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POJava MySQL Driver and ClassNotFoundException
 

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    <p>I am attempting to connect to a mysql database, with a connection url of:</p> <pre><code>jdbc:mysql://127.0.0.1:3306/test </code></pre> <p>I have downloaded the coorect Mysql driver to connect with the database, and have tried a multitude of approaches to set the driver, with each not working. So far I have tried placing the JAR file in the following places (and changing the PATH environment variable accordingly)</p> <pre><code>JRE/LIB/ JDK/LIB/ JRE/LIB/mysql-connector-java-5.1.21 JDK/LIB/mysql-connector-java-5.1.21 </code></pre> <p>The path for the JAR file has been its location + <code>mysql-connector-java-5.1.21-bin.jar</code></p> <p>Over the last 4+ hours I have read multiple questions and solutions on StackOverflow, as well as online tutorials about this issue, and none have solved the problem. </p> <p>I have been using the following code to attempt a connection</p> <pre><code>import java.sql.*; import java.util.Date; public class DatabaseHelper{ private Connection conn = null; private Statement statement = null; private PreparedStatement preparedStatement = null; private ResultSet resultSet = null; private String url = null; public DatabaseHelper(){ try{ Class.forName("com.mysql.jdbc.Driver"); conn = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/test"); System.out.println("Driver Loaded!"); }catch(SQLException e){ e.printStackTrace(); }catch(ClassNotFoundException e){ e.printStackTrace(); } } } </code></pre> <p>Stacktrace</p> <pre><code>java.lang.ClassNotFoundException: com.mysql.jdbc.Driver at java.net.URLClassLoader$1.run(URLClassLoader.java:366) at java.net.URLClassLoader$1.run(URLClassLoader.java:355) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:354) at java.lang.ClassLoader.loadClass(ClassLoader.java:423) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) at java.lang.ClassLoader.loadClass(ClassLoader.java:356) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:186) at DatabaseHelper.&lt;init&gt;(DatabaseHelper.java:28) at DatabaseTest.&lt;init&gt;(DatabaseTest.java:6) at DatabaseTest.main(DatabaseTest.java:14) </code></pre>
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    1. USJnanathan
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    1. COHow exactly are you executing the code? What environment and what command? That'll provide more insight into the classpath actually being used. By the way, declaring those DB resources as instance variables this way is absolutely a terribly bad idea. Don't do that. Note that this is unrelated to your concrete problem.
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      1. USBalusC
    2. COPut the connector jar file in your classpath. The jdk and jre lib folders are not good places for your classpath. Create a folder under your root classpath (.) named lib and place it there. Then `java -cp .:./lib/mysql-connector-java-5.1.21.jar YourMainApp` should work. Placing other libs in the jre or jdk lib folders makes it hard to upgrade you Java version.
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      1. USkm1
    3. COYou should learn more about the classpath. http://vafer.org/blog/20081203024812/
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