sqlfacade.java

以前写的通用数据库接口

package util.database;

import java.sql.*;
import java.io.*;
/**
 * SqlFacade
 * 处理数据库的连接和访问
 *
 * @author Michael Zeng
 * @version 1.0 September 18, 2002
 */
public class SqlFacade
{

	private Connection conn = null;
	private Statement stmt = null;
	private PreparedStatement prepstmt = null;


	/**
	 * 构造数据库的连接和访问类,使用Statement
	 *
	 * @param conn 给定的连接
     *
     * @throws SQLException
	 */
	public SqlFacade(Connection conn) throws SQLException
	{
		this.conn = conn;
		stmt = this.conn.createStatement();
	}

    /**
     * 构造数据库的连接和访问类,使用Statement。使用滚动的结果集，默认游标只读。
     *
     * @param conn 给定的连接
     * @param isScrollSensitive 滚动敏感性标识
     *
     * @throws SQLException
     */
    public SqlFacade(Connection conn, boolean isScrollSensitive) throws SQLException
    {
        this.conn = conn;
        if(isScrollSensitive == false)
            this.stmt = this.conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
        else
            this.stmt = this.conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
	}

	/**
	 * 构造数据库的连接和访问类,使用PreparedStatement
	 *
	 * @param conn 给定的连接
	 * @param sql 包含占位符的SQL语句
     *
     * @throws SQLException
	 */
	public SqlFacade(Connection conn, String sql) throws SQLException
	{
		this.conn = conn;
 		this.prepareStatement(sql);
	}

    /**
     * 构造数据库的连接和访问类,使用PreparedStatement，使用滚动的结果集，默认游标只读。
     *
     * @param conn 给定的连接
     * @param sql 包含占位符的SQL语句
     * @param isScrollSensitive 滚动敏感性标识
     *
     * @throws SQLException
     */
    public SqlFacade(Connection conn, String sql,  boolean isScrollSensitive)
            throws SQLException
    {
        this.conn = conn;
        if(isScrollSensitive == false)
            this.prepareStatement(sql, ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
        else
            this.prepareStatement(sql, ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_READ_ONLY);
	}

	/**
	 * 返回连接
	 *
	 * @return Connection 连接
	 */
	public Connection getConnection()
	{
		return conn;
	}

	/**
	 * PreparedStatement
	 *
	 * @param sql 预设SQL语句
     *
     * @throws SQLException
	 */
	public void prepareStatement(String sql) throws SQLException
	{
		prepstmt = conn.prepareStatement(sql);
	}

    /**
     * PreparedStatement指定结果集类型和同步类型
     *
     * @param sql 包含占位符的SQL语句
     * @param resultSetType 结果集类型
     * @param resultSetConcurrency 同步类型
     *
     * @throws SQLException
     */
    public void prepareStatement(String sql, int resultSetType, int resultSetConcurrency)
            throws SQLException
    {
        prepstmt = conn.prepareStatement(sql, resultSetType, resultSetConcurrency);
	}

	public void setString(int index,String value) throws SQLException
	{
		prepstmt.setString(index,value);
	}
	public void setInt(int index,int value) throws SQLException
	{
		prepstmt.setInt(index,value);
	}
	public void setBoolean(int index,boolean value) throws SQLException
	{
		prepstmt.setBoolean(index,value);
	}
	public void setDate(int index,Date value) throws SQLException
	{
		prepstmt.setDate(index,value);
	}
	public void setLong(int index,long value) throws SQLException
	{
		prepstmt.setLong(index,value);
	}
	public void setFloat(int index,float value) throws SQLException
	{
		prepstmt.setFloat(index,value);
	}
	public void setBinaryStream(int index,InputStream in,int length) throws SQLException
	{
		prepstmt.setBinaryStream(index,in,length);
	}

	/**
     * 清除所有设定的参数
     *
     * @throws SQLException
     */
    public void clearParameters() throws SQLException
    {
        prepstmt.clearParameters();
    }

	/**
	 * 返回预设状态的准备语句
	 *
	 * @return PreparedStatement语句
	 */
	public PreparedStatement getPreparedStatement()
	{
		return prepstmt;
	}

	/**
	 * 返回状态的语句
	 * @return Statement 状态
	 */
	public Statement getStatement()
	{
		return stmt;
	}

	/**
	 * 执行SQL语句返回字段集，使用Statement语句
	 *
	 * @param sql SQL语句
	 * @return ResultSet 字段集
     *
     * @throws SQLException
	 */
	public ResultSet executeQuery(String sql) throws SQLException
	{
		if (stmt == null)   stmt = this.conn.createStatement();
        return stmt.executeQuery(sql);

	}

	/**
	 * 执行设定好的PreparedStatement语句返回字段集，使用PreparedStatement语句
     *
	 * @return ResultSet 字段集
     *
     * @throws SQLException
     */
	public ResultSet executeQuery() throws SQLException
	{
		if (prepstmt != null)
			return prepstmt.executeQuery();
		else
			return null;
	}

	/**
	 * 执行SQL Update语句,使用Statement语句
	 *
	 * @param sql SQL语句
     *
     * @throws SQLException
	 */
	public void executeUpdate(String sql) throws SQLException
	{
        if (stmt == null)   stmt = this.conn.createStatement();
        stmt.executeUpdate(sql);
	}

	/**
	 * 执行SQL Update语句,使用PreparedStatement语句
	 *
     * @throws SQLException
	 */
	public void executeUpdate() throws SQLException
	{
		if (prepstmt != null)
			prepstmt.executeUpdate();
	}

	/**
	 * 关闭Statement和PreparedStatement
     *
     * @throws SQLException
	 */
	public void close() throws SQLException
	{
		if (stmt != null)
		{
			stmt.close();
			stmt = null;
		}
		if (prepstmt != null)
		{
			prepstmt.close();
			prepstmt = null;
		}
	}
}