/* WwdClientExample.java
** This sample program is described in the Getting Started With Derby Manual
Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements. See the NOTICE file
distributed with this work for additional information
regarding copyright ownership. The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied. See the License for the
specific language governing permissions and limitations
under the License.
*/
// ## INITIALIZATION SECTION ##
// Include the java SQL classes
import java.sql.*;
public class WwdClientExample
{
public static void main(String[] args)
{
// ## DEFINE VARIABLES SECTION ##
// define the driver to use
String driver = "org.apache.derby.jdbc.ClientDriver";
// the database name
String dbName="jdbcDemoDB";
// define the Derby connection URL to use
String connectionURL = "jdbc:derby://localhost:1527/" + dbName + ";create=true";
Connection conn = null;
Statement s;
PreparedStatement psInsert;
ResultSet myWishes;
String printLine = " __________________________________________________";
String createString = "CREATE TABLE WISH_LIST "
+ "(WISH_ID INT NOT NULL GENERATED ALWAYS AS IDENTITY "
+ " CONSTRAINT WISH_PK PRIMARY KEY, "
+ " ENTRY_DATE TIMESTAMP DEFAULT CURRENT_TIMESTAMP, "
+ " WISH_ITEM VARCHAR(32) NOT NULL) " ;
String answer;
// Beginning of JDBC code sections
// ## LOAD DRIVER SECTION ##
try {
/*
** Load the Derby driver.
** When the embedded Driver is used this action start the Derby engine.
** Catch an error and suggest a CLASSPATH problem
*/
Class.forName(driver);
System.out.println(driver + " loaded. ");
} catch(java.lang.ClassNotFoundException e) {
System.err.print("ClassNotFoundException: ");
System.err.println(e.getMessage());
System.out.println("\n >>> Please check your CLASSPATH variable <<<\n");
}
// Beginning of Primary DB access section
// ## BOOT DATABASE SECTION ##
try {
// Create (if needed) and connect to the database
conn = DriverManager.getConnection(connectionURL);
System.out.println("Connected to database " + dbName);
// ## INITIAL SQL SECTION ##
// Create a statement to issue simple commands.
s = conn.createStatement();
// Call utility method to check if table exists.
// Create the table if needed
if (! WwdUtils.wwdChk4Table(conn))
{
System.out.println (" . . . . creating table WISH_LIST");
s.execute(createString);
}
// Prepare the insert statement to use
psInsert = conn.prepareStatement("insert into WISH_LIST(WISH_ITEM) values (?)");
// ## ADD / DISPLAY RECORD SECTION ##
// The Add-Record Loop - continues until 'exit' is entered
do {
// Call utility method to ask user for input
answer = WwdUtils.getWishItem();
// Check if it is time to EXIT, if not insert the data
if (! answer.equals("exit"))
{
//Insert the text entered into the WISH_ITEM table
psInsert.setString(1,answer);
psInsert.executeUpdate();
// Select all records in the WISH_LIST table
myWishes = s.executeQuery("select ENTRY_DATE, WISH_ITEM from WISH_LIST order by ENTRY_DATE");
// Loop through the ResultSet and print the data
System.out.println(printLine);
while (myWishes.next())
{
System.out.println("On " + myWishes.getTimestamp(1) + " I wished for " + myWishes.getString(2));
}
System.out.println(printLine);
// Close the resultSet
myWishes.close();
} // END of IF block
// Check if it is time to EXIT, if so end the loop
} while (! answer.equals("exit")) ; // End of do-while loop
// Release the resources (clean up )
psInsert.close();
s.close();
conn.close();
System.out.println("Closed connection");
// ## DATABASE SHUTDOWN SECTION ##
/*** In embedded mode, an application should shut down Derby.
Shutdown throws the XJ015 exception to confirm success. ***/
if (driver.equals("org.apache.derby.jdbc.EmbeddedDriver")) {
boolean gotSQLExc = false;
try {
DriverManager.getConnection("jdbc:derby:;shutdown=true");
} catch (SQLException se) {
if ( se.getSQLState().equals("XJ015") ) {
gotSQLExc = true;
}
}
if (!gotSQLExc) {
System.out.println("Database did not shut down normally");
} else {
System.out.println("Database shut down normally");
}
}
// Beginning of the primary catch block: uses errorPrint method
} catch (Throwable e) {
/* Catch all exceptions and pass them to
** the exception reporting method */
System.out.println(" . . . exception thrown:");
errorPrint(e);
}
System.out.println("Getting Started With Derby JDBC program ending.");
}
// ## DERBY EXCEPTION REPORTING CLASSES ##
/*** Exception reporting methods
** with special handling of SQLExceptions
***/
static void errorPrint(Throwable e) {
if (e instanceof SQLException)
SQLExceptionPrint((SQLException)e);
else {
System.out.println("A non SQL error occured.");
e.printStackTrace();
}
} // END errorPrint
// Iterates through a stack of SQLExceptions
static void SQLExceptionPrint(SQLException sqle) {
while (sqle != null) {
System.out.println("\n---SQLException Caught---\n");
System.out.println("SQLState: " + (sqle).getSQLState());
System.out.println("Severity: " + (sqle).getErrorCode());
System.out.println("Message: " + (sqle).getMessage());
sqle.printStackTrace();
sqle = sqle.getNextException();
}
} // END SQLExceptionPrint
}