pool 3 « Connection « Java Database Q&A





1. connection, pool exhausted ???    coderanch.com

Hi, I am getting this error when I try to connect to the database : java.lang.Exception: Couldn't open connection to Public database: Cannot get a connection, pool exhausted at util.ConnectionDb.(ConnectionDb.java:39) at action.LogonAction.loginSP(LogonAction.java:79) at action.LogonAction.execute(LogonAction.java:57) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:419) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432) at javax.servlet.http.HttpServlet.service(HttpServlet.java:709) at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:368) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178) at ...

2. Problem in connection pooling    coderanch.com

3. Connection Pooling    coderanch.com

4. connection pooling    coderanch.com

Connection pooling uses the Java container to maintain the connection to the database. How the connection pooling is implemented is somewhat different from server to server. You will have to create a data source and register the driver in the container and tell the container how many connections to maintain. Then register the data source through JNDI. In your application code, ...

5. problem in connection pooling.    coderanch.com

Friends, I am facing a problem while connection pooling. The contents f web.cml file are jdbc/WroxTC5javax.sql.DataSourceForm the contents of server.xml file are

6. regarding connection pooling    coderanch.com

One way I would say, create a n(say 50 or something) number of connection objects and keep it in some queue(I mean some collection) objects. Then whenever the database connection needed by application, get the available connection object from that queue and use it. Once the need over just give back the object to the queue and make it free. So ...

8. Connection Pooling    coderanch.com

9. Connection pooling    coderanch.com

Can you explain more about your application and How do you find out that all 25 connections are in use? Usually we keep the connection pool size to let usual number of concurrent operation get a connection without waiting for a connection to be released. when all 25 connections are in use your database operation should wait until a connection get ...





10. Connection pool for XADataSource    coderanch.com

11. Connection Pooling implementation    coderanch.com

12. Connection pool    coderanch.com

13. cannot get connection, pool exhausted    coderanch.com

org.apache.tomcat.dbcp.dbcp.SQLNestedException: cannot get connection, pool exhausted. i have configured connection pooling in tomcat in the context.xml file. i have created a class with static method which will return the connection object from the datasource. Iam using this connection object every time for database transactions. At some time iam geeting this error.. org.apache.tomcat.dbcp.dbcp.SQLNestedException: cannot get connection, pool exhausted. here are the configuration ...

14. connection pooling    coderanch.com

maxActive - defines the maximum number of active connections the pool can contain. This is basically the absolute limit of the number of connections your pool is allowed to make to the database. maxIdle - defines the maximum number of idle connections that can exist in the pool. maxWait - how long a client can wait for a connection to become ...

15. DbConnectionBroker connection pool issue    coderanch.com

We have developed an application with the following architecture. 1) Windows NT 4.0 and Windows XP 2) Oracle 8.0 3) JDK 1.3.1_01 (Standard Edition), JSP, Servlet, Java IDL (CORBA). 4) Apache Web Server 1.3.20 5) Tomcat 3.2.2 6) DbConnectionBroker for connection pool 7) Thin Driver 8) Proprietary Application Server (DbConnectionBroker is a pure Java package for handling multiple concurrent database connections. ...

16. connection pooling    coderanch.com





17. connection pooling    coderanch.com

18. Is it possible to have connection to two different pools in the same method?    coderanch.com

Hello all, I am having trouble gaining connection to two different pools in the same method. I need to query two tables which reside in different data sources. The output from one query is the input for the second query. The second query gets executed for as many times as there are rows in the output of first query. I am ...

19. db connection pool manager    coderanch.com

20. Connection pool - check what blocks connections    coderanch.com

hi all, I have sometimes a problem with connections being blocked in pool. I use JBoss AS and Postgres, connection pool with standard params: max size 100, blocking timeout 30000ms. Usually I see that 0-5 connections are in use, but there are moments (once per few days, but as I keep getting more and more visitors it's more often now) when ...

21. Testing Connection Pooling    coderanch.com

22. Database Connection Pool Not Releasing Connection to pool    coderanch.com

I have a Class which performs JDBC calls on a DB2 Database The Database connections are pooled via the datasource, There is a method called getdbconnection() which obtains a pooled connection. The issue is that the method to obtain a connection and the method to release a connection are synchronized methods on the same object (DBConnectionPool). Therefore, at any given time, ...

23. Shared DB Connection Pool    coderanch.com

24. connection pool: difference between tables and views?    coderanch.com

I'm trying to solve an issue where I'm working with a Sybase database and Sun's app server. For reasons that are beyond my control, the java application looks at updateable views that map 1:1 to the database tables. The views aren't used to combine data from multiple tables, each view simply contains the identical data found in every corresponding table. I ...

25. Setting up a JDBC Connection Pool    coderanch.com

26. Connection pool    coderanch.com

27. Connection Pooling    coderanch.com

Am new to java. Am using data source in OC4J.. I have a query I heard Connection pooling reusing the connections. I have an application that gets a connection from datasource and executing a Query and then am closing a connection. How come the connection pool maintain this closed connection in a pool.. Forgive me if this question is foolish.. I ...

28. connection pooling    coderanch.com

29. Connection pool runs out of connections    coderanch.com

Hello, I started on writing my own connection pool, and I something is wrong. If i test my site with testing software it runs ok. But if I combine that with me clicking on random links in the website, I start loosing connections And eventually I run out of connection wich leads to null pointer exceptions. this is my code: static ...

30. Connection Pooling Problem    coderanch.com

Could someone please please help me with my connection pooling? I have been trying for a while now with no success. Below is my jsp file that I use for my database connection. I need someone to help me with the codes that will make this file implement connection pooling. Your help shall be very much appreciated. I have edited web.xml ...

31. Connection Pooling    coderanch.com

32. Constant Connection Pooling inside Jar?    coderanch.com

The goal of one project is to create a single jar that contains all of our data objects and sql commands for our 3 different databases and 4 webservice connections. This is going to be used in several applications - many of them rely on pieces of all three databases and some of the webservices. Our goal is to reduce all ...

33. using connection pooling for a standlone java application    coderanch.com

Hi, Is it possible to use connection pooling for DB2ConnectionPoolDataSource outside of a server? I am trying to use DB2ConnectionPoolDataSource in IBM universal driver(type 4) through a standalone application. I am not sure whether i can use it in an a standalone app or i need to have an application server to manage pooling. Regards, Giriraj.

34. Connection Pooling    coderanch.com

35. connection pooling problem    coderanch.com

I tried to do the connection pooling example given in JNDI Datasource HOW-TO webpage But I got the following error message in my log file Cannot create JDBC driver of class '' for connect URL 'null' java.sql.SQLException: No suitable driver at java.sql.DriverManager.getDriver(Unknown Source) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:773) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.getConnection(BasicDataSource.java:540) at foo.DBTest.init(DBTest.java:23) at org.apache.jsp.test_jsp._jspService(org.apache.jsp.test_jsp:51) at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97) at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:322) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264) ...

36. Weird problem when using connection pool    coderanch.com

I've encountered one problem when using weblogic connection pool by data source. I'm trying to use that connection to insert record but if using connection pool, when calling preparedStatementexecute(), it will throw unique constraint for PK of that table, although actually only insert 1 record. However if using direct jdbc connection, the record can be inserted. Is it due to some ...

37. Connection Pooling, anyone help me please!    coderanch.com

Hello guys... I'm having a bit of headache trying to figure out what's going on with my Connection Pooling since it's not working as it supposed to... it's been opening up to 150 connections for some reason which I don't know why... I've made it as simples as possible but the problem still remains. Could anyone give me a hand on ...

39. Connection pooling issue in Apache 6.0    coderanch.com

This code is working fine without connection pooling but when I am using connection pooling I am facing some problem .Please check the code once I have given comment. 1) Connection pool code in apache server public static Connection getConnection() throws SQLException { try { String jndiname="jdbc/min"; Context initContxt = new InitialContext(); DataSource ds = (DataSource) initContxt.lookup("java:/comp/env/"+jndiname); connection= ds.getConnection(); } catch(Exception ...

40. How can we deal if Users are exceeded to connection pool size    coderanch.com

One thing I can think of, reduce the scope to minimum in which the connections are used in the application (of course this is in the code level). But as with your statement if all 200 connections are in use at the same time then the next user will simple have to wait.

41. Connection Pooling Doubt    coderanch.com

Hi Ranchers, Have a doubt this time on JDBC Connection pooling. I have an application which connects to JDBC via a DSN named jdbc/FCRDSN created in Websphere App Server 5.1 and the connection timeout by default has been set to 180(seconds), the problem comes when this timeout reaches and my application throws a StaleConnectionException. I have browsed internet , however did ...

42. jdbc connection pooling    coderanch.com

Hi all, I have a situation where there are 3 applications , which are just components , I mean which do not run under any application server, So I need to create a component for all the 3 apps to use a connection pool, and all the 3 apps should use the connection pool component , I mean as one point ...

43. Connection pooling...?    coderanch.com

44. JDBC Connection Pooling    coderanch.com

45. implementing connection pool    coderanch.com

46. Connection Pooling java code    coderanch.com

47. JDBC Connection Pooling Framework    coderanch.com

I tried using the DBCP BasicDataSourceExample....as below: import javax.sql.DataSource; import org.apache.commons.dbcp.BasicDataSource; import java.sql.Connection; import java.sql.Statement; import java.sql.ResultSet; import java.sql.SQLException; /** * * @author user * */ public class BasicDataSourceExample { /** * * @param args */ public static void main(String[] args) { // First we set up the BasicDataSource. // Normally this would be handled auto-magically by // an external configuration, ...

49. static connections and connection pooling - what happens when physical connection is lost?    coderanch.com

public class MyEJB{ private Connnection mainConnection = null; private static final Connection staticConnection = (new ConnectionHelper()).getConnection(); public MyEJB(Connection conn){ this.mainConnection = conn; } public void myMethod(List myList){ //... for (int j = 0; j < myList.size; j++) { boolean valid = MyEJB.makeValid(); //... } } private static synchronized boolean makeValid(){ staticConnection.setAutoCommit(false); //... staticConnection.commit(); return true; } }

50. Connection pooling problem    coderanch.com

51. DB connection pooling    coderanch.com

Hi All, This will be a quick one.. I wanted to know, Lets assume I have 10 small java applications and they have their own Database configurations ( max wait, connection pooling settings, user id/pass, driver settings etc.... ) so my question is if all the 10 applications use the same database at the same time, will there be that many ...

52. Connection Pooling size    coderanch.com

Regarding connection pooling in data base ,i need clarification.. In production environment we will set the pool size as 10 to 50. What will be the connection pool size of a like some Popular banking application Or application like Popular JavaRanch . Or is there any other alternative technique for connection pooling mechanism.

53. Connection Pooling    coderanch.com

Connection Pooling, 1. when to use connection pooling. 2. On which factor the no. of connections parameter depend. example : To access my application by 2000 users we can define 20 connections. if the users increases to 10000 then how many connections we require to access my application. please clarify me on this.

54. Connection Pooling Help Needed    coderanch.com

I'm not sure why you would want to use connection pooling. Connection pooling is necessary in Java EE apps because of the nature of how web apps work (discreet requests made from possibly thousands of users). Having a database connection per user is not possible and having a connection pool thus allows the users, and requests, to share a finite resource ...

55. pooled connection object vs non pooled connection object    coderanch.com

Hello All, I have found my self in a bit confusion while reading database connection pooling topic. I have read about advantages of connection pooling, and how it Enhances performance etc. But a question raises suddenly in my mind , that what if I put non pooled connection object reference in servlet context and access that context when ever required. Means ...

56. Connection Pooling    coderanch.com

57. No of connection in Pool.    coderanch.com

Hi All, I congifured for connection pooling in tomcat and i am able to get the connections successfully and performing all the operation. But, i am not seeing any connection detail,(i.e) session created in DB for pooled connection using toad. Toad, always show only one ...

58. Dynamic Connection Pool    coderanch.com

I created a ConnectionPool for a Tomcat web application and it works great. I used the Singleton pattern. It measurably improved the performance of the application. But in our enterprise, we have several environments (test-dev-production) where we connect to different databases. Is there a way of making one ConnectionPool class that could serve different databases or named connection pools? It seems ...

59. Understanding Connection Pooling - a few problems    coderanch.com

Hi ! I am reading about connection pooling, and have seemingly understood why it is used. But I am not sure how it is used. This is a code I wrote after what I understood (manipulated some code i found on the internet): (I get the correct output for this program) import java.sql.*; import javax.sql.*; public class ConnectionPooling2 { public static ...

60. Connection Pooling Question    coderanch.com

Hello everyone, I understand the high level concept of connection pooling. What I'm trying to get is a more detailed understanding. In particular, suppose I were to write my own connection pool (in Java of course;) ) . I understand the notion of caching the connections. What i'm not getting is this: If I have code that calls the connection pooling ...

61. JDBC: connection pooling    coderanch.com

The JDBC API changed in big ways between version 1 and 2 so they require different caching strategies. One word of warning, the book you are reading was written over 10 years ago. The JDBC API alone has gone through 2 more major revisions. The Java API has had 4 major revisions.

62. A question about Connection pooling and authenicating clients    coderanch.com

I am thinking that as far as a DB Server is concerned , any connections in the pool are indeed open even though not actively working for any client and further that any client taking a connection from the pool must have already passed some type of authentication. In other words , are the connections in the pool all at the ...

63. Connection Pooling    coderanch.com

Most of the times the connection pool object would have this documented. Most of the time I suspect they wait put you in wait with some timeout. All of this is configurable. Most of the times the max required connection can be safely set. If not most connection pool allow you to set maxConnection to no limit. P.S - When I ...

64. Required details of Connection Pooling    coderanch.com

66. connection pooling    coderanch.com

please i am new to jsp, when i tried to implement this example of connection pooling it gives me (too many connections) error, and the connection doesn't work those are the two classes of the example please could any one tell me where is the problem and how to implement the in a right way ? thanks in advance ////////////////////////////class ConnectionPoo.javal ...

67. Connecting to more than one database in a connection pool    coderanch.com

Is it possible to connect to more than one database in the same connection pool object? Or do I need to create a connection pool object for each database I connect to? I'm using JSP/Servlets...so I was curious about how to go about this and how I would set up my context.xml file. My users are in a seperate database than ...

68. how to get the connection pool object    coderanch.com

Hello ALL, i have one problem in my appli.That is when multiple users accessing the appl at the same time, it is giving "ORA-01000: maximum open cursors exceeded".Is there any solution to overcome that problem.And one more thing i want to know is, is there any option to get the connection pool obj. Can anyone of you please help me out ...

69. Connection pooling with my own cofiguration file instead of Initial Context.    coderanch.com

Hi Java Ranch, I am working on a web application an i want to implement the Connection Pooling. And i wat to store my database details in a seperate properties file instead of placing them in Context.xml. I had done some modification to Connection Pool Class for getting details from configuration file. package com.dgsecure.db; import java.sql.*; import java.util.*; public class ConnectionPool ...

70. Regarding Connection pool    coderanch.com

Hi, The advantage of using connection pool is get the open connection......use it and return it to the pool once the request is processed so that other request acquires that connection and uses it. I have a doubt........... We generally acquire the connection and close it in finally like con.close() here does it mean that we are closing that acquired connection ...

71. connection pooling issue in production environment -    coderanch.com

Jan Cumps wrote:That lookup you do is to find a database connection pool that is configured somewhere (in your application sever maybe?) We are using oracle application server and I see there is a place where timeout settings can be set. Please see snapshot. Jan Cumps wrote:Can you show us the outline of how you get the connection, what you do ...

72. getting the active connections from connection pool    coderanch.com

Hi, >> Is there a way to get the active connections from the connection Pool. Did not get your question. DataSource.getConnection always returns an active connection if you are using Connection Pooling. You have to close the connection when using connection pool so that it is returned to the pool and can serve other components. You can do it in finally ...

73. How to Recreate Connection in the pool.    coderanch.com

Hi All, If we have Connection Pooling and DB server is restarted or all the connection in DB server is killed. How to recreate the connection in application connection pooling. for Example: I have started the application with Connection pooling, if the connection are killed in DB server, how can i refresh the Connection pooling. Thanks In Advance, Bennet Xavier X ...

74. Need guidance regarding connection pooling.    coderanch.com

Hi everybody, I am Chaitanya, I want to write my own connection pooling class where I want to create only 10 connection objects and return those when asked. I have worked around it to a little extent for a single connection object. import java.sql.*; class ConnectionPool { private static Connection con; private ConnectionPool(){} public static Connection getConneciton() { if(con==null) { try ...

75. connection pooling    coderanch.com

1st you need to configure Tomcat 5.5 with admin console. After configuring that Create a helper class. Use JNDI to look up the connection. Create a static method to get connection(the return type for which is Connection) I am providing you some part of the code public class DbUtil { private static DataSource dataSource; static { try { Context initCtx = ...

76. Connection Pooling    coderanch.com

We were running a performance testing, and bombarded the application server. Soon we ran into "Network adapter could not establish the connection" problem. After checking, I found the connection pool wasn't even configured, that meant the whole application was running without a connection pool! I was using Oracle Application Server and a native data source. Someone said the pooling was just ...

77. Regarding Connection Pool    coderanch.com

80. need help on Connection Pooling    coderanch.com

Hi, I'm developing a simple application. I'll like to implement the connection pooling in my application. When i searched the net i can able to see lot of examples but at end of the session i'm not able to understand even a single method.. Could any please explain me which is best and we can go for it..

81. using a connection from the pool.    coderanch.com

82. Connection Pool Refreshing    coderanch.com

83. Refreshing Connection pool    coderanch.com

Hi I am using Tomcat 6. Using the jndi concept the connection pool is used for my application. Driver used is thin driver. Everything this working fine, but how to implement the concept of connection release or refresh the connection pool after use. Is there any method which does that ? Please help Thank you.

84. ClassCastException with Connection Pooling    coderanch.com

ClassCastException with Connection Pooling ============================ This one may belong in Beginner's Java , however ... I'm following Gregg Lagnese "How to Setup Global Mapping for Oracle JDBC Connection Pooling with Tomcat") http://www.microdeveloper.com/html/JNDI_Orcl_Tomcat1p.html Thank you for any help. Environment : Apache-Tomcat 6.0.18 , Oracle XE 10.2.0 The JSP :

A.jsp

<% gbpackage.ConnectionPool cp = new gbpackage.ConnectionPool() ; cp.connect() ; %> Message = ...

85. Getting connection from pool?    coderanch.com

Assume that we get database connection from datasource pool in jdbc. If we dont close the connection that connection will be lying there as it is and consider as connection leak and will not return to pool. But if we close the connection that connection will move back to pool , Is this correct? Secone question is we always say connection ...

86. what connection pooling is better?    coderanch.com

87. Regaring connection pool    coderanch.com

88. Connection Pool    coderanch.com

89. JDBC Connection Pool behaviour    coderanch.com

90. connection pooling    java-forums.org

Hi, I have a web app running on jboss and oracle as database. My app is basically a reporting app where I have many sql queries being called to get result from db.I am using JDBC connection pool to get and return connection from the pool just before and after each query.There will be about 45-50 users accessing this application at ...

91. we implement connection pooling ourselves, but why it always out of connection ?    java-forums.org

10-20-2009 09:54 AM #1 zengqingyi12 Member Join Date Oct 2009 Posts 4 Rep Power 0 we implement connection pooling ourselves, but why it always out of connection ? Following is the source code: //public class ConnectionPool implements Runnable public class ConnectionPool { private static Logger loger_error = Logger.getLogger("error"); // JDBC Driver name String driverName; // JDBC Connection URL String ...

92. using snaq.db for connection pool    java-forums.org

Hi, I am using eclipse java to develop a mysql project. I try to use snaq.db (DBPool-5.0) to set up a db connection pool. But I got error when i run this statement like : ConnectionPool pool = new ConnectionPool("local", 1, 8, 30, 3000, url+dbName, userName, password); Can anyone give some hint how make this work? Thanks Li

94. Database connection pool    forums.oracle.com

95. DB Connection pool    forums.oracle.com

96. jdbc connection pool    forums.oracle.com

97. DATABASE CONNECTION POOLING    forums.oracle.com