HikariPool連接池的使用

 

測試代碼： 使用連接池用時500ms, 不使用連接池用時8s, 相差16倍. 
每個連接的創建都要經過http握手、密碼認證，這里比較耗時， mysql給每個connection分配一個id

public class DBpoolTest {

    private static final HikariDataSource ds;

    static {
        HikariConfig conf = new HikariConfig();
        conf.setUsername("root");
        conf.setPassword("root");
        conf.setJdbcUrl("jdbc:mysql://localhost:3306/abc");
        ds = new HikariDataSource(conf);
    }

    @Test
    public void test_1() throws SQLException {
        long st = System.currentTimeMillis();
        for (int i = 0; i < 1000; i++) {
            Connection connection = ds.getConnection();
            Statement statement = connection.createStatement();
            ResultSet resultSet = statement.executeQuery("select now() from dual");
            while (resultSet.next()) {
                System.out.println(resultSet.getString(1));
            }
            connection.close();
        }
        System.out.println(System.currentTimeMillis() - st);
    }

    @Test
    public void test_2() throws SQLException {
        long st = System.currentTimeMillis();
        for (int i = 0; i < 1000; i++) {
            Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/abc", "root", "root");
            Statement statement = connection.createStatement();
            ResultSet resultSet = statement.executeQuery("select now() from dual");
            while (resultSet.next()) {
                System.out.println(resultSet.getString(1));
            }
            connection.close();
        }
        System.out.println(System.currentTimeMillis() - st);
    }
}

　　

連接池回收過程

 HikariDataSource datasource= new HikariDataSource( xxxx );

Connection cn = datasource.getConnection();

try {

     cn.doXXX()

} finnally(){

     connection.close();// connection的實現類（代理類）自己會調用hikariPool.evictConnection(cn) ,將此連接回收到pool中

}

connection回收到池中是連接池自己做的事， 業務代碼不用關心物理連接是否真的關閉,只需要調用close（）方法

Hikari中connection.close()的實現 

 

Druid close（）實現