Java database connection pool and java Database Connection

Java database connection pool and java Database Connection

1. About

Java uses jdbc to directly connect to the database, and often gets the connection and runs out of release, which wastes system resources.

2. Code

Java code

Package com. cdv. mam. db; import java. SQL. connection; import java. SQL. databaseMetaData; import java. SQL. SQLException; import java. util. properties; import javax. SQL. dataSource; import org. apache. commons. dbcp. basicDataSourceFactory; import org. apache. commons. logging. log; import org. apache. commons. logging. logFactory; // import org. apache. tomcat. dbcp. dbcp. basicDataSourceFactory;/*** tomcat database connection pool management class <br> * used as container T deployment environment <br> * You need to prepare the database connection configuration file dbcp in the class path. properties **/public class DBManager {private static final Log log = LogFactory. getLog (DBManager. class); private static final String configFile = "dbcp. properties "; private static DataSource dataSource; static {Properties dbProperties = new Properties (); try {dbProperties. load (DBManager. class. getClassLoader (). getResourceAsStream (configFile); dataSource = Ba SicDataSourceFactory. createDataSource (dbProperties); Connection conn = getConn (); DatabaseMetaData mdm = conn. getMetaData (); log.info ("Connected to" + mdm. getDatabaseProductName () + "" + mdm. getDatabaseProductVersion (); if (conn! = Null) {conn. close () ;}} catch (Exception e) {log. error ("failed to initialize connection pool:" + e) ;}} private DBManager () {}/ *** get link, close ** @ see {@ link DBManager # closeConn (Connection)} * @ return */public static final Connection getConn () {Connection conn = null; try {conn = dataSource. getConnection ();} catch (SQLException e) {log. error ("failed to get database connection:" + e);} return conn;}/***** close connection ** @ param conn * need to be closed */Public static void closeConn (Connection conn) {try {if (conn! = Null &&! Conn. isClosed () {conn. setAutoCommit (true); conn. close () ;}} catch (SQLException e) {log. error ("failed to close database connection:" + e );}}}

Properties file (dbcp. properties)

# Database driver driverClassName = com. mysql. jdbc. driver # database connection Address url = jdbc: mysql: // 192.168.1.41: 3306/dmc # username = root # password = root # maximum number of database connections in the connection pool. If it is set to 0, there is no limit to maxActive = 30 # the maximum number of idle instances and the maximum idle time for database connection. When the idle time is exceeded, the database connection # is marked as unavailable and then released. If it is set to 0, maxIdle = 10 # The maximum connection wait time is set. If this time is exceeded, an exception occurs. If it is set to-1, maxWait = 1000 # If the removeAbandonedTimeout time is exceeded, whether to recycle connections (obsolete) is useless (false by default, adjusted to true) removeAbandoned = true # When the time limit is exceeded, the connections that are not used (discarded) are recycled (300 seconds by default, adjusted to 180) removeAbandonedTimeout = 180

Jar used