当程序存在缺陷时，申请的连接忘记关闭，这时候，就存在连接泄漏了
我们使用druid时，可以配置如下参数进行用来关闭长时间不使用的连接
spring:
# 数据源配置
datasource:
druid:
# 统计监控信息
web-stat-filter:
enabled: true
# 可视化展示Druid的统计信息
stat-view-servlet:
enabled: true
filter:
# sql注入
wall:
enabled: true
db-type: mysql
slf4j:
enabled: true
statement-sql-pretty-format: true
# 保持连接sql
validation-query: SELECT 1 FROM DUAL
# 保持连接sql超时时间
validation-query-timeout: 600000
# 连接初始化sql
connection-init-sqls:
- SET NAMES utf8mb4
# 超时后释放连接设置时间
remove-abandoned-timeout-millis: 100
# 超时后释放连接开启
remove-abandoned: true
# 超时释放日志
log-abandoned: true
# 最大线程数
max-wait: 2000
# 最大等待时间
max-active: 20这里是abandoned相关配置
这样我们程序则会自动释放忘记关机的连接，并且输出日志信息
代码语言：javascript复制2022-01-15 18:49:29.560 ERROR 27396 --- [stroy-507383828] com.alibaba.druid.pool.DruidDataSource : abandon connection, owner thread: pool-2-thread-4, connected at : 1642240141966, open stackTrace
at java.lang.Thread.getStackTrace(Thread.java:1559)
at com.alibaba.druid.pool.DruidDataSource.getConnectionDirect(DruidDataSource.java:1496)
at com.alibaba.druid.filter.FilterChainImpl.dataSource_connect(FilterChainImpl.java:5059)
at com.alibaba.druid.filter.FilterAdapter.dataSource_getConnection(FilterAdapter.java:2756)
at com.alibaba.druid.filter.FilterChainImpl.dataSource_connect(FilterChainImpl.java:5055)
at com.alibaba.druid.filter.logging.LogFilter.dataSource_getConnection(LogFilter.java:917)
at com.alibaba.druid.filter.FilterChainImpl.dataSource_connect(FilterChainImpl.java:5055)
at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:1405)
at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:1397)
at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:100)
at org.springframework.jdbc.datasource.DataSourceUtils.fetchConnection(DataSourceUtils.java:158)
at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:116)
at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:79)
at org.mybatis.spring.transaction.SpringManagedTransaction.openConnection(SpringManagedTransaction.java:80)
at org.mybatis.spring.transaction.SpringManagedTransaction.getConnection(SpringManagedTransaction.java:67)
at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:337)
at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:86)
at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:62)
at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:325)
at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156)
at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109)
at com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor.intercept(MybatisPlusInterceptor.java:81)
at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:62)
at com.sun.proxy.$Proxy190.query(Unknown Source)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:151)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:145)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:140)
at com.baomidou.mybatisplus.core.override.MybatisMapperMethod.executeForMany(MybatisMapperMethod.java:166)
at com.baomidou.mybatisplus.core.override.MybatisMapperMethod.execute(MybatisMapperMethod.java:77)
at com.baomidou.mybatisplus.core.override.MybatisMapperProxy$PlainMethodInvoker.invoke(MybatisMapperProxy.java:148)
at com.baomidou.mybatisplus.core.override.MybatisMapperProxy.invoke(MybatisMapperProxy.java:89)
at com.sun.proxy.$Proxy121.selectList(Unknown Source)
at com.baomidou.mybatisplus.extension.toolkit.SimpleQuery.group(SimpleQuery.java:109)
