早餐2塊2

    /**
     * Override this to return the connection to a pool, or to clean up the
     * resource.
     *
     * The default behavior holds a single connection open until the appender
     * is closed (typically when garbage collected).
     */
    protected void closeConnection(Connection con) {
        mydb=null; 
        try {
           if (connection != null && !connection.isClosed())
               connection.close();
       } catch (SQLException e) {
           errorHandler.error("Error closing connection", e,
                              ErrorCode.GENERIC_FAILURE);
       }

    }

    /**
     * Override 此函數來利用連接池返回一個Connetion對象
     *    
     */
    protected Connection getConnection() throws SQLException { 
        try {
            mydb = GeneralDb.getInstance(sqlname);  
            connection = mydb.getConnection();     
       } catch (Exception e) {
            errorHandler.error("Error opening connection", e, ErrorCode.GENERIC_FAILURE);
        }
        return connection;
    }

    /**
     * Closes the appender, flushing the buffer first then closing the default
     * connection if it is open.
     */
    public void close() {
        flushBuffer();

        try {
            if (connection != null && !connection.isClosed())
                connection.close();
        } catch (SQLException e) {
            errorHandler.error("Error closing connection", e,
                               ErrorCode.GENERIC_FAILURE);
        }
        this.closed = true;
    }

    /**
     * loops through the buffer of LoggingEvents, gets a
     * sql string from getLogStatement() and sends it to execute().
     * Errors are sent to the errorHandler.
     *
     * If a statement fails the LoggingEvent stays in the buffer!
     */
    public void flushBuffer() {
        //Do the actual logging
        removes.ensureCapacity(buffer.size());
        for (Iterator i = buffer.iterator(); i.hasNext(); ) {
            try {
                LoggingEvent logEvent = (LoggingEvent) i.next();
                String sql = getLogStatement(logEvent);
                execute(sql);
                removes.add(logEvent);
            } catch (SQLException e) {
                errorHandler.error("Failed to excute sql", e,
                                   ErrorCode.FLUSH_FAILURE);
            }
        }

        // remove from the buffer any events that were reported
        buffer.removeAll(removes);

        // clear the buffer of reported events
        removes.clear();
    }

    /** closes the appender before disposal */
    public void finalize() {
        close();
    }

    /**
     * JDBCAppender requires a layout.
     * */
    public boolean requiresLayout() {
        return true;
    }

    /**
     *
     */
    public void setSql(String s) {
        sqlStatement = s;
        if (getLayout() == null) {
            this.setLayout(new PatternLayout(s));
        } else {
            ((PatternLayout) getLayout()).setConversionPattern(s);
        }
    }

    /**
     * Returns pre-formated statement eg: insert into LogTable (msg) values ("%m")
     */
    public String getSql() {
        return sqlStatement;
    }

    public void setSqlname(String sqlname){
        sqlname=sqlname;
    }
   
    public String getSqlname(){
        return sqlname;
    }   

    public void setBufferSize(int newBufferSize) {
        bufferSize = newBufferSize;
        buffer.ensureCapacity(bufferSize);
        removes.ensureCapacity(bufferSize);
    }

MyDB.java:
package common.sql;
import java.sql.*;
import com.codestudio.sql.*;  //引入開源項目Poolman數據庫連接池的包

public class MyDB {
    public static final String module = MyDB.class.getName();
    private String dbName = "";
    private PoolMan plmn = null;

    public MyDB(String dbName) {
        try {
            if (plmn == null) {
                plmn = (PoolMan) Class.forName("com.codestudio.sql.PoolMan").
                        newInstance();
            }
        } catch (Exception ec) {
           System.out.println(ec.toString()+module);
        }
        this.dbName = dbName;
    }

    private Connection getNewConnection() {
        Connection conn = null;
        try {
            conn = plmn.connect("jdbc:poolman://" + dbName);  
            conn.setAutoCommit(true);
        } catch (Exception ec) {
            System.out.println(ec.toString()+"First:Connect sqlsever failed"+module);
            try {
                Thread.sleep(1000);
                conn = plmn.connect("jdbc:poolman://" + dbName);
                conn.setAutoCommit(true);
            } catch (Exception ecs) {
               System.out.println(ecs.toString()+"Again:Connect sqlsever faile"+module);
            }
        }
        return conn;
    }