ConnectionPooljar數(shù)據(jù)連接池文件包的制作流程

1、關(guān)于ConnectionPool.jar數(shù)據(jù)連接池文件包的制作流程目的：制作通用型數(shù)據(jù)連接池文件包，便于應(yīng)用于通用工程結(jié)構(gòu)：工程包內(nèi)classes目錄內(nèi)1.ConnectionPool ：連接池管理程序|_ConnectionPool.java|_ConnectionWrapper.java|_LogFile.java|_LogWriter.java|_MakeDateTime.java|_PoolManager.java2. com ：MySql JDBC驅(qū)動程序3. org ：MySql JDBC驅(qū)動程序4. net ：MSSqlserver JTDS 驅(qū)動程序5. javax ：Orac

2、le JDBC 驅(qū)動程序6. oracle ：Oracle JDBC 驅(qū)動程序制作流程：1. 新建一個工程命名為Pool，在工程內(nèi)建立一個war模塊命名為Poolwar；2. 在工程內(nèi)新建class文件，文件的包起名為ConnectionPool；3. 依次新建下列文件：ConnectionPool.java、ConnectionWrapper.java、LogFile.java、LogWriter.java、MakeDateTime.java、PoolManager.java4. 將Oracle for JDBC驅(qū)動classes12.jar文件用winrar解壓縮，得到j(luò)avax和orac

3、le兩個文件夾，將這兩個文件夾復(fù)制到Pool工程內(nèi)的classes目錄下；5. 將MS-Sqlserver for JDBC驅(qū)動jtds-1.2.jar文件用winrar解壓縮，得到net這個文件夾，將這個文件夾復(fù)制到Pool工程內(nèi)的classes目錄下；6. 將MySql for JDBC驅(qū)動mysql-connector-java-3.0.16-ga-bin.jar文件用winrar解壓縮，得到com和org兩個文件夾，將這兩個文件夾復(fù)制到Pool工程內(nèi)的classes目錄下；7. 如果需要添加其他驅(qū)動程序，可參照4-6進行；8. 選擇JBuilder工具條上Wizards-àA

4、rchive Builder ；9.Archive Builder Step 1 of 5 : Archive Type 選擇Basic（具體類型含義參考JBuilerX使用手冊）；10. Archive Builder Step 2 of 5 : 將Name 和 File 命名為需要的名字，這里同意將其命名為ConnectionPool，其他的選項均不做更改；11Archive Builder Step 3 of 5 : 指定結(jié)構(gòu)文件包含內(nèi)容，這里不做任何修改；12Archive Builder Step 4 of 5 : 將servlet 選擇為 Allways include all c

5、lasses and resources;13Archive Builder Step 4 of 5 : 保持默認(rèn)狀態(tài)不改變，按finish完成結(jié)構(gòu)文件的定義；14在工程窗口用鼠標(biāo)右鍵點 ConnectionPool 結(jié)構(gòu)，然后選擇make 生成結(jié)構(gòu)文件；使用方法：1. 將該jar文件添加到 ToolsàConfigure Librarise 中；2. 新加工程，在工程 Required Librarise 中添加該庫文件；3. 在工程中新建一個“連接池初始化類”負(fù)責(zé)建立數(shù)據(jù)連接；4. 在工程中新建一屬性文件-perties，負(fù)責(zé)描述數(shù)據(jù)庫驅(qū)動及用戶信息等，該屬性文件存放

6、的位置在PoolManager.java中定義；5. 在PoolManager.java中默認(rèn)為“./ perties”,該位置表示在/WEB-INF 目錄下；附錄：文件代碼*文件開始*perties /屬性文件*XBDBManager Propertiespoolname = sqlpool oraclepool 注：中間以空格分隔drivers = net.sourceforge.jtds.jdbc.Driver oracle.jdbc.driver.OracleDriver 注：中間以空格分隔logfile = d:logfile.txtsqlpool.url =

7、 jdbc:jtds:sqlserver:/:1433;DatabaseName=pdasqlpool.initconns=50sqlpool.maxconns=80sqlpool.user = pdasqlpool.password = pdapass1234oraclepool.url = jdbc:oracle:thin::1521:infodboraclepool.initconns=50oraclepool.maxconns=80oraclepool.user = tjoldoraclepool.password = tjold*文件結(jié)束*文件

8、開始*ConnectionPool.java*package ConnectionPool;import java.io.*;import java.sql.*;import java.util.*;public class ConnectionPool private String name; private String URL; private String user; private String password; private int maxConns; private int timeOut; private LogWriter logWriter; private int c

9、heckedOut; private Vector freeConnections = new Vector(); public ConnectionPool(String name, String URL, String user, String password, int maxConns, int initConns, int timeOut, PrintWriter pw, int logLevel) = name; this.URL = URL; this.user = user; this.password = password; this.maxConns =

10、 maxConns; this.timeOut = timeOut > 0 ? timeOut : 5; logWriter = new LogWriter(name, logLevel, pw); initPool(initConns); logWriter.log("New pool created", LogWriter.INFO); String lf = System.getProperty("line.separator"); logWriter.log( " url=" + URL + " user=&q

11、uot; + user + / " password=" + password + " initconns=" + initConns + " maxconns=" + maxConns + " logintimeout=" + this.timeOut, LogWriter.INFO); logWriter.log(getStats(), LogWriter.INFO); private void initPool(int initConns) for (int i = 0; i < initConns;

12、i+) try Connection pc = newConnection(); freeConnections.addElement(pc); catch (SQLException e) public Connection getConnection() throws SQLException logWriter.log("Request for connection received", LogWriter.DEBUG); try Connection conn = getConnection(timeOut * 1000); return new Connectio

13、nWrapper(conn, this); catch(SQLException e) logWriter.log(e, "Exception getting connection", logWriter.ERROR); throw e; synchronized void wrapperClosed(Connection conn) freeConnections.addElement(conn); checkedOut-; notifyAll(); logWriter.log("Returned wrapperClosed to pool", Log

14、Writer.INFO); logWriter.log(getStats(), LogWriter.INFO); private synchronized Connection getConnection(long timeout) throws SQLException / Get a pooled Connection from the cache or a new one. / Wait if all are checked out and the max limit has / been reached. long startTime = System.currentTimeMilli

15、s(); long remaining = timeout; Connection conn = null; while (conn = getPooledConnection() = null) try logWriter.log("Waiting for connection. Timeout=" + remaining, LogWriter.DEBUG); wait(remaining); catch (InterruptedException e) remaining = timeout - (System.currentTimeMillis() - startTi

16、me); if (remaining <= 0) / Timeout has expired logWriter.log("Time-out while waiting for connection", LogWriter.DEBUG); throw new SQLException("getConnection() timed-out"); / Check if the Connection is still OK if (!isConnectionOK(conn) / It was bad. Try again with the remaini

17、ng timeout logWriter.log("Removed selected bad connection from pool", LogWriter.ERROR); return getConnection(remaining); checkedOut+; logWriter.log("Delivered getConnection from pool", LogWriter.INFO); logWriter.log(getStats(), LogWriter.INFO); return conn; private boolean isConn

18、ectionOK(Connection conn) Statement testStmt = null; try if (!conn.isClosed() / Try to createStatement to see if it's really alive testStmt = conn.createStatement(); testStmt.close(); else return false; catch (SQLException e) if (testStmt != null) try testStmt.close(); catch (SQLException se) lo

19、gWriter.log(e, "Pooled Connection was not okay", LogWriter.ERROR); return false; return true; private Connection getPooledConnection() throws SQLException Connection conn = null; if (freeConnections.size() > 0) / Pick the first Connection in the Vector / to get round-robin usage conn =

20、(Connection) freeConnections.firstElement(); freeConnections.removeElementAt(0); else if (maxConns = 0 | checkedOut < maxConns) conn = newConnection(); return conn; private Connection newConnection() throws SQLException Connection conn = null; if (user = null) conn = DriverManager.getConnection(U

21、RL); else conn = DriverManager.getConnection(URL, user, password); logWriter.log("Opened a new connection", LogWriter.INFO); logWriter.log(getStats(), LogWriter.INFO); return conn; public synchronized void freeConnection(Connection conn) / Put the connection at the end of the Vector freeCo

22、nnections.addElement(conn); checkedOut-; notifyAll(); logWriter.log("Returned freeConnection to pool", LogWriter.INFO); logWriter.log(getStats(), LogWriter.INFO); public synchronized void release() Enumeration allConnections = freeConnections.elements(); while (allConnections.hasMoreElemen

23、ts() Connection con = (Connection) allConnections.nextElement(); try con.close(); logWriter.log("release Closed connection", LogWriter.INFO); catch (SQLException e) logWriter.log(e, "release Couldn't close connection", LogWriter.ERROR); freeConnections.removeAllElements(); pr

24、ivate String getStats() return "Total connections: " + (freeConnections.size() + checkedOut) + " Available: " + freeConnections.size() + " Checked-out: " + checkedOut; *文件結(jié)束*文件開始*ConnectionWrapper.java*package ConnectionPool;import java.sql.*;import java.util.*;/* * Thi

25、s class is a wrapper around a Connection, overriding the * close method to just inform the pool that it's available for * reuse again, and the isClosed method to return the state * of the wrapper instead of the Connection. */class ConnectionWrapper implements Connection / realConn should be priv

26、ate but we use package scope to / be able to test removal of bad connections Connection realConn; private ConnectionPool pool; private boolean isClosed = false; public ConnectionWrapper(Connection realConn, ConnectionPool pool) this.realConn = realConn; this.pool = pool; /* * Inform the ConnectionPo

27、ol that the ConnectionWrapper * is closed. */ public void close() throws SQLException isClosed = true; pool.wrapperClosed(realConn); /* * Returns true if the ConnectionWrapper is closed, false * otherwise. */ public boolean isClosed() throws SQLException return isClosed; /* * Wrapped methods. */ pub

28、lic void clearWarnings() throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed"); realConn.clearWarnings(); public void commit() throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed"); realCmit(); public Statement c

29、reateStatement() throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed"); return realConn.createStatement(); public boolean getAutoCommit() throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed"); return realConn.get

30、AutoCommit(); public String getCatalog() throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed"); return realConn.getCatalog(); public DatabaseMetaData getMetaData() throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed&q

31、uot;); return realConn.getMetaData(); public int getTransactionIsolation() throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed"); return realConn.getTransactionIsolation(); public SQLWarning getWarnings() throws SQLException if (isClosed) throw new SQLExce

32、ption("Pooled connection is closed"); return realConn.getWarnings(); public boolean isReadOnly() throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed"); return realConn.isReadOnly(); public String nativeSQL(String sql) throws SQLException if (isCl

33、osed) throw new SQLException("Pooled connection is closed"); return realConn.nativeSQL(sql); public CallableStatement prepareCall(String sql) throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed"); return realConn.prepareCall(sql); public Prepared

34、Statement prepareStatement(String sql) throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed"); return realConn.prepareStatement(sql); public void rollback() throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed"); r

35、ealConn.rollback(); public void setAutoCommit(boolean autoCommit) throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed"); realConn.setAutoCommit(autoCommit); public void setCatalog(String catalog) throws SQLException if (isClosed) throw new SQLException(&qu

36、ot;Pooled connection is closed"); realConn.setCatalog(catalog); public void setReadOnly(boolean readOnly) throws SQLException if (isClosed) throw new SQLException("Pooled connection is closed"); realConn.setReadOnly(readOnly); public void setTransactionIsolation(int level) throws SQLE

37、xception if (isClosed) throw new SQLException("Pooled connection is closed"); realConn.setTransactionIsolation(level); public void setHoldability(int holdability) throws SQLException realConn.setHoldability(holdability); public int getHoldability() throws SQLException return realConn.getHo

38、ldability(); public Savepoint setSavepoint() throws SQLException return realConn.setSavepoint(); public Savepoint setSavepoint(String name) throws SQLException return realConn.setSavepoint(name); public void releaseSavepoint(Savepoint savepoint) throws SQLException realConn.releaseSavepoint(savepoin

39、t); public void rollback(Savepoint savepoint) throws SQLException realConn.rollback(savepoint); public Statement createStatement(int resultSetType, int resultSetConcurrency, int resultSetHoldability) throws SQLException return realConn.createStatement(resultSetType,resultSetConcurrency,resultSetHoldability); public PreparedStatement prepareSta