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: 8X=cGYC#
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CountBean.java ^6!C":f
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/* s`*
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* CountData.java k9j_#\E[
* `}:q@:%
* Created on 2007年1月1日, 下午4:44 Jz D
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* W:q79u yX
* To change this template, choose Tools | Options and locate the template under 5t]}(.0+
* the Source Creation and Management node. Right-click the template and choose qms+s~oA
* Open. You can then make changes to the template in the Source Editor. qbjBN z
*/ Ov1$7 r@
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package com.tot.count; Ad)Po
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/** %4#,y(dO
* rj[2XIO
* @author L(a&,cdh
*/ P( >*gp
public class CountBean { w=EUwt
private String countType; {@Y|"qIN
int countId; h8;B +#f`
/** Creates a new instance of CountData */ &jCT-dj
public CountBean() {} * z|i{=W
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public void setCountType(String countTypes){ Wx#((T
this.countType=countTypes; fUQuEh5_
} q[4{Xh
public void setCountId(int countIds){ \F]X!#&+
this.countId=countIds; ,L#Qy>MOb
} [Nb0&:$ay
public String getCountType(){ OE87&Cl"{t
return countType; '>[l1<d!G
} CW*Kdt
public int getCountId(){ ]H8CVue
return countId; CZB!vh0
} Qs2E>C
} mm-!UsT
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CountCache.java O9OD[VZk
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/* Xd%c00"U
* CountCache.java !mNXPqnN
* m&/{iCwp
* Created on 2007年1月1日, 下午5:01 VU+` yQp
* IXb]\ )
* To change this template, choose Tools | Options and locate the template under 68ce+|
* the Source Creation and Management node. Right-click the template and choose f8`K8Y]4
* Open. You can then make changes to the template in the Source Editor. ,at"Q$)T
*/ x)eYqH~i
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package com.tot.count; K_/8MLJQ
import java.util.*; $qkVu
/** s%h|>l[lKT
* R?"sM<3`e
* @author P7GuFn/p~2
*/ zbH Nj(~
public class CountCache { ;J|sH>i
public static LinkedList list=new LinkedList(); JmDi{B?
/** Creates a new instance of CountCache */ j^ L"l;m
public CountCache() {} Cz=HxU80J
public static void add(CountBean cb){ E$5)]<p! <
if(cb!=null){ dQ6:c7hp>D
list.add(cb); >ZMB}pt`
} 4;anoqiG\
} XWH{+c"
} Il(p!l<Xz#
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CountControl.java _`yd"0Ux
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/* _ndc^OG
* CountThread.java ZH8O%>!
* V<~.:G$3H
* Created on 2007年1月1日, 下午4:57 <<#-IsT
* _'9("m V
* To change this template, choose Tools | Options and locate the template under OO?d[7Wt0
* the Source Creation and Management node. Right-click the template and choose =O= 0 D
* Open. You can then make changes to the template in the Source Editor. :s8^nEK
*/ oej5bAi
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package com.tot.count; r*#ApM"L
import tot.db.DBUtils; V1Yab#
import java.sql.*; :1h1+b@,
/** ~R7F[R
* 7_Yxz$m
* @author eF]`?AeWQ
*/ P{YUW~
public class CountControl{ GE;S5X]X
private static long lastExecuteTime=0;//上次更新时间 H#pl&/+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g)7~vm2/,
/** Creates a new instance of CountThread */ 3vx5dUgl,
public CountControl() {} )?35!s6
public synchronized void executeUpdate(){ AF ,*bb
Connection conn=null; Rf *we+
PreparedStatement ps=null; RTN?[`
try{ l1 (6*+
conn = DBUtils.getConnection(); ~JjL411pG
conn.setAutoCommit(false); 2'O2n]{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); EfxW^zm)
for(int i=0;i<CountCache.list.size();i++){ RL Beti>
CountBean cb=(CountBean)CountCache.list.getFirst(); x*}41;j}C
CountCache.list.removeFirst(); <9zzjgzG{c
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ %UIR GI
//ps.addBatch();⑵ ~)!yl. H
} ~)5NX
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//int [] counts = ps.executeBatch();⑶ 8<BYAHY^
conn.commit(); 2tz%A~}4
}catch(Exception e){ p;;4b@
e.printStackTrace(); USF9sF0l
} finally{ Lhg4fuos@)
try{ ckR>ps[ u
if(ps!=null) { L $R"?O7
ps.clearParameters(); }xZR`xP(
ps.close(); +NML>g#F~z
ps=null; ra87~kj<
} 8 xfn$
}catch(SQLException e){} Y0nnn
DBUtils.closeConnection(conn); ITcgpK6k
} MBy0Ky
} L=`QF'Im
public long getLast(){ *nb `DR
return lastExecuteTime; <2b&AF{En
} F@m]Imn5Dx
public void run(){ O&DkB*-
long now = System.currentTimeMillis(); 7Mx F?
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if ((now - lastExecuteTime) > executeSep) { Gn*cphb
//System.out.print("lastExecuteTime:"+lastExecuteTime); ]=X6*
E*/E
//System.out.print(" now:"+now+"\n"); s98Jh(~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ;#'YO1`gf3
lastExecuteTime=now; ,1xX`:
executeUpdate(); #cHH<09rl
} 9o)sSaTx=
else{ UoDS)(i
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Q7<%_a
} ;E,^bt<U
} G$#Q:]N
} 2xPkQOj3
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 _=%F6}TE
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类写好了,下面是在JSP中如下调用。 %S$P<nKN5
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<% WBb@\|V|
CountBean cb=new CountBean(); L7kNQ/
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); qp#Is{=m
CountCache.add(cb); 36]pE<
out.print(CountCache.list.size()+"<br>"); \!O3]k,r
CountControl c=new CountControl(); UA>3,|gV1
c.run(); i}&&rr
out.print(CountCache.list.size()+"<br>"); \"]KF8c^_
%>