Update QuickStart.java

Author: nsundara

java/jdbc/ConnectionSamples/QuickStart.java

@@ -1,8 +1,12 @@
-/* Copyright (c) 2021, Oracle and/or its affiliates. All rights reserved.*/
+/* Copyright (c) 2021, Oracle and/or its affiliates. All rights reserved.
+Licensed under the Universal Permissive License v 1.0 
+as shown at http://oss.oracle.com/licenses/upl
+*/
 
 /*
  DESCRIPTION
- The code sample connects to the Oracle Database and creates a table 'todoitem'.
+ The code sample connects to the Oracle Database and creates a table 'todoitem'. 
+ It inserts few records into this table and displays the list of tasks and task completion status. 
  Edit this file and update the connection URL along with the database username and password
  that point to your database. 
 
@@ -27,18 +31,19 @@ public class QuickStart {
  // Change this URL to match your target Oracle database (XE or else)
  final static String DB_URL="jdbc:oracle:thin:@//localhost:1521/XEPDB1";
  // Enter the database user 
- final static String DB_USER = "jdbctest";
+ final static String DB_USER = "<db-user>";
  // Enter the database password 
- final static String DB_PASSWORD = "jdbctest";
+ final static String DB_PASSWORD = "<db-password>";
  final static String CONN_FACTORY_CLASS_NAME="oracle.jdbc.pool.OracleDataSource";
 
  /*
- * The sample demonstrates UCP as client side connection pool.
+ * The sample creates a table 'todoitem' that lists tasks and task completion status. 
+ * Requirement: database connection string, database user and database password 
  */
  public static void main(String args[]) throws Exception {
+ 
  // Get the PoolDataSource for UCP
  PoolDataSource pds = PoolDataSourceFactory.getPoolDataSource();
-
  // Set the connection factory 
  pds.setConnectionFactoryClassName(CONN_FACTORY_CLASS_NAME);
  pds.setURL(DB_URL);
@@ -59,7 +64,6 @@ public static void main(String args[]) throws Exception {
  + pds.getAvailableConnectionsCount());
  System.out.println("Borrowed connections after checkout: "
  + pds.getBorrowedConnectionsCount());
- // Perform a database operation
  doSQLWork(conn);
  }
 
@@ -70,30 +74,30 @@ public static void main(String args[]) throws Exception {
  }
 
  /*
- * Creates a todoitem table and insert few rows, and select operations on
- * the new table created. Remove the table after verifying the data. 
+ * Creates a 'todoitem' table, insert few rows, and select the data from
+ * the table created. Remove the table after verifying the data. 
  */
  public static void doSQLWork(Connection conn) {
  try {
  conn.setAutoCommit(false);
- // Prepare a statement to execute the SQL Queries.
+ // Prepare a statement to execute the SQL Statement.
  Statement statement = conn.createStatement();
 
+ // Create a table 'todoitem' 
  String createSQL = "CREATE TABLE todoitem " 
  + "(id NUMBER GENERATED ALWAYS AS IDENTITY," 
  + " description VARCHAR2(4000), "
  + " creation_ts TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP,"
  + " done NUMBER(1, 0), PRIMARY KEY(id))";
- 
- // Create a table "todoitem"
+
  statement.executeUpdate(createSQL);
- System.out.println("New table todoitem is created");
+ System.out.println("New table 'todoitem' is created");
 
  //Insert sample data
  String[] description = { "Task 1", "Task 2", "Task 3", "Task 4", "Task 5" };
  int[] done = { 0, 0, 1, 0, 1 };
 
- // Insert some records into the table CUSTOMER
+ // Insert some records into the table 'todoitem'
  PreparedStatement prepStatement = conn.prepareStatement("INSERT INTO " 
  + " todoitem (description, done) VALUES(?, ?)");
  for(int row = 0; row < description.length; row++) {
@@ -103,9 +107,9 @@ public static void doSQLWork(Connection conn) {
  }
  prepStatement.executeBatch();
 
- System.out.println("Two records are inserted.");
+ System.out.println("New records are inserted");
 
- // Verify the table "todoitem"
+ // Verify the data from the table "todoitem"
  ResultSet resultSet = statement.executeQuery("SELECT DESCRIPTION, DONE FROM TODOITEM");
  System.out.println("\nNew table 'todoitem' contains:");
  System.out.println("DESCRIPTION" + "\t" + "DONE");