DBCP数据库连接池.doc

对于数据库数据不停的读取和更改，频繁的建立Connection是很不划算，建立连接池是很好的选择，在多个数据库数据之间来回倒换，需要为每个数据库建立一个池，本例的目的就是建立一个管理这些池的管理类，达到的目的是：在我们需要一个链接的时候，只要提供需要那个连接池（每个连接池对于一个名字，所有的连接池都装载入一个Map中）的名字，就可以得到链接进行操作，完毕需要关闭，关闭这个链接并不会真正的关闭，在池中他还是存在的。 首先定义个xml文件作为我们需要的连接池的配置文件：如下：config.xml Xml代码 1. 2. 3. 4. 5. one6. 7. name18. 9. pswd110. 11. jdbc:mysql:/IP/DataminInfo12. 13. 1014. 15. 16. 17. com.mysql.jdbc.Driver18. 19. 20. two21. name222. paswd223. jdbc:mysql:/IP/UIC24. 1025. 26. com.mysql.jdbc.Driver27. 28. one name1 pswd1 jdbc:mysql:/IP/DataminInfo 10 com.mysql.jdbc.Driver two name2 paswd2 jdbc:mysql:/IP/UIC 10 com.mysql.jdbc.Driver 作为对象操作，这个xml有相对应的Bean：如下： BaseConnBean.java Java代码 1. publicclassBaseConnBean 2. 3. privateStringname; 4. privateStringusername; 5. privateStringpassword; 6. privateStringjdbcurl; 7. privateintmax; 8. privatelongwait; 9. privateStringdriver; 10. publicStringgetDriver() 11. returndriver; 12. 13. publicvoidsetDriver(Stringdriver) 14. this.driver=driver; 15. 16. /其他setget方法 17. public class BaseConnBean private String name; private String username; private String password; private String jdbcurl; private int max; private long wait; private String driver; public String getDriver() return driver; public void setDriver(String driver) this.driver = driver; /其他set get方法还需要一个操作就是吧xml文件组装成Bean，并把这些bean加到list里面，代码如下 ConfigXml.java Java代码 1. importjava.io.FileInputStream; 2. importjava.io.FileNotFoundException; 3. importjava.io.IOException; 4. importjava.util.ArrayList; 5. importjava.util.Iterator; 6. importjava.util.List; 7. 8. importorg.jdom.Document; 9. importorg.jdom.Element; 10. importorg.jdom.JDOMException; 11. importorg.jdom.input.SAXBuilder; 12. 13. importcom.cgogo.mymodel.po.BaseConnBean; 14. 15. publicclassConfigXml 16. 17. publicstaticvoidmain(Stringargs) 18. read(config.xml); 19. 20. 21. publicstaticListread() 22. returnread(config.xml); 23. 24. 25. publicstaticListread(Stringpath) 26. Stringrpath=ConfigXml.class.getResource().getPath().substring(1) 27. +path; 28. FileInputStreamfi=null; 29. Listpools=newArrayList(); 30. try 31. fi=newFileInputStream(rpath); 32. SAXBuildersb=newSAXBuilder(); 33. Documentdoc=sb.build(fi); 34. Elementroot=doc.getRootElement(); 35. Listlist=root.getChildren(); 36. Elementpool=null; 37. IteratorallPool=list.iterator(); 38. while(allPool.hasNext() 39. pool=(Element)allPool.next(); 40. BaseConnBeanbcBean=newBaseConnBean(); 41. bcBean.setName(pool.getChildText(name); 42. 43. bcBean.setUsername(pool.getChildText(username); 44. bcBean.setPassword(pool.getChildText(password); 45. bcBean.setJdbcurl(pool.getChildText(jdbcurl); 46. try 47. bcBean.setMax(Integer.parseInt(pool.getChildText(max); 48. catch(NumberFormatExceptione) 49. bcBean.setMax(0); 50. 51. try 52. bcBean.setWait(Long.parseLong(pool.getChildText(wait); 53. catch(NumberFormatExceptione) 54. bcBean.setWait(-1L); 55. 56. bcBean.setDriver(pool.getChildText(driver); 57. pools.add(bcBean); 58. 59. catch(FileNotFoundExceptione) 60. System.out.println(filedoesnotfind); 61. e.printStackTrace(); 62. catch(JDOMExceptione) 63. System.out.println(jdomexception); 64. e.printStackTrace(); 65. catch(IOExceptione) 66. e.printStackTrace(); 67. 68. returnpools; 69. 70. import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.IOException;import java.util.ArrayList;import java.util.Iterator;import java.util.List;import org.jdom.Document;import org.jdom.Element;import org.jdom.JDOMException;import org.jdom.input.SAXBuilder;import com.cgogo.mymodel.po.BaseConnBean;public class ConfigXml public static void main(String args) read(config.xml); public static List read() return read(config.xml); public static List read(String path) String rpath = ConfigXml.class.getResource().getPath().substring(1) + path; FileInputStream fi = null; List pools=new ArrayList(); try fi = new FileInputStream(rpath); SAXBuilder sb = new SAXBuilder(); Document doc = sb.build(fi); Element root = doc.getRootElement(); List list=root.getChildren(); Element pool = null; Iterator allPool = list.iterator(); while(allPool.hasNext() pool=(Element) allPool.next(); BaseConnBean bcBean=new BaseConnBean(); bcBean.setName(pool.getChildText(name); bcBean.setUsername(pool.getChildText(username); bcBean.setPassword(pool.getChildText(password); bcBean.setJdbcurl(pool.getChildText(jdbcurl); try bcBean.setMax(Integer.parseInt(pool.getChildText(max); catch(NumberFormatException e) bcBean.setMax(0); try bcBean.setWait(Long.parseLong(pool.getChildText(wait); catch(NumberFormatException e) bcBean.setWait(-1L); bcBean.setDriver(pool.getChildText(driver); pools.add(bcBean); catch (FileNotFoundException e) System.out.println(file does not find); e.printStackTrace(); catch (JDOMException e) System.out.println(jdom exception); e.printStackTrace(); catch (IOException e) e.printStackTrace(); return pools; 最后，最关键的类就是管理类了，（需要增加dbcp的jar包，同时还需要commons-pools）代码如下 Java代码 1. 2. importjava.sql.Connection; 3. importjava.sql.DriverManager; 4. importjava.sql.SQLException; 5. importjava.util.HashMap; 6. importjava.util.List; 7. importjava.util.Map; 8. 9. mons.dbcp.ConnectionFactory; 10. mons.dbcp.DriverManagerConnectionFactory; 11. mons.dbcp.PoolableConnectionFactory; 12. mons.dbcp.PoolingDriver; 13. mons.pool.ObjectPool; 14. mons.pool.impl.GenericObjectPool; 15. 16. importcom.cgogo.mymodel.po.BaseConnBean; 17. importcom.cgogo.mymodel.util.ConfigXml; 18. 19. publicclassMyDbPool 20. publicstaticvoidmain(Stringargs) 21. 22. 23. 24. privatestaticStringdbJdbc=null; 25. 26. privatestaticStringdbUser=null; 27. 28. privatestaticStringdbPwd=null; 29. 30. privatestaticintmax; 31. 32. privatestaticlongwait; 33. 34. privatestaticStringdriver=null; 35. 36. privatestaticClassdriverClass=null; 37. 38. privatestaticObjectPoolconnectionPool=null; 39. 40. publicstaticMapmap=null; 41. 42. publicMyDbPool() 43. 44. 45. /*/* 46. *初始化数据源 47. */48. privatestaticsynchronizedvoidinitDataSource() 49. /驱动数据源 50. if(driverClass=null) 51. try 52. driverClass=Class.forName(driver); 53. catch(ClassNotFoundExceptione) 54. e.printStackTrace(); 55. 56. 57. 58. 59. /*/* 60. *连接池启动 61. * 62. *throwsException 63. */64. publicstaticvoidStartPool(Stringpoolname,StringdbJdbc,StringdbUser, 65. StringdbPwd,intmax,longwait) 66. /初始化数据源 67. initDataSource(); 68. /如果连接池为空 69. if(connectionPool!=null) 70. ShutdownPool(); 71. 72. try 73. connectionPool=newGenericObjectPool(null,max,(byte)1,wait); 74. ConnectionFactoryconnectionFactory=newDriverManagerConnectionFactory( 75. dbJdbc,dbUser,dbPwd); 76. PoolableConnectionFactorypoolableConnectionFactory=newPoolableConnectionFactory( 77. connectionFactory,connectionPool,null,null,false,true); 78. Class.forName(mons.dbcp.PoolingDriver); 79. PoolingDriverdriver=(PoolingDriver)DriverManager 80. .getDriver(jdbc:apache:commons:dbcp:); 81. driver.registerPool(poolname,connectionPool); 82. map.put(poolname,connectionPool); 83. System.out.println(Create+poolname 84. +forDatabaseConnectionSuccees.); 85. catch(Exceptione) 86. e.printStackTrace(); 87. 88. 89. 90. /*/* 91. *释放连接池 92. */93. publicstaticvoidShutdownPool() 94. try 95. PoolingDriverdriver=(PoolingDriver)DriverManager 96. .getDriver(jdbc:apache:commons:dbcp:); 97. driver.closePool(dbpool); 98. catch(SQLExceptione) 99. e.printStackTrace(); 100. 101. 102. 103. /*/* 104. *打印连接池状态 105. */106. publicstaticStringGetPoolStats(Stringpoolname) 107. 108. StringBufferstat=newStringBuffer(); 109. try 110. PoolingDriverdriver=(PoolingDriver)DriverManager 111. .getDriver(jdbc:apache:commons:dbcp:); 112. ObjectPoolconnectionPool=driver.getConnectionPool(poolname); 113. 114. stat.append(-ActiveConnection:); 115. stat.append(connectionPool.getNumActive(); 116. stat.append(,); 117. stat.append(FreeConnection:); 118. stat.append(connectionPool.getNumIdle(); 119. stat.append(.-); 120. catch(Exceptione) 121. e.printStackTrace(); 122. 123. returnstat.toString(); 124. 125. 126. /*/* 127. *取得连接池中的连接 128. * 129. *return 130. */131. publicsynchronizedstaticConnectiongetDbConnection(Stringpoolname) 132. Connectionconn=null; 133. if(map=null) 134. System.out.println(mapnull); 135. map=newHashMap(); 136. 137. if(map.get(poolname)=null) 138. init(poolname);/初始化基本数据 139. StartPool(poolname,dbJdbc,dbUser,dbPwd,max,wait); 140. 141. try 142. conn=DriverManager.getConnection(jdbc:apache:commons:dbcp:143. +poolname); 144. catch(SQLExceptione) 145. e.printStackTrace(); 146. 147. returnconn; 148. 149. 150. privatestaticvoidinit(Stringpoolname) 151. Listpools=ConfigXml.read(); 152. for(BaseConnBeanbaseConnBean:pools) 153. if(baseConnBean.getName().equals(poolname) 154. dbJdbc=baseConnBean.getJdbcurl(); 155. dbUser=baseConnBean.getUsername(); 156. dbPwd=baseConnBean.getPassword(); 157. max=baseConnBean.getMax(); 158. wait=baseConnBean.getWait(); 159. driver=baseConnBean.getDriver(); 160. 161. 162. 163. 164. 165. publicstaticvoidclose(Connectionc) 166. try 167. if(c!=null) 168. c.close(); 169. catch(SQLExceptione) 170. e.printStackTrace(); 171. 172. 173. 174. import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;import java.util.HashMap;import java.util.List;import java.util.Map;import mons.dbcp.ConnectionFactory;import mons.dbcp.DriverManagerConnectionFactory;import mons.dbcp.PoolableConnectionFactory;import mons.dbcp.PoolingDriver;import mons.pool.ObjectPool;import mons.pool.impl.GenericObjectPool;import com.cgogo.mymodel.po.BaseConnBean;import com.cgogo.mymodel.util.ConfigXml;public class MyDbPool public static void main(String args) private static String dbJdbc = null; private static String dbUser = null; private static String dbPwd = null; private static int max; private static long wait; private static String driver = null; private static Class driverClass = null; private static ObjectPool connectionPool = null; public static Map map = null; public MyDbPool() /* */* * 初始化数据源 */ private static synchronized void initDataSource() / 驱动数据源 if (driverClass = null) try driverClass = Class.forName(driver); catch (ClassNotFoundException e) e.printStackTrace(); /* */* * 连接池启动 * * throws Exception */ public static void StartPool(String poolname, String dbJdbc, String dbUser, String dbPwd, int max, long wait) / 初始化数据源 initDataSource(); / 如果连接池为空 if (connectionPool != null) ShutdownPool(); try connectionPool = new GenericObjectPool(null, max, (byte) 1, wait); ConnectionFactory connectionFactory = new DriverManagerConnectionFactory( dbJdbc, dbUser, dbPwd); PoolableConnectionFactory poolableConnectionFactory = new PoolableConnectionFactory( connectionFactory, connectionPool, null, null, false, true); Class.forName(mons.dbcp.PoolingDriver); PoolingDriver driver = (PoolingDriver) DriverManager .getDriver(jdbc:apache:commons:dbcp:); driver.registerPool(poolname, connectionPool); map.put(poolname, connectionPool); System.out.println(Create + poolname + for Database Connection Succees.); catch (Exception e) e.printStackTrace(); /* */* * 释放连接池 */ public static void ShutdownPool() try PoolingDriver driver = (PoolingDriver) DriverManager .getDriver(jdbc:apache:commons:dbcp:); driver.closePool(dbpool); catch (SQLException e)