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: FoQk
a=dN.OB}F7
CountBean.java i|mA/
e3b
Q<pM
tW
/* r
N7"%dx
* CountData.java GZo4uwG@a
* ,z3b2$
&A
* Created on 2007年1月1日, 下午4:44 (Q+3aEUE
* YBP{4Rl
* To change this template, choose Tools | Options and locate the template under e)kf;Hkf
* the Source Creation and Management node. Right-click the template and choose tDo0Q/`
* Open. You can then make changes to the template in the Source Editor. i_"I"5pBF
*/ 3[rB:cE/
<4g^c&
package com.tot.count; F`u~Jx8.*
0bE_iu>f'
/** PR+!CFi&
* l;uEw
* @author Gf?KpU
*/ jVz1`\Nje
public class CountBean { x-<dJ}`
private String countType; $c-3Q|C
int countId; \w3wh*
/** Creates a new instance of CountData */ J*k4&l
public CountBean() {} 5h1j.t!
public void setCountType(String countTypes){ ^4"_I
this.countType=countTypes; SxDE3A-:
} =%L^!//c
public void setCountId(int countIds){ NmQ]qv
this.countId=countIds; |j,Mof
} zP9!fA
public String getCountType(){ 1 .M?Hp9i
return countType; .<.qRq-
} }5k"aCno
public int getCountId(){ m{*l6`dF
return countId; C\{4<:<_&
} eZcm3=WV|
} Vr*t~M>
bbJa,}R
CountCache.java 9YJb~tuZ73
,"'agg:St
/* t]x HM
* CountCache.java 1jL?z6S
* GYYro&aq{
* Created on 2007年1月1日, 下午5:01 =N=,;<6%A
* (]1%s?ud*
* To change this template, choose Tools | Options and locate the template under [V2l&ZUni
* the Source Creation and Management node. Right-click the template and choose ^{s)`j'I*
* Open. You can then make changes to the template in the Source Editor. "rXGXQu
*/
d^w_rL
]HRZ9oP
package com.tot.count; a-3~HH
import java.util.*; & zG=
/** rdb%/@.-
* h %nZKhm
* @author Cdv TC`~,
*/ >eC^]#c
public class CountCache { #_E8>;)k
public static LinkedList list=new LinkedList(); \||PW58j
/** Creates a new instance of CountCache */ O7.Is88!
public CountCache() {} #U1soZ7
public static void add(CountBean cb){ {M$1?j"7
if(cb!=null){ &(0iSS
list.add(cb); ~DJ/sY2/
} b ,cvQD
} ZGf=/Ra
a
} {<GsM
EgY]U1{
CountControl.java "-hgeQX
4 QDW}5xB
/* %:??QD*
* CountThread.java j#*K[
* y|@^0]}%<
* Created on 2007年1月1日, 下午4:57 PC9:nee
*
oCduY2
* To change this template, choose Tools | Options and locate the template under nhIITfJJ
* the Source Creation and Management node. Right-click the template and choose YB 4R8}4
* Open. You can then make changes to the template in the Source Editor. v7ae^iU
*/ i{`>!)U
G q8/xxt
package com.tot.count; Z?GC+hG`
import tot.db.DBUtils; A.y$.(
import java.sql.*; vOqYt42
/** ;w1h)
* 9oaq%Sf
* @author "aP/214Ul
*/ E J 9A
4B
public class CountControl{ ]-R8W/fDn
private static long lastExecuteTime=0;//上次更新时间 :dK%=j*ZK
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4TLh'?Xu9
/** Creates a new instance of CountThread */ {!-w|&bF
public CountControl() {} d>(dSKx
public synchronized void executeUpdate(){ o&>0
pc
Connection conn=null; 4gYP .h:,
PreparedStatement ps=null; 0[PP-]JS
try{ EqOB
0\
conn = DBUtils.getConnection(); '-
Z4GcL
conn.setAutoCommit(false); Y<{j':
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "e_ED*
for(int i=0;i<CountCache.list.size();i++){ \TKv3N
CountBean cb=(CountBean)CountCache.list.getFirst(); 02S Uyv(Mt
CountCache.list.removeFirst(); 9 /9,[ A
ps.setInt(1, cb.getCountId()); n%ld*EgY
ps.executeUpdate();⑴ Uqkh@-6-
//ps.addBatch();⑵ )Dv"seH.
} p,xM7V"O)
//int [] counts = ps.executeBatch();⑶ `_f3o,5
conn.commit(); 5uu{f&?u)
}catch(Exception e){ ntjUnd&v\
e.printStackTrace(); <,LeFy\zW
} finally{ ,x_g|J _Y
try{ SK-|O9Ki
if(ps!=null) { z`TI<B
ps.clearParameters(); IQH;`+
ps.close(); E
fqa*,k
ps=null; h>\}-|Ek
} smWA~Aq
}catch(SQLException e){} bf}r8$,
DBUtils.closeConnection(conn); U:`rNHl
} "+|>nA=7
} 0V1kZ.
public long getLast(){ u0i
@.
return lastExecuteTime; @GGyiK@
} 60hf)er
public void run(){ F.O2;M|x
long now = System.currentTimeMillis(); jP+4'O!s[
if ((now - lastExecuteTime) > executeSep) { 'o5[:=K
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^ 41p+
//System.out.print(" now:"+now+"\n"); $bD!./fl
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); FxD" z3D
lastExecuteTime=now; <KJ18/
executeUpdate(); CMTy(Z8_)
} 5ptbz<Xv
else{ |z5olu$gVc
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); K_RrSI&>
} F.AO
} /wIZ '
} I\4I,ds
//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 ]Q^oc
^B5Hjf9
类写好了,下面是在JSP中如下调用。 #Xsby
{x-g?HB
<% 1tg
CountBean cb=new CountBean(); 3aW4Gs<g
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); />]/At
CountCache.add(cb); 0k3^+#J
out.print(CountCache.list.size()+"<br>"); 64zO%F*
CountControl c=new CountControl(); W/J3sAYv
c.run(); _gU[FUBtJ
out.print(CountCache.list.size()+"<br>"); =. OWsFv
%>