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: m`$>:B
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CountBean.java 6B''9V:s
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/* m*!f%}T
* CountData.java 4C1FPrh
* k=7Gr;;l=p
* Created on 2007年1月1日, 下午4:44 *w/WHQ`xI
* /u)Rppu
* To change this template, choose Tools | Options and locate the template under :B=8_M
* the Source Creation and Management node. Right-click the template and choose NGD*ce"w
* Open. You can then make changes to the template in the Source Editor. Q0cY/'>4
*/ ck+b/.gw`
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package com.tot.count; tKZ&1E
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/** ISS\uj63M
*
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* @author |=cCv_y
*/ zBt`L,^
public class CountBean { :,kU#eZ$-
private String countType; 9&%#nN4`8
int countId; n}A?jOSAe
/** Creates a new instance of CountData */ xHB/]Vd-
public CountBean() {} o-~~,n\
public void setCountType(String countTypes){ 8PBU~mr
this.countType=countTypes; r!$'!lCR
} nG"n-$A?<
public void setCountId(int countIds){ !&`}]qQZ
this.countId=countIds; f<89$/w
} ^Cg^`n?@b
public String getCountType(){ e3eVvl5]
return countType; ejklpa ./
} $(gGoL<
public int getCountId(){ fpvvV(
return countId; 1OJ*wI*
} |mxNUo-
} 3Q"F(uE v^
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CountCache.java w<65S
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/* 5g``30:o
* CountCache.java WRD
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* [5Fd P0
* Created on 2007年1月1日, 下午5:01 >?5xDbRj
* Sty!atEWT
* To change this template, choose Tools | Options and locate the template under jJ
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* the Source Creation and Management node. Right-click the template and choose lwOf)jK:J
* Open. You can then make changes to the template in the Source Editor. u#+RUtM
*/ 9g
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package com.tot.count; Xsd$*F@<
import java.util.*; \+k, :8s/
/** r<*O
* l"J*)P
* @author 6F`qi:a+
*/ YwL`>?
public class CountCache { pe()f/Jx(
public static LinkedList list=new LinkedList(); TMJ9~"IO
/** Creates a new instance of CountCache */ )N(9pnyZH
public CountCache() {} LJGJ|P
public static void add(CountBean cb){ b~_B
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if(cb!=null){ N = LM?(H
list.add(cb); 9Ct_$.Q.
} W+gpr|R2
} 4xm&pQo{V6
} '>3`rsu
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CountControl.java &%^K,Q"
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/* ]9jZndgC
* CountThread.java __!m*!sd
* Y@Y`gF6F
* Created on 2007年1月1日, 下午4:57 Ic'Q5kfM
* ll^DY
hx}
* To change this template, choose Tools | Options and locate the template under XHxz @_rw
* the Source Creation and Management node. Right-click the template and choose 90~*dNk
* Open. You can then make changes to the template in the Source Editor. -~
0] 7Cpl
*/ {6'*Phw
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package com.tot.count; 0
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import tot.db.DBUtils; .f>,6?
import java.sql.*; cd!|Ne>fe
/** .nEs:yn
* kMy<G8 s
* @author 2 H[ ; v +
*/ {Eu'v$c!
public class CountControl{ T2wv0sHlt
private static long lastExecuteTime=0;//上次更新时间 IX9K.f
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0[/vQ+O ]2
/** Creates a new instance of CountThread */ -kl;!:'.3
public CountControl() {} 14H'!$
public synchronized void executeUpdate(){ 3gpo
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Connection conn=null; c45tmul
PreparedStatement ps=null; sAi&A9"*
try{ `(!NYx
conn = DBUtils.getConnection(); 6lsL^]7
conn.setAutoCommit(false); *>k!hq;j
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $A`xhh[
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); W,3zL.qH"
CountCache.list.removeFirst(); lEHwZ<je
ps.setInt(1, cb.getCountId()); /xySwSmh3
ps.executeUpdate();⑴ 3 > |uF
//ps.addBatch();⑵ -Q$b7*"z(
} KAed!z9
//int [] counts = ps.executeBatch();⑶ 'M8aW!~
conn.commit(); Wr5 Q5s)c
}catch(Exception e){ hK(tPl$
e.printStackTrace(); vU!8`x)
} finally{ :.$"kXm^
try{ ?;
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if(ps!=null) { )lh8
k{
ps.clearParameters(); IaLMWoh
ps.close(); V&i2L.{G)
ps=null; *69c-`o
} j0FW8!!-g
}catch(SQLException e){} R&#tSL
DBUtils.closeConnection(conn); 7^MX l
} zDDK
} P16YS8$
public long getLast(){ BwxnDe G)
return lastExecuteTime; _A 2Lv]vfV
} jWvtv ng
public void run(){ JrDHRIkgm
long now = System.currentTimeMillis(); B3mS]
if ((now - lastExecuteTime) > executeSep) { \D?:J3H*]
//System.out.print("lastExecuteTime:"+lastExecuteTime); ~*}$>@f{[X
//System.out.print(" now:"+now+"\n"); tPU-1by$
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); bLbR IY"l
lastExecuteTime=now; 6tn+m54_
executeUpdate(); sTkkM9
} vXdZmYrC
else{ X|b2c+I
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Oz{%k#X-
} Qz+sT6js-
} NZk&JND
} ]JjK#eh
//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 :.uk$jx
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类写好了,下面是在JSP中如下调用。 Es.nHN^]%K
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<% J}TfRrf
CountBean cb=new CountBean(); y+U83a[L*
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); q[d)e6
CountCache.add(cb); _D,eyP9P
out.print(CountCache.list.size()+"<br>"); +xp]:h|
CountControl c=new CountControl(); | o0RP|l
c.run(); Hi7y(h?wj
out.print(CountCache.list.size()+"<br>"); :#u}.G
%>