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copied!<p>If your app will works with many connections it's preferred to use pool of connections. It's already realized in Java and you may easily use it. This example of using pool in web app that uses tomcat(if you writing web-app you also can use tomcat's pool, and it would be better)</p> <pre><code>package usepool; import org.apache.tomcat.jdbc.pool.DataSource; import org.apache.tomcat.jdbc.pool.PoolProperties; /** * * @author brainless */ public class ConnectionPool { private static DataSource datasource; public static String dbURL = "jdbc:mysql://localhost:3306/" + "<YourDataBase>?useUnicode=true&useEncoding=true&characterEncoding=UTF-8"; public static String driverClass = "com.mysql.jdbc.Driver"; public static String userName = "root"; public static String password = "password"; public static boolean jmx = true; public static boolean testIdle = false; public static boolean testBorrow = true; public static boolean testReturn = false; public static int validationInterval = 30000; public static int timeBetweenEviction = 30000; public static int maxActive = 100; public static int initialSize = 10; public static int maxWait = 10000; public static int removeAbandonedTimeout = 60; public static int minEvictableIdle = 30000; public static int minIdle = 10; public static boolean logAbandoned = true; public static boolean removeAbandoned = true; public static String jdbcInterceptors = "org.apache.tomcat.jdbc.pool.interceptor.ConnectionState;" + "org.apache.tomcat.jdbc.pool.interceptor.StatementFinalizer"; private ConnectionPool() { } public static synchronized DataSource getInstance() { if (datasource == null) { PoolProperties p = new PoolProperties(); p.setUrl(dbURL); p.setDriverClassName(driverClass); p.setUsername(userName); p.setPassword(password); p.setJmxEnabled(jmx); p.setTestWhileIdle(testIdle); p.setTestOnBorrow(testBorrow); p.setTestOnReturn(testReturn); p.setValidationInterval(validationInterval); p.setTimeBetweenEvictionRunsMillis(timeBetweenEviction); p.setMaxActive(maxActive); p.setInitialSize(initialSize); p.setMaxWait(maxWait); p.setRemoveAbandonedTimeout(removeAbandonedTimeout); p.setMinEvictableIdleTimeMillis(minEvictableIdle); p.setMinIdle(minIdle); p.setLogAbandoned(logAbandoned); p.setRemoveAbandoned(removeAbandoned); p.setJdbcInterceptors(jdbcInterceptors); datasource = new DataSource(); datasource.setPoolProperties(p); } return datasource; } public static synchronized void closePool() { if (datasource != null) { datasource.close(); } } </code></pre> <p>}</p> <p>This class is singleton. To get connection in your code you need to use something like this</p> <pre><code>import usepool.ConnectionPool; /* * code */ connect = ConnectionPool.getInstance().getConnection(); </code></pre>

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