ccache1.java

Java示例100

/**
 *  JDBC 2.0 Spec doesn't mandate that JDBC vendors implement a 
 *  Connection Cache. However, we implemented a basic one with 2
 *  schemes as an Example.
 *
 *  There are 3 cache schemes: DYNAMIC_SCHEME (default)
 *                             FIXED_RETURN_NULL_SCHEME
 *                             FIXED_WAIT_SCHEME
 *
 *  A Sample demo to illustrate DYNAMIC_SCHEME of OracleConnectionCacheImpl.
 *  Dynamic Scheme :  This is the default scheme. New connections could be 
 *  created beyond the Max limit upon request but closed and freed when the 
 *  logical connections are closed. When all the connections are active and 
 *  busy, requests for new connections willend up creating new physical 
 *  connections. But these physical connections are closed when the
 *  corresponding logical connections are closed. A typical grow and shrink 
 *  scheme.
 *  Please compare with CCache2.java and CCache3.java 
 *
 * Please use jdk1.2 or later version
 */

import java.sql.*;
import javax.sql.*;
import oracle.jdbc.*;
import oracle.jdbc.pool.*;

class CCache1
{
  public static void main (String args [])
       throws SQLException
  {
    OracleConnectionCacheImpl ods = new OracleConnectionCacheImpl();
    String url = "jdbc:oracle:oci8:@";
    try {
      String url1 = System.getProperty("JDBC_URL");
      if (url1 != null)
        url = url1;
    } catch (Exception e) {
      // If there is any security exception, ignore it
      // and use the default
    }

    ods.setURL(url);
    ods.setUser("hr");
    ods.setPassword("hr");

     // Set the Max Limit
    ods.setMaxLimit (3);

    Connection conn1 = null;
    conn1 = ods.getConnection();
    if (conn1 != null)
      System.out.println("Connection 1 " + " Succeeded!");
    else
      System.out.println("Connection 1 " + " Failed !!!");

    Connection conn2 = null;
    conn2 = ods.getConnection();
    if (conn2 != null)
      System.out.println("Connection 2 " + " Succeeded!");
    else
      System.out.println("Connection 2 " + " Failed !!!");

    Connection conn3 = null;
    conn3 = ods.getConnection();
    if (conn3 != null)
      System.out.println("Connection 3 " + " Succeeded!");
    else
      System.out.println("Connection 3 " + " Failed !!!");

    Connection conn4 = null;
    conn4 = ods.getConnection();
    if (conn4 != null)
      System.out.println("Connection 4 " + " Succeeded!");
    else
      System.out.println("Connection 4 " + " Failed !!!");

    Connection conn5 = null;
    conn5 = ods.getConnection();
    if (conn5 != null)
      System.out.println("Connection 5 " + " Succeeded!");
    else
      System.out.println("Connection 5 " + " Failed !!!");


    System.out.println("Active size : " + ods.getActiveSize());
    System.out.println("Cache Size is " + ods.getCacheSize());

    // Close 3 logical Connections
    conn1.close();
    conn2.close();
    conn3.close();

    System.out.println("Active size : " + ods.getActiveSize());
    System.out.println("Cache Size is " + ods.getCacheSize());

    // close the Data Source
    ods.close();

    System.out.println("Active size : " + ods.getActiveSize());
    System.out.println("Cache Size is " + ods.getCacheSize());
  }
}