: 300000
              #验证连接是否可用，使用的SQL语句
              validationQuery: SELECT 1
              #指明连接是否被空闲连接回收器(如果有)进行检验.如果检测失败,则连接将被从池中去除.
              testWhileIdle: true
              #借出连接时不要测试，否则很影响性能
              testOnBorrow: false
              testOnReturn: false
#jta相关参数配置
jta:
  log-dir: classpath:tx-logs
  transaction-manager-id: txManager        
        
logging.config:
  classpath: log4j2.xml
  
#返回视图的前缀   目录对应src/main/webapp下
spring.mvc.view.prefix: /WEB-INF/jsp/
#返回的后缀
spring.mvc.view.suffix: .jsp