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POJDBC Connection Issue
 

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    <p>I have create a getDBConnection method in my Java application. This returns a connection object, and hence I haven't closed this connection in this method itself. </p> <p>Now, I am invoking this method from various methods in my application at regular intervals, and closing them inside a try - finally block. I thought this should free up the connection after use. However, I am seeing a large number of connections opened (about 50) in the MySQL Administrator's Server Connections tab. </p> <pre><code>//Defining a method to retrieve a database connection // PropDemo is a properties class that retrieves Database related values from a file public Connection getDBConnection() { //Instantiating the Properties object PropDemo prop = new PropDemo(); Connection con = null; // Retrieving values from the parameters.properties file String JdbcDriver = prop.getMessage("JdbcDriver"); String JdbcUrlPrefix = prop.getMessage("JdbcUrlPrefix"); String DBIP = prop.getMessage("DBIP"); String DBName = prop.getMessage("DBName"); String DBUser = prop.getMessage("DBUser"); String DBPassword = prop.getMessage("DBPassword"); try { // Loading and instantiating the JDBC MySQL connector driver class Class.forName(JdbcDriver).newInstance(); con = DriverManager.getConnection(JdbcUrlPrefix + DBIP + "/" + DBName, DBUser, DBPassword); if (con.isClosed()) Logger.log("Connection cannot be established", "vm"); } catch (Exception e) { Logger.log("Exception: " + e, "vm"); Logger.log(Logger.stack2string(e), "vm"); } return con; } </code></pre> <p>I am also closing the associated ResultSet and Statement Objects. What could be missing here? </p> <p>I am planning to replace all the Statements with PreparedStatements for efficiency and security reasons. Will that help significantly? What else can be done?</p> <p>EDIT: This is just a core java application that is repeatedly quering for changes in some fields in a MySQL database through MySQL-JDBC connector. I am not using any framework like Spring or Hibernate. </p>
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    1. COcould you post your code?
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    2. COMore info is needed. What is your environment, is it an standalone application a framework, a JavaEE container? Do you use a connection pool?
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