example1.java

本书中的源代码是以JBuilder工程形式组织的

package jdbcexample;
import java.sql.*;
import javax.naming.*;
import javax.sql.*;
import java.util.Properties;
import javax.rmi.PortableRemoteObject;

public class Example1 {

  public static void main(String[] args) {
    DataSource ds = null;
Context ctx = null;
Connection myConn = null;
try {
  /* 获得WebLogic ServerJNDI初始上下文信息
   */
  ctx = getInitialContext();
  /* 建立数据源对象
   */
  ds = (javax.sql.DataSource)
      ctx.lookup("myDataSource");
}
catch (Exception E) {
   System.out.println("Init Error: " + E);
}
Statement myStatement=null;
ResultSet myResultSet=null;
try {
  //建立连接
  myConn = ds.getConnection();
  // 建立语句对象
  myStatement = myConn.createStatement();
  //建立结果集对象
   myResultSet = myStatement.executeQuery(
      "SELECT full_name from employee"
      );
 //遍历结果集对象，访问每一条记录，输出full_name字段
  while(myResultSet.next())
 {
   System.out.println("the employee full name is " +  myResultSet.getString("full_name"));
 }
 //关闭结果集
  myResultSet.close();
}
catch (SQLException e) {
  System.out.println("Error code = " + e.getErrorCode());
  System.out.println("Error message = " + e.getMessage());
}
finally {
  try {
    // close the Statement object using the close() method
    if (myStatement != null) {
      myStatement.close();
    }
    // close the Connection object using the close() method
    if (myConn != null) {
      myConn.close();
    }
  }
  catch (SQLException e) {
    System.out.println("Error code = " + e.getErrorCode());
    System.out.println("Error message = " + e.getMessage());
  }
}

  }
  private static Context getInitialContext() throws Exception {
         String url = "t3://localhost:7001";
         String user = "system";
         String password = "security";
         Properties properties = null;
         try {
           properties = new Properties();
           properties.put(Context.INITIAL_CONTEXT_FACTORY,
               "weblogic.jndi.WLInitialContextFactory");
           properties.put(Context.PROVIDER_URL, url);
           if (user != null) {
             properties.put(Context.SECURITY_PRINCIPAL, user);
             properties.put(Context.SECURITY_CREDENTIALS, password == null ? "" : password);
           }
           return new InitialContext(properties);
         }
         catch(Exception e) {
           throw e;
         }
       }

}