sql util

BUILD

@@ -28,6 +28,15 @@ java_library(
   ],
 )    
 
+java_library(
+  name = "sql_lib",
+  srcs = glob(["src/sql/*.java"]),
+  deps = [
+    "@commons_pool//jar",
+    "@commons_dbcp//jar",
+  ],
+)
+
 java_test(
   name = "ziptest",
   srcs = ["test/ZipTest.java"],

WORKSPACE

@@ -46,3 +46,14 @@ maven_jar(
   sha1 = "1b6c4ff09ce03f3052429139c2a68e295cae6604",
 )
 
+maven_jar(
+  name = "commons_pool",
+  artifact = "commons-pool:commons-pool:1.6",
+  sha1 = "4572d589699f09d866a226a14b7f4323c6d8f040",
+)
+
+maven_jar(
+  name = "commons_dbcp",
+  artifact = "commons-dbcp:commons-dbcp:1.4",
+  sha1 = "30be73c965cc990b153a100aaaaafcf239f82d39",
+)

src/sql/DBUtil.java

@@ -0,0 +1,94 @@
+package duckutil.sql;
+
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+
+
+import org.apache.commons.pool.ObjectPool;
+import org.apache.commons.pool.impl.GenericObjectPool;
+import org.apache.commons.dbcp.ConnectionFactory;
+import org.apache.commons.dbcp.PoolingDriver;
+import org.apache.commons.dbcp.PoolableConnectionFactory;
+import org.apache.commons.dbcp.DriverManagerConnectionFactory;
+
+import java.util.Properties;
+
+public class DBUtil
+{
+
+    private static void loadDriver(String driver)
+        throws SQLException
+    {
+        try
+        {
+            Class.forName(driver).newInstance();
+        }
+        catch(Exception e)
+        {
+            throw new SQLException("Unable to load driver: " + driver);
+        }
+    }
+
+    public static void openConnectionPool(String pool_name, String driver_class, String uri, String user, String pass, int max_active, int max_idle)
+        throws SQLException
+    {
+
+        Properties props = new Properties();
+        props.put("autoReconnect","true");
+        props.put("user",user);
+        props.put("password",pass);
+
+        loadDriver(driver_class);
+        loadDriver("org.apache.commons.dbcp.PoolingDriver");
+
+
+        GenericObjectPool connectionPool = new GenericObjectPool(null);
+
+        connectionPool.setMaxActive(max_active);
+        connectionPool.setMaxIdle(max_idle);
+
+        ConnectionFactory connectionFactory = new DriverManagerConnectionFactory(uri, props);
+
+        new PoolableConnectionFactory(connectionFactory,connectionPool,null,null,false,true);
+
+        PoolingDriver driver = (PoolingDriver) DriverManager.getDriver("jdbc:apache:commons:dbcp:");
+
+        driver.registerPool(pool_name,connectionPool);
+
+    }
+
+
+    public static Connection openConnection(String pool_name)
+        throws SQLException
+    {
+        Connection conn = DriverManager.getConnection("jdbc:apache:commons:dbcp:" + pool_name);
+        conn.setAutoCommit(true);
+        return conn;
+
+    }
+    public static void safeClose(Connection conn)
+    {
+        if (conn==null) return;
+        try
+        {
+            conn.close();
+        }
+        catch(SQLException e)
+        {
+            e.printStackTrace();
+
+        }
+    }
+
+    public static void printDriverStats(String pool_name) throws Exception
+    {
+        PoolingDriver driver = (PoolingDriver) DriverManager.getDriver("jdbc:apache:commons:dbcp:");
+        ObjectPool connectionPool = driver.getConnectionPool(pool_name);
+        System.out.println("NumActive: " + connectionPool.getNumActive());
+        System.out.println("NumIdle: " + connectionPool.getNumIdle());
+    }
+
+
+}