<td>The connection username to be passed to our JDBC driver to establish a connection.
<td>The connection password to be passed to our JDBC driver to establish a connection.
<td>The connection URL to be passed to our JDBC driver to establish a connection.
<td>The fully qualified Java class name of the JDBC driver to be used.
<td>The connection properties that will be sent to our JDBC driver when establishing new connections.
<br/>Format of the string must be [propertyName=property;]*
<br/>NOTE - The "user" and "password" properties will be passed explicitly,
so they do not need to be included here.
Commons DBCP example source code file (configuration.xml)
The Commons DBCP configuration.xml source code
<?xml version="1.0" encoding="ISO-8859-1"?> <!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <document> <properties> <title>Configuration <author email="email@example.com">Commons Documentation Team </properties> <body> <!-- <section name="Introduction"> <p>TODO: add section about tomcat configuration and avoiding the resource leak when reloading tomcat webapps. </section> --> <!-- <section name="Dynamic Properties"> maxActive maxIdle minIdle maxWait testOnBorrow testOnReturn timeBetweenEvictionRunsMillis numTestsPerEvictionRun minEvictableIdleTimeMillis testWhileIdle </section> --> <section name="Parameters"> <table> <hr>
|Parameter||Default||Description<tr> <td>defaultAutoCommit <td>true <td>The default auto-commit state of connections created by this pool. </tr> <tr> <td>defaultReadOnly <td>driver default <td>The default read-only state of connections created by this pool. If not set then the setReadOnly method will not be called. (Some drivers don't support read only mode, ex: Informix) </td> </tr> <tr> <td>defaultTransactionIsolation <td>driver default <td>The default TransactionIsolation state of connections created by this pool. One of the following: (see <a href="http://java.sun.com/j2se/1.4.2/docs/api/java/sql/Connection.html#field_summary">javadoc) <ul> <li>NONE <li>READ_COMMITTED <li>READ_UNCOMMITTED <li>REPEATABLE_READ <li>SERIALIZABLE </ul> </td> </tr> <tr> <td>defaultCatalog <td> <td>The default catalog of connections created by this pool. </tr> </table> <table> <hr>||Parameter||Default||Description<tr> <td>initialSize <td>0 <td> The initial number of connections that are created when the pool is started. <br/>Since: 1.2 </td> </tr> <tr> <td>maxActive <td>8 <td> The maximum number of active connections that can be allocated from this pool at the same time, or negative for no limit. </td> </tr> <tr> <td>maxIdle <td>8 <td> The maximum number of connections that can remain idle in the pool, without extra ones being released, or negative for no limit. </td> </tr> <tr> <td>minIdle <td>0 <td> The minimum number of connections that can remain idle in the pool, without extra ones being created, or zero to create none. </td> </tr> <tr> <td>maxWait <td>indefinitely <td> The maximum number of milliseconds that the pool will wait (when there are no available connections) for a connection to be returned before throwing an exception, or -1 to wait indefinitely. </td> </tr> </table> <p> <img src="images/icon_warning_sml.gif"/> <strong>NOTE: If maxIdle is set too low on heavily loaded systems it is possible you will see connections being closed and almost immediately new connections being opened. This is a result of the active threads momentarily closing connections faster than they are opening them, causing the number of idle connections to rise above maxIdle. The best value for maxIdle for heavily loaded system will vary but the default is a good starting point. </p> <table> <hr>||Parameter||Default||Description<tr> <td>validationQuery <td> <td> The SQL query that will be used to validate connections from this pool before returning them to the caller. If specified, this query <strong>MUST be an SQL SELECT statement that returns at least one row. </td> </tr> <tr> <td>testOnBorrow <td>true <td> The indication of whether objects will be validated before being borrowed from the pool. If the object fails to validate, it will be dropped from the pool, and we will attempt to borrow another.<br/> <strong>NOTE - for a||Parameter||Default||Description|
|Parameter||Default||Description<tr> <td>removeAbandoned <td>false <td> Flag to remove abandoned connections if they exceed the removeAbandonedTimout.<br/> If set to true a connection is considered abandoned and eligible for removal if it has been idle longer than the removeAbandonedTimeout. Setting this to true can recover db connections from poorly written applications which fail to close a connection. </td> </tr> <tr> <td>removeAbandonedTimeout <td>300 <td>Timeout in seconds before an abandoned connection can be removed. </tr> <tr> <td>logAbandoned <td>false <td> Flag to log stack traces for application code which abandoned a Statement or Connection.<br/> Logging of abandoned Statements and Connections adds overhead for every Connection open or new Statement because a stack trace has to be generated. </td> </tr> </table> <p> <img src="images/icon_info_sml.gif"/> If you have enabled "removeAbandoned" then it is possible that a connection is reclaimed by the pool because it is considered to be abandoned. This mechanism is triggered when (getNumIdle() < 2) and (getNumActive() > getMaxActive() - 3) </p> <p> <img src="images/icon_info_sml.gif"/> For example maxActive=20 and 18 active connections and 1 idle connection would trigger the "removeAbandoned". But only the active connections that aren't used for more then "removeAbandonedTimeout" seconds are removed, default (300 sec). Traversing a resultset doesn't count as being used. </p> </section> </body> </document>|
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