connectionwrapper.java

cmpp的开发的短信端口实例

package com.zhanghao.common.database;

import java.sql.*;
import java.util.Vector;
import java.util.Map;

import com.zhanghao.common.util.*;

/**
 * <p>数据库连接包装类。 </p>
 * <p>Description: </p>
 * <p>Copyright: Copyright (c) 2004</p>
 * <p>Company: </p>
 * @author not attributable
 * @version 1.0
 */

class ConnectionWrapper implements Connection {
  private Vector freeConns;  //用来存放数据库连接的集合，参见ConnectionPool类的freeConns属性
  private Connection conn;    //被包装的数据库连接
  private long createdTime;   //数据库连接建立的时间。用长整型数字代表时间

  /**
   * 构造器。只供同一个包内的类使用。具体说来，只供ConnectionPool类使用
   * @param conn  数据库连接
   * @param freeConns  用来存放数据库连接的集合，参见ConnectionPool类的freeConns属性
   * @throws SQLException
   */
  ConnectionWrapper(Connection conn,Vector freeConns) throws SQLException {
    if(conn==null || freeConns==null){
      throw new SQLException("ConnectionWrapper,建立数据库连接失败");
    }

    this.conn = conn;
    this.freeConns = freeConns;
    createdTime = System.currentTimeMillis();
  }

  /**
   * 私有造器。用一个新的包装器来包装数据库连接，连接建立时间按照原来的时间计算。
   * 本构造器只用在这个类的close()方法里
   * @param wrapper  数据库连接包装类
   * @param freeConns  用来存放数据库连接的集合，参见ConnectionPool类的freeConns属性
   * @throws SQLException
   */
  private ConnectionWrapper(ConnectionWrapper wrapper) {
    this.conn = wrapper.conn;
    this.freeConns = wrapper.freeConns;
    this.createdTime = wrapper.createdTime;
  }

  /**
   * 取得被包装的物理连接。
   * 这个方法只供ConnectionPool类调用
   * @return  物理连接
   */
  Connection getPhysicalConnection(){
    return conn;
  }

  /**
   * 取得本连接的建立时间。这个方法只供ConnectionPool类调用
   * @return 建立时间
   */
  long getCreatedTime(){
      return createdTime;
  }

  /**
   * 释放数据库连接
   * @throws SQLException
   */
  public void close()  throws SQLException{
    //本方法并不真正释放物理的数据库连接，只是把它返回数据库连接池

    ConnectionWrapper newWrapper = new ConnectionWrapper(this);
    this.conn = null;  //把指针置为空
    //把物理的数据库连接用新的包装器包装后，放回到连接池队列的最后：
    freeConns.addElement(newWrapper);
  }

  public boolean isClosed() throws SQLException {
    if(conn==null)
      return true;

    return conn.isClosed();
  }

  public Statement createStatement() throws SQLException {
    //checkClosed();
    return conn.createStatement();
  }

  public PreparedStatement prepareStatement(String sql) throws SQLException{
    return conn.prepareStatement(sql);
  }

  public CallableStatement prepareCall(String sql) throws SQLException {
    return conn.prepareCall(sql);
  }

  public String nativeSQL(String sql) throws SQLException{
     return conn.nativeSQL(sql);
  }

  public void setAutoCommit(boolean autoCommit) throws SQLException{
      conn.setAutoCommit(autoCommit);
  }

  public boolean getAutoCommit() throws SQLException{
      return conn.getAutoCommit();
  }

  public void commit() throws SQLException {
    conn.commit();
  }

  public void rollback() throws SQLException{
    conn.rollback();
  }

  public DatabaseMetaData getMetaData() throws SQLException{
    return conn.getMetaData();
  }

  public void setReadOnly(boolean readOnly)  throws SQLException{
    conn.setReadOnly(readOnly);
  }

  public boolean isReadOnly() throws SQLException{
      return conn.isReadOnly();
  }

  public void setCatalog(String catalog) throws SQLException{
    conn.setCatalog(catalog);
  }

  public String getCatalog()  throws SQLException{
    return conn.getCatalog();
  }

  public void setTransactionIsolation(int level) throws SQLException{
    conn.setTransactionIsolation(level);
  }

  public int getTransactionIsolation() throws SQLException {
    return conn.getTransactionIsolation();
  }

  public SQLWarning getWarnings() throws SQLException{
    return conn.getWarnings();
  }

  public void clearWarnings() throws SQLException{
    conn.clearWarnings();
  }

  public Statement createStatement(int resultSetType, int resultSetConcurrency)
                            throws SQLException{
    return conn.createStatement(resultSetType,resultSetConcurrency);
  }

  public PreparedStatement prepareStatement(String sql,
                                            int resultSetType,
                                            int resultSetConcurrency)
                                     throws SQLException{
    return conn.prepareStatement(sql,resultSetType,resultSetConcurrency);
  }

  public CallableStatement prepareCall(String sql,
                                       int resultSetType,
                                       int resultSetConcurrency)
                                throws SQLException{
    return conn.prepareCall(sql,resultSetType,resultSetConcurrency);
  }

  public Map getTypeMap()                throws SQLException{
    return conn.getTypeMap();
  }

  public void setTypeMap(Map map)                  throws SQLException{
    conn.setTypeMap(map);
  }

  public void setHoldability(int holdability)  throws SQLException{
    conn.setHoldability(holdability);
  }

  public int getHoldability() throws SQLException{
    return conn.getHoldability();
  }

  public Savepoint setSavepoint()  throws SQLException{
    return conn.setSavepoint();
  }

  public Savepoint setSavepoint(String name)   throws SQLException {
    return conn.setSavepoint(name);
  }

  public void rollback(Savepoint savepoint)   throws SQLException{
    conn.rollback(savepoint);
  }

  public void releaseSavepoint(Savepoint savepoint) throws SQLException{
    conn.releaseSavepoint(savepoint);
  }

  public Statement createStatement(int resultSetType,
                                   int resultSetConcurrency,
                                   int resultSetHoldability)
                            throws SQLException{
     return conn.createStatement(resultSetType,resultSetConcurrency,resultSetHoldability);
  }

  public PreparedStatement prepareStatement(String sql,
                                            int resultSetType,
                                            int resultSetConcurrency,
                                            int resultSetHoldability)
                                     throws SQLException{
    return conn.prepareStatement(sql,resultSetType,
                                 resultSetConcurrency,resultSetHoldability);
  }

  public CallableStatement prepareCall(String sql,
                                       int resultSetType,
                                       int resultSetConcurrency,
                                       int resultSetHoldability)
                                throws SQLException{
     return conn.prepareCall(sql,resultSetType,
                resultSetConcurrency,resultSetHoldability);
  }

  public PreparedStatement prepareStatement(String sql,
                  int autoGeneratedKeys) throws SQLException{
    return conn.prepareStatement(sql,autoGeneratedKeys);
  }

  public PreparedStatement prepareStatement(String sql,
            int[] columnIndexes)  throws SQLException{
    return conn.prepareStatement(sql,columnIndexes);
  }

  public PreparedStatement prepareStatement(String sql,
              String[] columnNames)  throws SQLException {
    return conn.prepareStatement(sql,columnNames);
  }



}