COMPE 438 JAVA PROGRAMMING

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COMPE 438JAVA PROGRAMMING

• F. Cemile Serçe

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Java DataBase Connectivity(JDBC)
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JDBC

• The JDBC API is a Java API that can access any
  kind of tabular data
• JDBC helps you to write java applications that
  manage three programming activities
• Connect to a data source, like a database
• Send queries and update statements to the
  database
• Retrieve and process the results received from
  the database in answer to your query

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Example
Connection con DriverManager.getConnection
( "jdbcmyDrivermyDB,"myLogin","myPassw
ord") Statement stmt con.createStatement(
) ResultSet rs stmt.executeQuery("SELECT
a, b, c FROM Table1") while (rs.next())
int x rs.getInt("a") String s
rs.getString("b") float f rs.getFloat("c")

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JDBC Drivers

• JDBC consists of two parts
• JDBC API, a purely Java-based API
• JDBC Driver Manager,which communicates with
  vendor-specific drivers that perform the real
  communication with the database.

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JDBC Data Types
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7 Steps to use JDBC

• Load the driver
• Define the Connection URL
• Establish the Connection
• Create a Statement object
• Execute a query and
• Process the results
• Close the connection

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7 Steps to use JDBC(with example)

• Load the driver
• Before a connection to a database can be
  established, load the JDBC driver

try driverName sun.jdbc.odbc.JdbcOdbcDrive
r Class.forName(driverName) catch
(ClassNotFoundException e) // Could not find
the driver
try // Load the JDBC driver String (MySQL)
driverName "org.gjt.mm.mysql.Driver"
Class.forName(driverName) catch
(ClassNotFoundException e) // Could not find
the driver
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7 Steps to use JDBC(with example)

• Define the Connection URL
• jdbcsubprotocolsubname
• protocol name i.e. jdbc
• subprotocol represents the database you want to
  connect to e.g. mysql, oracle, odbc etc.
• subname provides additional information on how
  and where to connect

String DATABASE_URL "jdbcodbcphonebook"
String DATABASE_URL "jdbcmysql//localhost80/p
honebook"
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7 Steps to use JDBC(with example)

• Establish the Connection

String username admin" String password
sa" Connection connection DriverManager.getCo
nnection(DATABASE_URL, username, password)
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7 Steps to use JDBC(with example)

• Create a Statement object
• Statement object for invocation
• Statement stmt
• connection.createStatement()
• Execute a Query and 6. Process Results
• ResultSet object for result processing
• ResultSet rset stmt.executeQuery("SELECT
  address,script,type FROM worklist")
• Close the connection
• connection.close()

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7 Steps to use JDBC(with example)

• Create a Statement object
• Statement object for invocation
• Statement stmt
• connection.createStatement()
• Execute a Query and 6. Process Results
• ResultSet object for result processing
• ResultSet rset stmt.executeQuery("SELECT
  address,script,type FROM worklist")
• Close the connection
• connection.close()

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Online Resources
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Online Resources

• Suns JDBC Site
• http//java.sun.com/products/jdbc/
• JDBC Tutorial
• http//java.sun.com/docs/books/tutorial/jdbc/
• List of Available JDBC Drivers
• http//industry.java.sun.com/products/jdbc/drivers
  /
• API for java.sql
• http//java.sun.com/j2se/1.4/docs/api/java/sql/pac
  kage-summary.html