connectionwrappersample.java

来自「Java示例100」· Java 代码 · 共 48 行

/*
 * This sample shows how to list all the names from the EMP table
 * first using a normal connection and then a wrapped connectiion
 * and then a deeply nested wrapper
 */

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

public class ConnectionWrapperSample
{
  public static void main (String args [])
       throws SQLException
  {
    DriverManager.registerDriver(new oracle.jdbc.OracleDriver());
    OracleConnection conn =
      (OracleConnection)(DriverManager.getConnection ("jdbc:oracle:oci8:@", "hr", "hr"));

    printEmployees( conn );

    // Now wrap the connection
    OracleConnectionWrapper wrappedConnection = 
        new OracleConnectionWrapper( conn );
    printEmployees( wrappedConnection);

    // Wrap it in may layers
    for( int i=0; i<20; i++ )
       wrappedConnection = 
            new OracleConnectionWrapper( wrappedConnection );
    printEmployees( wrappedConnection);


    conn.close();
  }

public static void printEmployees( oracle.jdbc.OracleConnection conn ) throws SQLException
  {
    Statement stmt = conn.createStatement ();
    ResultSet rset = stmt.executeQuery ("select LAST_NAME from EMPLOYEES");
    while (rset.next ())
      System.out.print(rset.getString(1) + " ");
    rset.close();
    stmt.close();
    System.out.println();
    System.out.println();
  }
}