Cannot connect to access database from jar file [duplicate] - java

This question already has an answer here:
Manipulating an Access database from Java without ODBC
(1 answer)
Closed 6 years ago.
I cannot connect to my access database using jdbc:ucanaccess driver.
Here the code:
public void open_conn()
{
try
{
Class.forName("net.ucanaccess.jdbc.UcanaccessDriver");
String url = "jdbc:ucanaccess://C:\\AnalysisLab\\dbanal.accdb";
conn = DriverManager.getConnection(url, "username", "password");
stmt = conn.createStatement();
}
catch (Exception e)
{
JOptionPane.showMessageDialog(null,"Error: "+e.getLocalizedMessage()); e.printStackTrace();
}
}
The error reported : "Error: net.ucanaccess.jdbc.UcanaccessDriver"
I tried including org-netbeans-modules-db-mysql.jar file in the jar directory, but it doesn't work.

This documentation says that your URL should be in the following format:
Connection conn=DriverManager.getConnection("jdbc:ucanaccess://",user, password);
// for example:
Connection conn=DriverManager.getConnection("jdbc:ucanaccess://c:/pippo.mdb");
So your URL is going to change to:
String url = "jdbc:ucanaccess://C:\\AnalysisLab\\dbanal.accdb";
And add the following jar files to your CLASSPATH as all of these are needed by the actual JDBC driver itself:
ucanaccess-3.0.3.jar
commons-lang-2.6.jar
commons-logging-1.1.1.jar
hsqldb.jar
jackcess-2.1.3.jar
As per your question, I assume that you are on Netbeans and hence you need to all these 5 jars there in the following manner:
Expand the tree view for your project, right-click the "Libraries" folder and choose "Add JAR/Folder...", then browse to the JAR file.
A very detailed explanation of a similar question can be found here.

Related

Why am I getting java.sql.SQLException: No suitable driver found when the url is correct and driver is present?

I am trying the following code to make connection with my database online, hosted on ElephantSQL.
private static Connection getConnection() {
try {
Class.forName("org.postgresql.Driver");
}
catch (ClassNotFoundException e) {
System.out.println("Jar not found "+e.getMessage());
}
//dbUrl is given this way
String dbUrl = "jdbc:postgres://database:password#manny.db.elephantsql.com:5432/database";
String username = "database";
String password = "password";
try {
return DriverManager.getConnection(dbUrl,username,password);
} catch (SQLException e) {
e.printStackTrace();
}
return null;
}
But I am getting the following error:
java.sql.SQLException: No suitable driver found for < url >
I tried all the things from the similar questions which I found here
Question 1
and
Question 2.
But nothing worked and I am stuck. I would appreciate any help.
As documented in the manual the URL for Postgres must be structured like this:
jdbc:postgresql://host:port/database
The prefix jdbc:postgres needs to be jdbc:postgresql and the part database:password#manny.db.elephantsql.com:5432 in your URL is wrong. It's hard to tell what exactly the hostname is, but I guess you need to use:
jdbc:postgresql://manny.db.elephantsql.com:5432/database
It seems that your driver jar file is not in classpath.
One of the option is put driver jar file in lib directory of your project and add jar file in classpath ( or buildpath in eclipse )
you can download dirver file from given URL
https://jdbc.postgresql.org/download.html

JDBC no suitable driver found just on Linux? [duplicate]

This question already has answers here:
Connect Java to a MySQL database
(14 answers)
The infamous java.sql.SQLException: No suitable driver found
(21 answers)
Closed last month.
I am trying to write a program to connect to a MySQL database in eclipse, but I get the error "java.sql.SQLException: No suitable driver found".
The java code is:
import java.sql.*;
public class FirstExample {
//static final String S_JDBC_DRIVER = "com.mysql.jdbc.Driver";
static final String S_DB_URL = "jdbc:mysql://localhost:3306/emp";
static final String S_USER = "root";
static final String S_PASS = "root";
public static void main(String[] args) {
try {
System.out.println("Connecting to database...");
//Class.forName(S_JDBC_DRIVER);
Connection connection = DriverManager.getConnection(S_DB_URL,
S_USER, S_PASS);
System.out.println("Creating statement...");
Statement statement = connection.createStatement();
String sql = "SELECT * FROM Employee";
ResultSet resultSet = statement.executeQuery(sql);
while (resultSet.next()) {
int iId = resultSet.getInt("id");
int iAge = resultSet.getInt("age");
String sFirst = resultSet.getString("fname");
String sLast = resultSet.getString("lname");
System.out.print("ID: " + iId);
System.out.print("\tAge: " + iAge);
System.out.print("\tFirst: " + sFirst);
System.out.println("\tLast: " + sLast);
}
resultSet.close();
statement.close();
connection.close();
} catch (SQLException se) {
for (Throwable t : se) {
t.printStackTrace();
}
}
System.out.println("Goodbye!");
}
}
The output in the console tab is:
Connecting to database...
java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost:3306/emp
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at FirstExample.main(FirstExample.java:21)
Goodbye!
I have used the MySQL Connector/J. It is unzipped in the MySQL installation directory and the jar file is added to the CLASSPATH.
Also refer to this image. There is an ! mark at the project root.image01
I get the error as in the next image: image02 when I include the 2 commented statements:
static final String S_JDBC_DRIVER = "com.mysql.jdbc.Driver";
Class.forName(S_JDBC_DRIVER);
For all but the most trivial applications the CLASSPATH environment variable is NOT used. Normally the libraries are include in the Class-Path entry in the manifest of the jar, or in the -cp option of the java commandline.
In this case you need to add the MySQL JDBC driver to the buildpath of your Eclipse project.
I had the same problem. I solved it by adding:
Class.forName("com.mysql.jdbc.Driver");
you can place the path like java -cppwd/mysql-connector-java-5.1.22-bin.jar:. <classname>.
make sure that your in same directory where the mysql driver is .
Hope that helps .
Load Driver class just before getting the connection.
Use this code:
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/test_db", "user", "passw");
Alternatively you can also add the installed jar file to your eclipse project by selecting the project in eclipse, right click it and go down to properties, select the Java Build Path>>select the Libraries Tab>>Add external jar file and browse for the installed mysql-connector-java.jar file or any mysql java connector file int the /usr/share/java/ directory for most ubuntu users. Click okay and rebuild your project. Good luck
I encountered the same problem as you, but I handled it as follows:
I copied the jar, which is called mysql-connector-java-5.1.23-bin.jar, into the \Apache Software Foundation\Tomcat 6.0\lib, and restarted tomcat.
Hope that helps

SQLite Exception Path does not exist

I am trying to connect an already existing SQLite database to my java project, as a temporary solution for testing a simple log-in dialog. Here is my connector class:
import java.sql.*;
import javax.swing.*;
public class SQLite_login_connector {
//Initializes global connection variable (unused until now!)
Connection conn_log = null;
public static Connection logindb_connection(){
//Simple try catch block that prints error trace log in a JOptionPane if runtime error occurs.
try{
Class.forName("org.sqlite.JDBC");
Connection conn_log = DriverManager.getConnection("jdbc:sqlite:/SQLite/ISRSMS_Login.sqlite");
JOptionPane.showMessageDialog(null, "Connection Successful!");
return conn_log;
} catch(Exception e){
JOptionPane.showMessageDialog(null, e);
return null;
}
}
}
My SQLite database is located in a folder within my project folder:
When I try running my connector class, it throws the following exception:
For me it looks as if it assumes that the folder which contains my database is located on my F: drive, as opposed to my root project in my local repository. I have tried putting the database into my src folder, as well as into a new resource folder all-together. Every time it throws the same exception. Why does it do that?
As you have metntioned / in yor connection string it is pointing to the root directory of your drive
Remove the / in your connection string Do as follows
DriverManager.getConnection("jdbc:sqlite:SQLite/ISRSMS_Login.sqlite")
For your convenience please follow the naming convention of java language
http://www.oracle.com/technetwork/java/codeconventions-135099.html
Why is your URL .sqllite? I would expect .db - like here
jdbc:sqlite:C:/mydir/mydb.db

Connecting to a mySQL database using Java

So I just started learning about databases this week and one of the things I need to be able to do is connect to my mySQL database that I created using Java. I have done some research and I have tried to find the correct way of doing this I just can't seem to figure out how. Here is my code:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class Menu
{
public void menu()
{
Connection conn;
String url = "jdbc:mysql://localhost:3306/";
String dbName = "gym";
String driver = "com.mysql.jdbc.Driver";
String userName = "root";
String password = "password";
try
{
Class.forName(driver).newInstance();
conn = DriverManager.getConnection(url+dbName,userName,password);
System.out.println("Connected to the database");
conn.close();
System.out.println("Disconnected from database");
}
catch (Exception e)
{
System.out.println("NO CONNECTION =(");
System.out.println(e.getMessage());
}
}
}
Now the problem is, is that every time I run this code, the "No Connection =( " appears and then it says the error is: "com.mysql.jdbc.Driver". Can somebody please help me and say what I am doing wrong? Thank you. Much appreciated.
Your error means that your library path doesn't contain the jar that contains the com.mysql.jdbc.Driver class.
You don't have to change anything in your code. If you are running it via Eclipse, you should add mysql-connector-java-x.x.x-bin.jar to your build path (where x.x.x is the version of the jar).
All JDBC connection classes need their respective drivers which are normally supplied as jar files from the database vendor, add the relevant database driver to your classpath.
The .jar file will be available from the vendors site, in this case : http://www.mysql.com/products/connector/ and then to add this to the classpath of your project in the ide of your choice. Here is a guide for eclipse : http://www.wikihow.com/Add-JARs-to-Project-Build-Paths-in-Eclipse-(Java)
Try and run again once you have this.

JDBC for SQLite in Netbeans: No suitable driver found

I need to load data from an SQLite file into a java program which I develop in Netbeans.
The file is to be loaded via a swing menu item. I'm using sqlitejdbc as driver.
Here are the code blocks I assume to be important:
// header stuff
package aufgabe_9;
import java.sql.*;
//...
// menu item opening the file
private void mitemOpenFileActionPerformed(java.awt.event.ActionEvent evt)
{
/**
* Handles the dialogue for selecting and loading file.
*/
JFileChooser fileChoose = new JFileChooser();
fileChoose.showOpenDialog(this); //'this' calls the current object
//Load the sql file
try {
String filePath = fileChoose.getSelectedFile().toString();
Connection conn = DriverManager.getConnection("jdbc:sqlite:" +
filePath);
//Close the connection
if (conn != null)
conn.close();
}
catch (SQLException e){System.err.println("Database problem: " + e);}
}
}
//...
When running the program and loading a file via the menu, I get the following error:
java.sql.SQLException: No suitable driver found for jdbc:sqlite:/home/levent
/temp/A9AProbeflaeche.db
After reading the respective stackexchange posts, I understand that this
problem can be caused by (1) a malformed file URL or (2) the driver not being
loaded. Here's some further information:
I added the sqlitejdbc-3.7.2.jar to the library classpath via Tools --> Libraries as well as to the project libraries via Window --> Projects.
I also checked the Classpath by using this function. It contains the path to the jdbc jar-file just as expected.
I can connect to the database via the Services menu without any problems, so I can assume the URL to be correct, as well as sqlite running on my system.
Some OS information: I'm running Netbeans 8.0 on 64 bit ARCH Linux 3.12.9-2.
Can anybody tell me what I'm missing here? Any help appreciated!
Problem solved
Here is the code that works for me:
//...
private void mitemOpenFileActionPerformed(java.awt.event.ActionEvent evt)
{
/**
* Handles the dialogue for selecting and loading file.
*/
JFileChooser fileChoose = new JFileChooser();
fileChoose.showOpenDialog(this);
//Load the sql file
try {
//Get file path
String filePath = fileChoose.getSelectedFile().toString();
//Open connection
Class.forName("org.sqlite.JDBC");
Connection conn = DriverManager.getConnection("jdbc:sqlite:" + filePath);
//Do stuff...
//Close the connection
conn.close();
}
//"Multicatch":
catch (SQLException | ClassNotFoundException e) {
System.err.println("Database problem: " + e);
}
//...
You probably need to load the driver class so that it registers itself to the DriverManager using the following code:
Class.forName("org.sqlite.JDBC");
Note: this only needs to be called once in your application.
This was a standard procedure before the Java included the ServiceLoader API, now the DriverManager uses that API to register the drivers it finds in the classpath, but the drivers need to declare a file named java.sql.Driver containing the name of the driver class in the directory META-INF\services of their jar.

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