JSP经典代码

package cn.com.zzb.eshopping.db; import java.sql.*; import javax.naming.InitialContext; import javax.sql.DataSource; public class DBConnect { private Connection conn; private Statement stmt; private PreparedStatement pstmt; private ResultSet rst; private String str; /** * 获得数据库的一个Connection连接 */ private void init() { try { //Class.forName("com.mysql.jdbc.Driver").newInstance(); //String url = "jdbc:mysql://localhost/mydb1"; //conn = DriverManager.getConnection(url,"root","12345"); InitialContext ctx = new InitialContext(); DataSource ds = (DataSource)ctx.lookup("java:comp/env/jdbc/mysql"); conn = ds.getConnection(); } catch(Exception e) { e.printStackTrace(); } } //******************************************* /** * 不带参数的构造函数 */ public DBConnect() { try { init(); //获得一个数据库连接 stmt = conn.createStatement(); } catch(Exception e) { e.printStackTrace(); } } /** * 带s参数的构造函数 */ public DBConnect(String s) { try { init(); pstmt = conn.prepareStatement(s); } catch(Exception e) { e.printStackTrace(); } } /** * 批处理sql语句 */ public DBConnect(StringBuffer sb) { try { init(); stmt = conn.createStatement(); stmt.addBatch(sb.toString()); } catch(Exception e) { e.printStackTrace(); } } // ******************************************* /** * 执行数据库查询语句，s为sql语句，把查询结果赋给ResultSet */ public void excuteQuery(String s) { try { if(stmt != null) { rst = stmt.executeQuery(s); } } catch(Exception e) { e.printStackTrace(); } } public void excuteQuery() { try { if(pstmt != null) { rst = pstmt.executeQuery(); } } catch(Exception e) { e.printStackTrace(); } } /** * 对数据库进行update操作 */ public int excuteUpdate(String s) { int status = 0; try { if(stmt != null) status = stmt.executeUpdate(s); } catch(Exception e) { e.printStackTrace(); } return status; } public int excuteUpdate() { int status = 0; try { if(pstmt != null) { status = pstmt.executeUpdate(); } } catch(Exception e) { e.printStackTrace(); } return status; } public int[] excuteBatch() { int[] status = null; try { if(stmt != null) { status = stmt.executeBatch(); } } catch(Exception e) { e.printStackTrace(); } return status; } //************************************************* /** * */ public void setString(int i,String s) { try { pstmt.setString(i,s); } catch(Exception e) { e.printStackTrace(); } } public void setBoolean(int i, boolean flag) { try{ pstmt.setBoolean(i, flag);} catch(Exception e) { e.printStackTrace(); } } public void setByte(int i, byte byte0) { try{pstmt.setByte(i, byte0);} catch(Exception e){ e.printStackTrace(); } } public void setBytes(int i, byte abyte0[]) { try{pstmt.setBytes(i, abyte0);} catch(Exception e){ e.printStackTrace(); } } public void setDate(int i, Date date) { try{pstmt.setDate(i, date);} catch(Exception e) { e.printStackTrace(); } } public void setTime(int i, Time time) { try{pstmt.setTime(i,time);} catch(Exception e) { e.printStackTrace(); } } public void setShort(int i, short word0) { try{pstmt.setShort(i,word0);} catch(Exception e) {e.printStackTrace(); } } public void setInt(int i, int j) { try{pstmt.setInt(i,j);} catch(Exception e) { e.printStackTrace(); } } public void setLong(int i, long l) { try{pstmt.setLong(i, l);} catch(Exception e) { e.printStackTrace(); } } public void setFloat(int i, float f) { try{pstmt.setFloat(i, f);} catch(Exception e) { e.printStackTrace(); } } public void setDouble(int i, double d) { try{pstmt.setDouble(i, d);} catch(Exception e) {e.printStackTrace();} } //****************************************** /** * */ public boolean getBoolean(int i) throws Exception { return rst.getBoolean(i); } public boolean getBoolean(String s) throws Exception { return rst.getBoolean(s); } public byte getByte(int i) throws Exception { return rst.getByte(i); } public byte getByte(String s) throws Exception { return rst.getByte(s); } public byte[] getBytes(int i) throws Exception { return rst.getBytes(i); } public byte[] getBytes(String s) throws Exception { return rst.getBytes(s); } public Date getDate(int i) throws Exception { return rst.getDate(i); } public Date getDate(String s) throws Exception { return rst.getDate(s); } public Time getTime(int i) throws Exception { return rst.getTime(i); } public Time getTime(String s) throws Exception { return rst.getTime(s); } public double getDouble(int i) throws Exception { return rst.getDouble(i); } public double getDouble(String s) throws Exception { return rst.getDouble(s); } public float getFloat(int i) throws Exception { return rst.getFloat(i); } public float getFloat(String s) throws Exception { return rst.getFloat(s); } public int getInt(int i) throws Exception { return rst.getInt(i); } public int getInt(String s) throws Exception { return rst.getInt(s); } public long getLong(int i) throws Exception { return rst.getLong(i); } public long getLong(String s) throws Exception { return rst.getLong(s); } public short getShort(int i) throws Exception { return rst.getShort(i); } public short getShort(String s) throws Exception { return rst.getShort(s); } public String getString(int i) throws Exception { return rst.getString(i); } public String getString(String s) throws Exception { return rst.getString(s); } //*************************************** /** * */ public boolean next() { try { return rst.next(); } catch(Exception e) { e.printStackTrace(); return false; } } public void close() { try { if(conn !=null) conn.close(); if(pstmt !=null) pstmt.close(); if(stmt !=null) stmt.close(); if(rst != null) rst.close(); } catch(Exception e) { e.printStackTrace(); } } }