dbconnect.java

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/*
 * 创建日期 2005-3-6
 *
 * TODO 要更改此生成的文件的模板，请转至
 * 窗口 － 首选项 － Java － 代码样式 － 代码模板
 */
package store;

/**
 * @author wwx
 *
 * TODO 要更改此生成的类型注释的模板，请转至
 * 窗口 － 首选项 － Java － 代码样式 － 代码模板
 */
import java.sql.*;

public class DBConnect {
	private Connection conn;
	private Statement stmt;
	private PreparedStatement prepstmt;
	
	public DBConnect()
		throws Exception
	{
        String sDBDriver="org.postgresql.Driver";
        String sConnStr="jdbc:postgresql://localhost:5432/MyStore";
        conn = null;
        stmt = null;
        prepstmt = null;
        
        Class.forName(sDBDriver).newInstance();
        String user="postgres";
        String password="1234";
        conn=DriverManager.getConnection(sConnStr,user,password);
	}
	
	public void prepareStatement(String s)
		throws SQLException
	{
	      prepstmt = conn.prepareStatement(s);
	}
	
	public void prepareStatement(String s, int i, int j)
		throws SQLException
	{
		prepstmt = conn.prepareStatement(s, i, j);
	}
	
	public void setString(int i, String s)
		throws SQLException
	{
		prepstmt.setString(i, s);
	}
	
	public void setInt(int i, int j)
		throws SQLException
	{
		prepstmt.setInt(i, j);
	}
	
	public void setBoolean(int i, boolean flag)
		throws SQLException
	{
		prepstmt.setBoolean(i, flag);
	}
	
	public void setDate(int i, Date date)
		throws SQLException
	{
		prepstmt.setDate(i, date);
	}
	
	public void setLong(int i, long l)
		throws SQLException
	{
		prepstmt.setLong(i, l);
	}
	
	public void setFloat(int i, float f)
		throws SQLException
	{
		prepstmt.setFloat(i, f);
	}
	
	public void setBytes(int i, byte abyte0[])
		throws SQLException
	{
		prepstmt.setBytes(i, abyte0);
	}
	
	public void clearParameters()
		throws SQLException
	{
		prepstmt.clearParameters();
		prepstmt = null;
	}
	
	public PreparedStatement getPreparedStatement()
	{
		return prepstmt;
	}
	
	public Statement getStatement()
	{
	      return stmt;
	}
	
	public ResultSet executeQuery(String s)
		throws SQLException
	{
		if(stmt != null)
			return stmt.executeQuery(s);
		else
			return null;
	}
	
	public ResultSet executeQuery()
		throws SQLException
	{
		if(prepstmt != null)
			return prepstmt.executeQuery();
		else
			return null;
	}
	
	public void executeUpdate(String s)
		throws SQLException
	{
		if(stmt != null)
			stmt.executeUpdate(s);
	}
	
	public void executeUpdate()
		throws SQLException
	{
		if(prepstmt != null)
			prepstmt.executeUpdate();
	}
	
	public void close()
		throws Exception
	{
		if(stmt != null)
		{
			stmt.close();
			stmt = null;
		}
		if(prepstmt != null)
		{
			prepstmt.close();
			prepstmt = null;
		}
		if(conn != null)
		{
			conn.close();
			conn = null;
		}
	}
}