Class newInstance Method

From Java Example Source Code

[edit] Overview - Class newInstance Method

This Java example program introduces Class newInstance method.

[edit] Java Source Code

• Package: example.sql.connection
• File: TestClassForNameNewInstanceApp.java

package example.sql.connection;
 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
 
public class TestClassForNameNewInstanceApp {
 
    public static void main(String args[]) {
 
	try {
	    Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();
	} catch (ClassNotFoundException e) {
	    System.out.println("Oops! Can't find class oracle.jdbc.driver.OracleDriver");
	    System.exit(1);
	} catch (IllegalAccessException e) {
	    System.out.println("Uh Oh! You can't load oracle.jdbc.driver.OracleDriver");
	    System.exit(2);
	} catch (InstantiationException e) {
	    System.out.println("Geez! Can't instantiate oracle.jdbc.driver.OracleDriver");
	    System.exit(3);
	}
 
	Connection conn = null;
	Statement stmt = null;
	ResultSet rset = null;
	try {
	    conn = DriverManager.getConnection("jdbc:oracle:thin:@dssw2k01:1521:orcl", "scott", "tiger");
 
	    stmt = conn.createStatement();
	    rset = stmt.executeQuery("select 'Hello '||USER||'!' result from dual");
	    while (rset.next())
		System.out.println(rset.getString(1));
	    rset.close();
	    rset = null;
	    stmt.close();
	    stmt = null;
	    conn.close();
	    conn = null;
	} catch (SQLException e) {
	    System.out.println("Darn! A SQL error: " + e.getMessage());
	} finally {
	    if (rset != null)
		try {
		    rset.close();
		} catch (SQLException ignore) {
		}
	    if (stmt != null)
		try {
		    stmt.close();
		} catch (SQLException ignore) {
		}
	    if (conn != null)
		try {
		    conn.close();
		} catch (SQLException ignore) {
		}
	}
    }
}

[edit] What Result You Can Get

Coming soon...

[edit] Required External Libraries and/or Files for this Java Example

In order to run this Java example, one of the following libraries may be required: In order to run this example program, one of the following libraries may be required:

• MySQL JDBC driver. You can download it from MySQL Connector/J — for connecting to MySQL from Java
• Oracle JDBC driver. You can download it from JDBC driver for Oracle.
• MSSQL JDBC driver. There are several vendors provide JDBC driver for MSSQL, you should chose one of them:
  • jTDS - SQL Server and Sybase JDBC driver. It is an open source JDBC 3.0 Type 4 driver for Microsoft SQL Server (6.5, 7.0, 2000 and 2005) and Sybase. jTDS is the fastest JDBC driver for MS SQL Server and is a complete implementation of the JDBC spec. You can download it from jTDS - SQL Server and Sybase JDBC driver
  • MSSQL JDBC driver from Microsoft.
    • JDBC driver for MSSQL 2000. You can download it from SQL Server 2000 Driver for JDBC Service Pack 3
    • JDBC driver for MSSQL 2005. You can download it from Microsoft SQL Server 2005 JDBC Driver 1.2
• PostgreSQL JDBC driver. You can download it from PostgreSQL JDBC driver. It is a pure Java (Type IV) implementation.
• HSQLDB JDBC Driver. HSQLDB is the leading SQL relational database engine written in Java. It has a JDBC driver and supports a rich subset of ANSI-92 SQL plus SQL 99 and 2003 enhancements. You can download it from hsqldb.

[edit] How to Run this Java Example Program

We recommend running this Java example program with Eclipse.

For assistance in working with Eclipse, please see How to Run Java Program with Eclipse.

It's fairly easy.

[edit] Question & Answer

Any question?

Click edit and post your question or answer here.