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POJDBC : Unable to connect second time
 

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    <p>Hi All I am trying to connect a data base. below i have given the code. I am able to connect to data base but unable to connect 2nd time if difference between 1st time and 2nd time is greater then "wait time out" of mysql data base. I am using mysql data base. I am getting "Communications link failure" problem wait_timeout is 10 sec (for convenience) it is 8 hour for my DB I am giving you code </p> <pre><code>public class DatabaseManager { private static Connection jConn; private static DatabaseManager manager; public Boolean getUser(){ Statement jStmt = null; ResultSet rs = null; try { String query = "SELECT * FROM USER "; System.out.println(query); jStmt = jConn.createStatement(); rs = jStmt.executeQuery(query); while (rs.next()) { } }catch (Exception e) { e.printStackTrace(); return false; } return true; } public static synchronized DatabaseManager getInstance() { if (manager == null) { try { manager = initialize(); } catch (DatabaseInitializationException e) { // e.printStackTrace(); // throw new RuntimeException("Database Initialization // Exception"); } } return manager; } private static DatabaseManager initialize() throws DatabaseInitializationException { try { Class.forName(serverSrv.readPropertyValue("Srver_Path", "DBdriver")); } catch (ClassNotFoundException e) { throw new DatabaseInitializationException(e.getMessage()); } try { jConn = DriverManager.getConnection("DB_URL","user","password"); System.out.println("Excecuted initialize() for Database "); } catch (SQLException e) { throw new DatabaseInitializationException(e.getMessage()); } return new DatabaseManager(); } } </code></pre> <p>AND I am testing like</p> <pre><code> public static void main(String[] args) { long st = System.currentTimeMillis(); long end ; DatabaseManager dm = DatabaseManager.getInstance(); if( dm.getUser() ) System.out.println("success"); else System.out.println("failed.."); do{ end = System.currentTimeMillis(); }while( (end-st)&lt;12*1000 ); if( dm.getUser() ) System.out.println("success"); else System.out.println("failed.."); } </code></pre> <p>and it is giving exception like </p> <pre><code>com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure Last packet sent to the server was 0 ms ago. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074) at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2873) at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2763) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3299) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1837) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1961) at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2537) at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2466) at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1383) at mypackage.db.DatabaseManager.getUser(DatabaseManager.java:127) at mypackage.test.Test.main(Test.java:23) Caused by: java.net.SocketException: Software caused connection abort: recv failed at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.read(Unknown Source) at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:113) at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:160) at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:188) at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:2329) at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2774) </code></pre>
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    1. USuser531260
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    1. CO"Srver_Path" -> is that a typo?
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      1. USJigar Joshi
 

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