只有个页面，连接数据库的就是一个getSession()， 一个调用Dao实现类的方法；
Dao实现类如下：
public class DptDaoImp implements DptDao {
public List<Dpt> show_Dpt() {
String sql ="SELECT * FROM dpt";
Connection conn=null;
List<Dpt> dpt_List=null;
ComboPooledDataSource dataSource =new ComboPooledDataSource();
try {
conn = dataSource.getConnection();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
QueryRunner runner =new QueryRunner();
try {
dpt_List = runner.query(conn, sql, new BeanListHandler<Dpt>(Dpt.class));
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
conn.close(); //此处已经释放连接
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return dpt_List;
}
}
c3p0的配置：
<c3p0-config>
<default-config>
<property name="jdbcUrl">jdbc:mysql://localhost:3306/rsp</property>
<property name="driverClass">com.mysql.jdbc.Driver</property>
<property name="user">root</property>
<property name="password">root</property>
<property name="initialPoolSize">10</property>
<!--连接池中保留的最小连接数。-->
<property name="minPoolSize">10</property>
<!--连接池中保留的最大连接数。Default: 15 -->
<property name="maxPoolSize">100</property>
<!--最大空闲时间,10秒内未使用则连接被丢弃。若为0则永不丢弃。Default: 0 -->
<property name="maxIdleTime">5</property>
<property name="maxStatements">0</property>
<property name="maxStatementsPerConnection">0</property>
在mysql中my.ini 中最大连接 max_connections (已改为1000)
现状： 登录账号后，交替点那两个模块，60次左右就挂了，机器卡死，大大们求救啊！
出现下列提示：
警告: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@36e15d3f -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception:
com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Data source rejected establishment of connection, **message from server: "Too many connections"**
at sun.reflect.GeneratedConstructorAccessor18.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
at com.mysql.jdbc.Util.getInstance(Util.java:384)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1015)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:989)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:984)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1105)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2186)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:787)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:49)
at sun.reflect.GeneratedConstructorAccessor14.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:357)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)
at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
