dbs.properties 的配置
user=root
password=123456
url=jdbc:mysql://localhost:3306/homework
driver=com.mysql.jdbc.Driver
c3p0.minPoolSize=3
c3p0.maxPoolSize=25
c3p0.initPoolSize=5
c3p0.acquireIncrement=3
c3p0.acquireRetryAttempts=60
c3p0.acquireRetryDelay=1000
c3p0.autoCommitOnClose=false
c3p0.checkoutTimeout=3000
c3p0.idleConnectionTestPeriod=120
c3p0.maxIdleTime=600
c3p0.testConnectionOnCheckin=false
c3p0.maxStatements=8
c3p0.maxStatementsPerConnection=5
