We Keep Coding

JDBC SQL Server errors: ClassNotFound & Not Suitable Driver Found

I am very new to Java and am simply trying to connect to my MSSQL database and return a list of customers. When I try the JDBC connection, I get a "no suitable driver found" error. When I add a Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver") statement, I get a ClassNotFound error. This seems like it should be a lot easier than it's turning out to be. Please help me either find a suitable driver or how to get access through the Class.forName usage.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.ResultSet;
import java.sql.Statement;
public class DbConn {
public static String getConnString(){
return "jdbc:sqlserver://localhost\\SQLEXPRESS:1433;database=OhHold;";
}
public static void getConnection() {
try
{
//Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
String user = "<USER>";
String pw = "****************";
Connection connection = DriverManager.getConnection(getConnString(), user, pw);
Statement statement = connection.createStatement();
String sql = "select txtCompanyName as company from tblCustomers where intNotActive <> 1";
ResultSet result = statement.executeQuery(sql);
while (result.next()) {
System.out.println(result.getString(1));
}
}
/*
// Handle any errors that may have occurred.
catch (ClassNotFoundException e) {
e.printStackTrace();
}
*/
catch (SQLException ex) {
ex.printStackTrace();
}
}
public static void main(String[] args) {
getConnection();
}
}

Getting values from table in DB2

I want to get the values from a table using db2 and print out the results.
This is the code I am trying to use to do that:
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.SQLException;
public class connection {
public static void main(String[] argv) {
try {
Class.forName("COM.ibm.db2.jdbc.app.DB2Driver");
}
catch (ClassNotFoundException e) {
System.out.println("Please include Classpath Where your DB2 Driver is located");
e.printStackTrace();
return;
}
System.out.println("DB2 driver is loaded successfully");
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rset=null;
boolean found=false;
try {
conn = DriverManager.getConnection("jdbc:db2:sabarish","db2admin","Murugasaranam");
if (conn != null)
{
System.out.println("DB2 Database Connected");
}
else
{
System.out.println("Db2 connection Failed ");
}
pstmt=conn.prepareStatement("SELECT * FROM SYSCAT.COLUMNS WHERE TABSCHEMA= 'STD' AND TABNAME= 'inventory'");
rset=pstmt.executeQuery();
if(rset!=null)
{
while(rset.next())
{
found=true;
System.out.println("Class Code: "+rset.getString("clcode"));
System.out.println("Name: "+rset.getString("name"));
}
}
if (found ==false)
{
System.out.println("No Information Found");
}
} catch (SQLException e) {
System.out.println("DB2 Database connection Failed");
e.printStackTrace();
return;
}
}
}
It only prints out column names. Instead of column names, what query statement can I use to get the results? db2 select * from store.inventory
does not seem to work as well.

Try select * from STD.inventory

Is this can be the simplest way of executing queries in JDBC (JAVA) [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
This question does not appear to be about programming within the scope defined in the help center.
Closed 7 years ago.
Improve this question
In the process of learning of JDBC , I created below interface and classes for easy programming in future use . I believe still there is a possibility of doing simpler than this . What's my program does is getting results by giving Query String instead of doing all procedures like loading driver class, creating Connection and Statement objects and getting results from them. Will there be any simpler way of doing this and enhance the features in future ??
MyConnection.java ---- Interface
package com.cherukuri.jdbc;
import com.mysql.jdbc.Connection;
import com.mysql.jdbc.Statement;
public interface MyConnection {
public static String DRIVER = "com.mysql.jdbc.Driver";
public static String DB_URL = "jdbc:mysql://localhost:3305/STUDENTS";
public static String USER = "root";
public static String PASSWORD = “********";
default void loadDriver() {
try {
Class.forName(DRIVER);
} catch (ClassNotFoundException e) {
System.out.println(e.getMessage());
e.printStackTrace();
}
}
public Connection getConnection();
public Statement getStatement();
}
DataBaseConnection.java
package com.cherukuri.jdbc;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import com.mysql.jdbc.Connection;
import com.mysql.jdbc.Statement;
public class DataBaseConnection implements MyConnection {
Connection connection = null;
Statement statement = null;
#Override
public Connection getConnection() {
try {
connection = (Connection) DriverManager.getConnection(DB_URL, USER,
PASSWORD);
} catch (SQLException e) {
System.out.println(e.getMessage());
e.printStackTrace();
}
return connection;
}
#Override
public Statement getStatement() {
connection = getConnection();
try {
statement = (Statement) connection.createStatement();
} catch (SQLException e) {
System.out.println(e.getMessage());
e.printStackTrace();
}
return statement;
}
public ResultSet runQuery(String Query) {
ResultSet resultSet = null;
statement = getStatement();
try {
resultSet = statement.executeQuery(Query);
} catch (SQLException e) {
System.out.println(e.getMessage());
e.printStackTrace();
}
return resultSet;
}
}
TestBaseConnection.java
package com.cherukuri.jdbc;
import java.sql.ResultSet;
import java.sql.SQLException;
public class TestDataBaseConnection {
public static void main(String[] args) {
DataBaseConnection dbcon = new DataBaseConnection();
ResultSet rs = dbcon.runQuery("Select * from tblStudent");
try {
while (rs.next()) {
System.out.println(rs.getInt(1) + " ------------------- "
+ rs.getString(2));
}
} catch (SQLException e) {
e.printStackTrace();
}
}
}

You can try Spring JDBC which simplifies JDBC access in a way similar to your wrapper classes. It removes the need for some bolierplate code and manages the database connection for you.

How do I call variables from a Java class into another Class?

I've read about inheritance or using the import. I just simply am unable to get the right answer. Firstly my code is of the following form:
class queries{
String query1="Select * from "+tableName+";
String query2="Select "+columnName+" from "+tableName+";
}
Now, I have another class where I wish to make make SQL queries using the queries mentioned in the queries class:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
class test{
public static void main(String args[])throws SQLException
{
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
System.out.println("This is Wrong");
// TODO Auto-generated catch block
e.printStackTrace();
}
Connection connect = DriverManager
.getConnection("SQLCONNECTION");
PreparedStatement preparedStatement = connect
.prepareStatement(THIS SHOULD CALL query1 or query2);
ResultSet resultSet = preparedStatement.executeQuery();
while (resultSet.next()) {
System.out.println("THIS RUNS");
//display text
}
preparedStatement.close();
connect.close();
}
}
So well, I need to figure out how to call query1 or query2 from the queries class in test. Sorry, but I hope someone can help me how to do this in a clean way. I can also create a Hashtable in queries where I call the respective query based on its name.
Thanks a lot.

class queries
{
public static String getQuery1(String tableName)
{
return "Select * from "+tableName;
}
public static String getQuery2(String tableName, String columnName)
{
return "Select "+columnName+" from "+tableName;
}
}
Then do this:
PreparedStatement preparedStatement =
connect.prepareStatement(queries.getQuery1("INSERT TABLE NAME HERE"));

Connection using ConnectionPoolDataSource

To connect my required Database. I am planning to use ConnectionPoolDataSource class. But How can i set the details regarding the database name(to which i want it to be connected) on using this instance. Please Help on this occassion.

Try to read this documentation and example
EDIT
just modified example from above links
prepared steps:
- download MySQL Server
- download mySQL java driver
- download Apache Commons Pool
- download Commons DBCP
- Open MySQL Client like MySQL Workbench and create DB using next script
delimiter $$
CREATE DATABASE `test_stackoverflow` /*!40100 DEFAULT CHARACTER SET utf8 */$$
delimiter $$
CREATE TABLE `test_table` (
`idtest_table` int(11) NOT NULL,
`test_field` varchar(45) DEFAULT NULL,
PRIMARY KEY (`idtest_table`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8$$
INSERT INTO `test_stackoverflow`.`test_table` (`idtest_table`, `test_field`) VALUES (1, 'test1');
INSERT INTO `test_stackoverflow`.`test_table` (`idtest_table`, `test_field`) VALUES (2, 'test2');
create java project, add to class path , myscl connector, pool and dbcp (you just download all these jars)
add next classes
import org.apache.commons.dbcp.cpdsadapter.DriverAdapterCPDS;
import org.apache.commons.dbcp.datasources.SharedPoolDataSource;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;
/**
* #author Sergii.Zagriichuk
*/
public class Pool {
private static DataSource ds;
static {
DriverAdapterCPDS cpds = new DriverAdapterCPDS();
try {
cpds.setDriver("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
e.printStackTrace(); //To change body of catch statement use File | Settings | File Templates.
}
cpds.setUrl("jdbc:mysql://localhost:3306/test_stackoverflow");
cpds.setUser("root");
cpds.setPassword("root");
SharedPoolDataSource tds = new SharedPoolDataSource();
tds.setConnectionPoolDataSource(cpds);
tds.setMaxActive(10);
tds.setMaxWait(50);
ds = tds;
}
public static Connection getConnection() throws SQLException {
return ds.getConnection();
}
}
user name and pass should be changed to your db user/password
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class MainClass {
public static void main(String[] args) {
Connection connection = null;
Statement statement = null;
ResultSet resultSet = null;
try {
connection = Pool.getConnection();
// Do work with connection
statement = connection.createStatement();
String selectEmployeesSQL = "select * from test_table";
resultSet = statement.executeQuery(selectEmployeesSQL);
while (resultSet.next()) {
printTestTable(resultSet);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (resultSet != null) {
try {
resultSet.close();
} catch (SQLException e) {
} // nothing we can do
}
if (statement != null) {
try {
statement.close();
} catch (SQLException e) {
} // nothing we can do
}
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
} // nothing we can do
}
}
}
private static void printTestTable(ResultSet resultSet) throws SQLException {
System.out.print(resultSet.getInt("idtest_table")+", ");
System.out.print(resultSet.getString("test_field"));
}
}
Just run main method and you will see printed test values to console!!!

You could use an instance of DriverAdapterCPDS. This will need to add two libraries, Apache Commons Pool and Apache Commons DBCP. It is very useful when the driver you use does not include an implementation of connection pooling.
You can find a example in http://massapi.com/class/dr/DriverAdapterCPDS.html