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Exception Class not found

I am trying to compile a program UCanAccess.java. I am getting the following exception when i run it. "java.lang.ClassNotFoundException: net.ucanaccess.jdbc.UcanaccessDriver".
I have copied all the UcanAccess jar files into the folder in which my java code is. Have made DSN. Can anybody tell me why i am getting this message.
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.sql.SQLException;
import java.sql.*;
public class UCanAccessExample {
public static void main(String args[]){
try {
String url = "jdbc:ucanaccess://c:/UCanAccess/Personinfo.accdb";
Class.forName("net.ucanaccess.jdbc.UcanaccessDriver");
Connection con = DriverManager.getConnection(url);
Statement st = con.createStatement();
String sql = "SELECT * FROM Person";
ResultSet rs = st.executeQuery(sql);
while(rs.next()){
String name = rs.getString("name");
String add = rs.getString("address");
String phone = rs.getString("phoneNum");
System.out.println(name + " " + add + " " + phone);
}
con.close();
} catch(Exception sqlEx){
System.out.println(sqlEx);
}
}
}
Image of folder in which my files are

You need to add UCanAccess driver in class-path.
Here are ways to do it.
java.exe -classpath E:\lib\* Main

JDBC programming

I am working in command prompt this is my code
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class JDBC {
static {
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException cnf) {
System.out.println("Driver could not be loaded: " + cnf);
}
}
public static void main(String[] args)
{
String connectionUrl = "jdbc:mysql://localhost:3306/mysql";
String dbUser = "root";
String dbPwd = "admin";
Connection conn;
ResultSet rs;
String queryString = "SELECT ID, NAME FROM exptable";
try {
conn = DriverManager.getConnection(connectionUrl, dbUser, dbPwd);
Statement stmt = conn.createStatement();
// INSERT A RECORD
stmt.executeUpdate("INSERT INTO exptable (name) VALUES (\"TINU K\")");
// SELECT ALL RECORDS FROM EXPTABLE
rs = stmt.executeQuery(queryString);
System.out.println("ID \tNAME");
System.out.println("============");
while (rs.next()) {
System.out.print(rs.getInt("id") + ".\t" + rs.getString("name"));
System.out.println();
}
if (conn != null) {
conn.close();
conn = null;
}
} catch (SQLException sqle) {
System.out.println("SQL Exception thrown: " + sqle);
}
}
}
i am getting error like
java.lang.ClassNotFoundException and java.sql.SQLException
so may i know what mistake have i made

You might have missed the classpath in your java command. While executing from command prompt you must mention the class path along with your command.
java -cp
ex:
java -cp /home/test/jars:/home/test/src com.test.Lab

Java Derby Creating User and "Schema Does Not Exist" Error

I am writing some archiving program in Java using derby DB. My program and DB connections (creating table, inserting and selecting data etc.) working fine when i use default user "APP" of Derby now.
When i try add some users and changing DB Properties, i can't connect to Database. I am sharing my User Creating and Changing DB Properties class below;
Creating user and Setting DB Properties:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
public class CreateUser {
public static void main(String[] args) throws SQLException, ClassNotFoundException, InstantiationException, IllegalAccessException{
Class.forName("org.apache.derby.jdbc.EmbeddedDriver").newInstance();
String connectionUrl = "jdbc:derby:sampleDB;user=APP;password=APP";
Connection con = null;
Statement stmt = null;
con = DriverManager.getConnection(connectionUrl);
stmt = con.createStatement();
stmt.executeUpdate("CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY(" +
"'derby.connection.requireAuthentication', 'true')");
stmt.executeUpdate("CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY(" +
"'derby.authentication.provider', 'BUILTIN')");
stmt.executeUpdate("CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY(" +
"'derby.user.testuser', 'ajaxj3x9')");
stmt.executeUpdate("CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY(" +
"'derby.database.fullAccessUsers', 'testuser')");
stmt.executeUpdate("CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY(" +
"'derby.database.propertiesOnly', 'false')");
stmt.close();
con.close();
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");
}
}
}
After that when i use below statement to connect DB i receive java.sql.SQLSyntaxErrorException: Schema 'TESTUSER' does not exist error
java.sql.Statement stmt = null;
Class.forName("org.apache.derby.jdbc.EmbeddedDriver").newInstance();
String connectionUrl = "jdbc:derby:sampleDB;create=false;user=testuser;password=ajaxj3x9";
con = DriverManager.getConnection(connectionUrl);
stmt = con.createStatement();
Also i have tried CREATE SCHEMA AUTHORIZATION testuser after all creating and properties defined in CreateUser class (sure i have rollback first creation proccess before trying this and run same Creating process after adding this line) but when i try same statement i receive TESTTABLE Schema Not Exist error this time.

MySQL Netbeans Java ResultSet Failure

Hi I a have MySql installed with Netbeans and have been trying to use Java with MySQL, however I am running into an issue when I run it. My database is called "test" and my table is "task". The two columns I have are: "id", and "task" (and I realized that naming a variable the same as the table probably is not a good idea). I also have a side question in the code area asking what it does. This is the error:
run:
May 22, 2015 11:52:25 PM databasetest.DatabaseTest main
SEVERE: Operation not allowed after ResultSet closed
java.sql.SQLException: Operation not allowed after ResultSet closed
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1074)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:988)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:974)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:919)
at com.mysql.jdbc.ResultSetImpl.checkClosed(ResultSetImpl.java:804)
at com.mysql.jdbc.ResultSetImpl.next(ResultSetImpl.java:6986)
at databasetest.DatabaseTest.main(DatabaseTest.java:43)
BUILD SUCCESSFUL (total time: 41 seconds)
This is my code:
package databasetest;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.logging.Level;
import java.util.logging.Logger;
public class DatabaseTest {
public static void main(String[] args) {
Connection con = null;
Statement st = null;
ResultSet rs = null;
PreparedStatement pst = null;
String url = "jdbc:mysql://localhost:3306/test";
String user = "root";
String password = "cinder";
try {
String author = "Trygve Gulbranssen";
con = DriverManager.getConnection(url, user, password);
st = con.createStatement();
rs = st.executeQuery("SELECT VERSION()");
//^^ what is VERSION? What is this supposed to be doing?
for (int i=1; i<=1000; i++) {
String query;
query = "INSERT INTO task(task) VALUES(" + 2*i + ")";
st.executeUpdate(query);
}
if (rs.next()) {
System.out.println(rs.getString(1));
}
} catch (SQLException ex) {
Logger lgr = Logger.getLogger(DatabaseTest.class.getName());
lgr.log(Level.SEVERE, ex.getMessage(), ex);
} finally {
try {
if (rs != null) {
rs.close();
}
if (st != null) {
st.close();
}
if (con != null) {
con.close();
}
} catch (SQLException ex) {
Logger lgr = Logger.getLogger(DatabaseTest.class.getName());
lgr.log(Level.WARNING, ex.getMessage(), ex);
}
}
}
}

SELECT VERSION() is meant to tell you your MySQL version. First, print the result of the SELECT then run your other queries. Running intermediate insert queries with the Statement implicitly closes the ResultSet, hence your error. Move
if (rs.next()) {
System.out.println(rs.getString(1));
}
before you run
for (int i=1; i<=1000; i++) {
// String query;
String query = "INSERT INTO task(task) VALUES(" + 2*i + ")";
st.executeUpdate(query);
}

java.sql.SQLException: No suitable driver found

I am trying to execute simple query using below DbQuery.java class which uses DbConnector to get a Connection from DriverManager.
note:
I have already included "mysql-connector-java-5.1.25-bin.jar" on my
classpath via: export
CLASSPATH=$CLASSPATH:/home/me/ocpjp/chapter-10/mysql-connector-java-5.1.25/mysql-connector-java-5.1.25-bin.jar
I am able to connect to mysql with "mysql -uroot -ptcial
addressBook", if it matters.
have also tried running with '-cp'
argument with no avail.
I am able to get my #3 DbConnect.java class to say "Database connection established".
Also #4 DbQueryWorking.java has no issues and provides expected output .
Can you please help me understand what is the issue here ?
1) DbConnector.java
package com.me.ocpjp.chapter10;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class DbConnector{
public static Connection connectToDb() throws SQLException{
String url = "jdbc:mysql//localhost:3306/";
String db = "addressBook";
String username = "root";
String password = "tcial";
return DriverManager.getConnection(url+db, username, password);
}
}
2) DbQuery.java
package com.me.ocpjp.chapter10;
import java.sql.Connection ;
import java.sql.Statement ;
import java.sql.ResultSet ;
import java.sql.SQLException ;
import com.me.ocpjp.chapter10.DbConnector;
public class DbQuery{
public static void main(String[] args){
try(Connection connection = DbConnector.connectToDb();
Statement statement = connection.createStatement();
ResultSet resultSet = statement.executeQuery("select * from contact")){
System.out.println("ID \tfName \tlName \temail \t\tphoneNo");
while(resultSet.next()){
System.out.println(resultSet.getInt("id") + "\t"
+ resultSet.getString("firstName") + "\t"
+ resultSet.getString("lastName") + "\t"
+ resultSet.getString("email") + "\t"
+ resultSet.getString("phoneNo") );
}
}catch(SQLException sqle){
sqle.printStackTrace();
System.exit(-1);
}
}
}
3) DbConnect.java
package com.me.ocpjp.chapter10;
import java.sql.Connection;
import java.sql.DriverManager;
public class DbConnect{
public static void main(String[] args){
String url = "jdbc:mysql://localhost:3306/";
String database = "addressBook";
String userName = "root";
String password = "tcial";
try(Connection connection = DriverManager.getConnection(url+database, userName, password)){
System.out.println("Database connection established");
}catch(Exception e){
System.out.println("Database connectioni NOT established");
e.printStackTrace();
}
}
}
4) DbQueryWorking.java
package com.me.ocpjp.chapter10;
import java.sql.Connection ;
import java.sql.Statement ;
import java.sql.ResultSet ;
import java.sql.SQLException ;
import java.sql.DriverManager;
public class DbQuery{
public static void main(String[] args){
String url = "jdbc:mysql://localhost:3306/";
String database = "addressBook";
String userName = "root";
String password = "tcial";
try(Connection connection = DriverManager.getConnection(url + database, userName, password);
Statement statement = connection.createStatement();
ResultSet resultSet = statement.executeQuery("select * from contact")){
System.out.println("ID \tfName \tlName \temail \t\tphoneNo");
while(resultSet.next()){
System.out.println(resultSet.getInt("id") + "\t"
+ resultSet.getString("firstName") + "\t"
+ resultSet.getString("lastName") + "\t"
+ resultSet.getString("email") + "\t"
+ resultSet.getString("phoneNo") );
}
}catch(SQLException sqle){
sqle.printStackTrace();
System.exit(-1);
}
}
}

it looks like that the URL in DbConnector.java is wrong. A colon is missing. The url must be:
jdbc:mysql://localhost:3306/
and not
jdbc:mysql//localhost:3306/

your URL is wrong, you're missing a colon in it, it should be:
String url = "jdbc:mysql://localhost:3306/";