Use of the JDBC Pool database connection pooling technology from Tomcat

Package com.action;
Import java.sql.Connection;
Import Java.sql.ResultSet;
Import java.sql.SQLException;
Import java.sql.Statement;
Import Org.apache.tomcat.jdbc.pool.DataSource;
Import org.apache.tomcat.jdbc.pool.PoolProperties; /* * Tomcat's own JDBC Pool connection pooling technology is said to be more efficient and will be used today to sort out the following: * Requires JAR package support: Tomcat-juli.jar * There are two ways to use this pool operation, one is to configure parameters in the project, and one to be like dbcp in con Text.xml File Configuration * First: Directly in the project file configuration, here omitted the contents of the configuration file, directly put the parameters into the Java code; (using such a pool operation in a standalone application) * */public class Tomcat_jdbc_pool {Publ  IC static void Main (string[] args) {poolproperties p = new Poolproperties (); Pool Management Object Instantiation P.seturl ("Jdbc:mysql://localhost:3306/jack"); Set the URL p.setdriverclassname ("Com.mysql.jdbc.Driver");//Set the driver p.setusername ("root");//Set the user name P.setpassword ("1");// Set Password p.setjmxenabled (true);//Set whether the Java Management extension is available to support JMX P.settestwhileidle (FALSE);//Set Idle If idle object collector is enabled P.settestonbor Row (true);//The Fetch connection checks the validity of the link when a pool instance is borrow, whether the pool operation is done in advance, and if true, the resulting pool instance is available; P.settestonreturn (false);//test the connection for a return P.S Etvalidationquery ("Select 1 ");//Verify the connection validity, this step can not save the test connection statement p.setvalidationinterval (30000);//authentication interval time//timebetweenevictionrunsmillis and Minevictableidletimemillis,//Their two mates, can continuously update connection objects in the connection pool,//when Timebetweenevictionrunsmillis is greater than 0 o'clock,
		Every timebetweenevictionrunsmillis time,//A thread is started to verify connection objects that have been idle for more than Minevictableidletimemillis in the connection pool. 
		P.settimebetweenevictionrunsmillis (30000);

		P.setminevictableidletimemillis (30000); P.setmaxactive (100);//connection pool maximum concurrent capacity p.setinitialsize (10);//When initializing connection pool, create connection number p.setmaxwait (10000);//timeout wait time in milliseconds p.setre Moveabandonedtimeout (60);//timeout (in seconds) p.setmaxidle (100);//maximum number of idle connections P.setminidle (10);//minimum number of idle connections p.setlogabandoned ( true); Whether to print the connection Timeout error p.setremoveabandoned (true) when the time-out connection is automatically reclaimed,//whether the auto-recycle timeout connection//setup JDBC Interceptor p.setjdbcinterceptors ("org.apache.t Omcat.jdbc.pool.interceptor.ConnectionState; "
		
		
		+ "Org.apache.tomcat.jdbc.pool.interceptor.StatementFinalizer"); DataSource DataSource = new DataSource ();//tomcat data source datasource.setpoolproperties (p); Pool and data source bindingFixed Connection con = null;
			try {con = datasource.getconnection ();
			Statement st = Con.createstatement ();
			ResultSet rs = st.executequery ("SELECT * from student"); while (Rs.next ()) {System.out.println (".
			Host: "+ rs.getstring (2) +" Password: "+ rs.getstring (3));
			} rs.close ();
			
		St.close ();
		} catch (SQLException e) {e.printstacktrace ();
				} finally {if (con! = null) try {con.close (); } catch (Exception ignore) {}}}}

If you use this technique as a global technique, you will need to write the configuration information in the context.xml file of the Tomcat Conf folder (parameters refer to the comments above):

	<resource 
	name= "Jdbc/testdb" 
	auth= "Container" 
	type= "Javax.sql.DataSource" 
	factory= " Org.apache.tomcat.jdbc.pool.DataSourceFactory " 
	testwhileidle=" true " 
	testonborrow=" true " 
	Testonreturn= "false" 
	validationquery= "Select 1" 
	validationinterval= "30000" 
	Timebetweenevictionrunsmillis= "30000" 
	maxactive= " 
	minidle=" 
	maxwait= 
	"10000" Initialsize= "Ten" 
	removeabandonedtimeout= " 
	removeabandoned=" true " 
	logabandoned=" true " 
	Minevictableidletimemillis= "30000" 
	jmxenabled= "true" 
	jdbcinterceptors= " Org.apache.tomcat.jdbc.pool.interceptor.connectionstate;o Rg.apache.tomcat.jdbc.pool.interceptor.StatementFinalizer "  
	username=" root " 
	password=" password " 
	Driverclassname= "Com.mysql.jdbc.Driver" 
	url= "Jdbc:mysql://localhost:3306/mysql"/>

Note: Get the connection asynchronously

1. Fairqueue must be set to True

2. The data source must be converted to Org.apache.tomcat.jdbc.pool.DataSource

		   The connection pool gets
	    Connection conn = null;
	    DataSource ds = null;
	    ResultSet rs  =null;
	    Statement stmt = null;
	    Context initctx = new InitialContext ();
	    ds = (DataSource) initctx.lookup ("Java:comp/env/jdbc/ens");
	   if (ds!=null) {
	        out.println ("already obtained datasource!"); 
	        Out.println ("<br>");
	        conn = Ds.getconnection ();
	       try{
	        stmt = Conn.createstatement ();
	        String sql = "SELECT * from Ens_area";
	        rs = stmt.executequery (sql);
	        Out.println ("The following is the data read from the database:<br>");
	            while (Rs.next ()) {
	                out.println ("<br>");
	                Out.println (rs.getstring ("Area_name"));
	            }
	       } catch (Exception ex) {
	         ex.printstacktrace ();
	       } finally{
	          conn.close ();
	          Rs.close ();
	          Stmt.close ();
	       }
	   }