有时要为每一篇文章统计其点击次数,如果每一次浏览都要更新一次库的话,那性能在访问量很大的情况下,服务器的压力就会很大了,比较好一点的方法就是先将要更新的数据缓存起来,然后每隔一段时间再利用数据库的批量处理,批量更新库。源码如下: *^?tr?e%I<
At7!Pas#@g
CountBean.java .D*Qu}
EC+t-:a]
/* ^~4]"J};M
* CountData.java @6
he!wW
* 4_#$k{
* Created on 2007年1月1日, 下午4:44 ?ANWI8'_j
* ]7HR
U6$
* To change this template, choose Tools | Options and locate the template under sW>%mnx
* the Source Creation and Management node. Right-click the template and choose ]ch=@IV
* Open. You can then make changes to the template in the Source Editor. "x,lL
*/ Yh<F-WOo2
[$y(>]~.
package com.tot.count; DV5hTw0
EP>u% ]#
/** oz!)x\m*H
* ~
'ZwD/!e
* @author &L6Ivpj-
*/ mxlh\'b
public class CountBean { Mh%{cLM
private String countType; v({O*OR
int countId; @-@Coy 4Tt
/** Creates a new instance of CountData */ t3L>@NWG
public CountBean() {} /~LE1^1&U
public void setCountType(String countTypes){ e!u]l
this.countType=countTypes;
*yZ6"
} yR$_ZXsd
public void setCountId(int countIds){ G(E1c"?
this.countId=countIds; `YOYC
} 5%-{r&
public String getCountType(){ }7.A~h
return countType; [$dVs16K
} <\229
public int getCountId(){ )%C.IZ_s2
return countId; 4$-R|@,|_
} I;4quFBlMu
} gawY{Jr8I
!j!w$
CountCache.java P1F-Wy1
-}7$;QK&a
/* dL42)HP5
* CountCache.java {"o9pIh{~
* *@rA7zPFf
* Created on 2007年1月1日, 下午5:01 ]d*9@+Iu
* oW~W(h!
* To change this template, choose Tools | Options and locate the template under
Zkp~qx
* the Source Creation and Management node. Right-click the template and choose F^l1WX6
* Open. You can then make changes to the template in the Source Editor. gT}H B.
*/ &xGdKH
{B$CqsvJ
package com.tot.count; 80nE QT
y
import java.util.*; 7L~*%j
/** :WB uU
* '#Wx@
* @author V]zZb-m=
*/ 'sEnh<
public class CountCache { OZ`cE5"i
public static LinkedList list=new LinkedList(); E%w^q9C
/** Creates a new instance of CountCache */ k_pv6YrE
public CountCache() {} poz_=,c
public static void add(CountBean cb){ <) * U/r
if(cb!=null){ Xi="gxp$%
list.add(cb); yZlT#^$\
} Nd0tR3gi7
} (cj9xROx
} 6Zi{gx
juEPUsE
CountControl.java Q<sqlh!h
J2O,wb)U
/* e-dkvPr
* CountThread.java a_N7X
* Us`=^\
* Created on 2007年1月1日, 下午4:57
(?zg.y
* u^MKqI
* To change this template, choose Tools | Options and locate the template under p]aEC+q
* the Source Creation and Management node. Right-click the template and choose J3yK^@&&
* Open. You can then make changes to the template in the Source Editor. e#[Klh$]EW
*/ s^u Y
"7cty\
package com.tot.count; B.N#9u-vW
import tot.db.DBUtils; ` o)KG,
import java.sql.*; 7xnj\9$m
/** ZTR9e\F
* N
R
c4*zQJ
* @author < $zJi V
*/ 'lIs`Zc5N
public class CountControl{ ysnW3q!@
private static long lastExecuteTime=0;//上次更新时间 5>}$]d/o
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 MCN>3/81
/** Creates a new instance of CountThread */ ']k<'`b|
public CountControl() {} FJvY`zqB
public synchronized void executeUpdate(){ HXq']+iC
Connection conn=null; JM7mQ'`Ud
PreparedStatement ps=null; ?L<B]!9HZt
try{ ~& -h5=3
conn = DBUtils.getConnection(); 5RPG3ppS
conn.setAutoCommit(false); sVyV|!K
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); r;Sk[Y5#
for(int i=0;i<CountCache.list.size();i++){ u=:f%l
CountBean cb=(CountBean)CountCache.list.getFirst(); /+*"*Br/
CountCache.list.removeFirst(); bZ*=fdh
ps.setInt(1, cb.getCountId()); u99a"+
ps.executeUpdate();⑴ _xKn2 ?d8g
//ps.addBatch();⑵
7)2K6<q
} F`g(vD>
//int [] counts = ps.executeBatch();⑶ H07\z1?.K
conn.commit(); #eW
T-m
}catch(Exception e){ ~0MpB~ {xd
e.printStackTrace(); j_JY[sex
} finally{ Tpl]\L1v-
try{ ggDT5hb
if(ps!=null) { bRvGetX
ps.clearParameters(); @&\Y:aRO%i
ps.close(); $tZ
{>!N
ps=null; 5`^@k<
} f|{iW E2d
}catch(SQLException e){} 868X/lL
DBUtils.closeConnection(conn); s%:fZ7y
} fo ~uI(rk
} wm~7`&
public long getLast(){ 3U<m\A1
return lastExecuteTime; ceUe*}\cr
} B=0^Rysg
public void run(){ 9q"kM
long now = System.currentTimeMillis(); 4l 67B]o
if ((now - lastExecuteTime) > executeSep) { x9YQd69
//System.out.print("lastExecuteTime:"+lastExecuteTime); <YvXyIs
//System.out.print(" now:"+now+"\n"); E+]}KX:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zud_BOq{f
lastExecuteTime=now; Im;%.J
executeUpdate(); X%yG{\6:
} :[CV_ME.;
else{ UWT%0t_T
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); o]1BWwtY&
} S= 4o@3%$
} 9xR5Jm>k
} wQSan&81Q
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ABCm2$<
Yg&(kmm
类写好了,下面是在JSP中如下调用。 ?X@!jB,Pv
7P1Pk?pxy
<% {s8c@-'
CountBean cb=new CountBean(); >pF* unC;
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); zj7ta[<tr
CountCache.add(cb); ~nA k-toJ
out.print(CountCache.list.size()+"<br>"); x3y+=aj
CountControl c=new CountControl(); Tz1^"tx9
c.run(); i(4<MB1a
out.print(CountCache.list.size()+"<br>"); }Ulxt:}
%>