Reproduced please indicate the original address: https://www.cnblogs.com/ygj0930/p/11280540.html

A: DRUID connection pool Profile

　　Ali produced "Born to monitor" the database connection pool, functionality, performance, scalability, more than other database connection pool, while adding log monitoring, can be a good monitor implementation DB connection pool and SQL. And the only one to solve the problem of leakage PSCache connected connection pool.

II: introducing bag or jar add dependencies

 <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid</artifactId>
        <version>1.0.18</version>
 </dependency>

III: Configure Connection Pool

　　1: Create a configuration file to configure druid.properties

url jdbcUrl connection to the database: MySQL: jdbc: MySQL: // localhost: 3306 / the Test 

username username database 
password password database 
driverClassName driver class name. The url automatic identification, which can be equipped with an unworthy, if not based on the configuration druid automatically identify dbType url, 
then select the appropriate driverClassName (recommended configuration) 
to establish the number of physical connections during initialization initialSize. Initialization occurs in displaying calling the init method, or the first time the getConnection 
for maxActive the maximum number of connection pools 
maxIdle no longer used, the configuration did not effect 
the minimum number of connection pools minIdle 
when connected maxWait obtain the maximum waiting time, in milliseconds.

　　2: SpringBoot project directly to the configuration in application.properties

Database access configuration # 
# primary data source, the default 
spring.datasource.type = com.alibaba.druid.pool.DruidDataSource 
spring.datasource.driver - class -name = com.mysql.jdbc.Driver 
spring.datasource.url = JDBC : MySQL: // localhost: 3306 / Test 
spring.datasource.username = the root 
spring.datasource.password = 123456 

# added to set the following connection pool, is applied to all of the above data sources 
# initial size, minimum, maximum 
spring.datasource .initialSize =. 5 
spring.datasource.minIdle =. 5 
spring.datasource.maxActive = 20 is 
# configuration acquiring connection waiting timeout time 
spring.datasource.maxWait = 60000
# Intervals the frequency of such detection, an idle connection is detected to be closed, in milliseconds 
spring.datasource.timeBetweenEvictionRunsMillis = 60000 
# arranged a minimum connection time survival pool milliseconds 
spring.datasource.minEvictableIdleTimeMillis = 300000 
Spring. datasource.validationQuery = the SELECT. 1 the FROM the DUAL 
spring.datasource.testWhileIdle = to true 
spring.datasource.testOnBorrow = to false 
spring.datasource.testOnReturn = to false 
# open PSCache, and specifies the size of each connection PSCache 
spring.datasource.poolPreparedStatements = to true 
Spring .datasource.maxPoolPreparedStatementPerConnectionSize = 20 
# configure monitoring statistics intercepted filters, after removing the monitoring interface sql not statistics, 'Wall'Firewalls 
spring.datasource.filters = STAT, Wall, log4j 
# mergeSql opened by connectProperties property function; slow SQL record 
spring.datasource.connectionProperties = = druid.stat.mergeSql to true ; druid.stat.slowSqlMillis = 5000 
# merge multiple monitoring data of a DruidDataSource 
# spring.datasource.useGlobalDataSourceStat = to true

Four: the definition of DBUtils Tools

Initializing the connection pool with connection profiles, and a method for obtaining a series connection defines a method of operating a database.

Five: Use the DAO layer

dbutil database operations.

Six: Druid monitoring using statistical functions

https://github.com/alibaba/druid/wiki/%E9%85%8D%E7%BD%AE_StatFilter

Seven: Druid page using the built-in monitor

https://github.com/alibaba/druid/wiki/%E9%85%8D%E7%BD%AE_StatViewServlet%E9%85%8D%E7%BD%AE

Eight: Configure SQL injection defense

https://github.com/alibaba/druid/wiki/%E9%85%8D%E7%BD%AE-wallfilter

Nine: SQL execution logging configuration

https://github.com/alibaba/druid/wiki/%E9%85%8D%E7%BD%AE_LogFilter

Ten: Connection Leak Monitoring

https://github.com/alibaba/druid/wiki/%E8%BF%9E%E6%8E%A5%E6%B3%84%E6%BC%8F%E7%9B%91%E6%B5%8B

Eleven: PSCache memory footprint issues

https://github.com/alibaba/druid/wiki/Oracle%E6%95%B0%E6%8D%AE%E5%BA%93%E4%B8%8BPreparedStatementCache%E5%86%85%E5%AD%98%E9%97%AE%E9%A2%98%E8%A7%A3%E5%86%B3%E6%96%B9%E6%A1%88

12: Slow implementation of SQL record

https://github.com/alibaba/druid/wiki/%E9%85%8D%E7%BD%AE_StatFilter

Thirteen: Database Password Encryption

https://github.com/alibaba/druid/wiki/%E4%BD%BF%E7%94%A8ConfigFilter

Fourteen: SpringBoot configured Druid

https://github.com/alibaba/druid/tree/master/druid-spring-boot-starter

Druid connection pool usage