JDBC连接池（The JDBC connection pool）.docVIP

JDBC连接池（The JDBC connection pool） Modify the copied version, which is a bit BUG, two classes, one usage ConnectionPool class: SQL; package com. Vl. Import the Java. SQL. Connection; Import the Java. SQL. DatabaseMetaData; Import the Java. SQL. Driver; Import the Java. SQL. DriverManager; Import the Java. SQL. The ResultSet; Import the Java. SQL. SQLException; Import the Java. Util. Enumeration; Import the Java. Util. Vector; Public class ConnectionPool { Private String jdbcDriver = ; / / database driven Private String dbUrl = ; / / data URL Private String dbUsername = ; / / database user name Private String dbPassword = ; / / database user password Private String testTable = ; / / the test table name that is available for test connection is not tested by default Private int initialConnections = 1; / / the initial size of the connection pool Private int incrementalConnections = 5; / / the size of the connection pool automatically increases Private int maxConnections = 20; / / the maximum size of the connection pool Private Vector PooledConnection connections = null; / / the vector that holds the database connection in the connection pool, / / the initial time is null / / the object stored in it is the PooledConnection type / * * * * constructor * * * * @ param jdbcDriver * String JDBC driver String * * @ param dbUrl * String database URL * * @ param dbUsername * String to connect to the database user name * * @ param dbPassword * String the password for the database user * * * / Public ConnectionPool (String jdbcDriver, String dbUrl, String dbUsername, String dbPassword) { Enclosing jdbcDriver = jdbcDriver; Enclosing dbUrl = dbUrl; Enclosing dbUsername = dbUsername; Enclosing dbPassword = dbPassword; Try { CreatePool (); } catch (Exception e) { E.p rintStackTrace (); } } / * * * * return the initial size of the connection pool * * * * the number of connections available in the initial connection pool of * @return * / Public int getInitialConnections () { Return thi