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: /X9K g
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CountBean.java \mbm$E+X
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/* }f?$QSF
* CountData.java W&T-E,
* XE6sFU
* Created on 2007年1月1日, 下午4:44 .SAOE'Foo
* Lzm9Kh;
* To change this template, choose Tools | Options and locate the template under ER;?[!
* the Source Creation and Management node. Right-click the template and choose :G!i]1x<
* Open. You can then make changes to the template in the Source Editor. . =yF
*/ Hyh$-iCa
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package com.tot.count; x2%xrlv<J/
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/** o'+p,_y9Y@
* S ( e]@
* @author DI"KH)XD
*/ vtk0 j
public class CountBean { /m"O.17N
private String countType; `bY>f_5+
int countId; 8eGq.+5G
/** Creates a new instance of CountData */ k[#<=G_=/E
public CountBean() {} ae_Y?g+3
public void setCountType(String countTypes){ Z8IY!d
this.countType=countTypes; 4L)#ku$jW
} Qu"zzb"k
public void setCountId(int countIds){ ' d' Dlg
this.countId=countIds; 0@7%
} }M7{~ov#s
public String getCountType(){ "tdF#>x
return countType; {wA(%e3_
} pL2P
.
public int getCountId(){ @
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return countId; ~XU%_Hz
} y=.`:EB9b
} ktF\f[
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CountCache.java C%&A9(jG
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/* w5Lev}Rb
* CountCache.java ? DJ/Yw>>3
* OYW:I1K<5
* Created on 2007年1月1日, 下午5:01 &UrPb%=2H
* \Hb"bv
* To change this template, choose Tools | Options and locate the template under :O)\+s-
* the Source Creation and Management node. Right-click the template and choose q#D-}R_RN
* Open. You can then make changes to the template in the Source Editor. 5NGQWg
*/ inQ1$
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package com.tot.count; ]"q9 ~
import java.util.*; V?t56n Y}
/** i=3~ h Zl
* c6-~PKJL
* @author 9 n0?0mk
*/ ?$$Xg3w_#
public class CountCache { -,:^dxE'
public static LinkedList list=new LinkedList(); }ZqnsLu[)
/** Creates a new instance of CountCache */ )?y${T
public CountCache() {} }jdMo83
public static void add(CountBean cb){ @qUgp*+{
if(cb!=null){ \0j-p
list.add(cb); 8SGqDaRt
} ]Xm+-{5?!R
} ExKyjWAJ
} >uLWfk+y1
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CountControl.java ^ruz-N^Y!
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/* 3R>"X c
* CountThread.java /0m0""
* aoUz_7
* Created on 2007年1月1日, 下午4:57 `_"loPu
* "50c<sZSB
* To change this template, choose Tools | Options and locate the template under *(g0{V
* the Source Creation and Management node. Right-click the template and choose eL" +_lW
* Open. You can then make changes to the template in the Source Editor. 3QhQpPk),
*/ k^@dDLr"
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package com.tot.count; .~O-
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import tot.db.DBUtils; A'6-E{
import java.sql.*; "UYlC0 S\
/** HkPdqNC&
* n:"0mWnL$y
* @author !-HJ%(5:F
*/
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public class CountControl{ :lU#Dm]
private static long lastExecuteTime=0;//上次更新时间 0}mVP
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 gT_tR_g
/** Creates a new instance of CountThread */ h~pQ
public CountControl() {} 6c6w w"
public synchronized void executeUpdate(){ 9;Qgby
Connection conn=null; #J'V,_wH
PreparedStatement ps=null; 7TtDI=f
try{ yz7Fe
conn = DBUtils.getConnection(); 7u`:e,'
conn.setAutoCommit(false); Og-v][
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); W"!{f
for(int i=0;i<CountCache.list.size();i++){ hsAk7KC
CountBean cb=(CountBean)CountCache.list.getFirst(); sa?s[
CountCache.list.removeFirst(); .^xQtnq
ps.setInt(1, cb.getCountId()); Z~AgZM
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ps.executeUpdate();⑴ laRn![[
//ps.addBatch();⑵ #EA` |
} a9_KoOa.H
//int [] counts = ps.executeBatch();⑶ uOAd$;h@_Z
conn.commit(); ~KYA{^`*
}catch(Exception e){ M 4E|^p=5
e.printStackTrace(); De
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} finally{ ku)/
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try{ kO/YO)g
if(ps!=null) { SuA
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ps.clearParameters(); cO8yu`4!e
ps.close(); B7.<A#y2
ps=null; %RX!Pi}5+g
} :#OaE,
}catch(SQLException e){} 9K>~9Za
DBUtils.closeConnection(conn); zeshM8=
} 5cj&D74o
} O/.8;.d;4Y
public long getLast(){ LFAefl\
return lastExecuteTime; G%fXHAs .+
} g;~$xXn
public void run(){ .U#oN_D
long now = System.currentTimeMillis(); Z|B`n
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if ((now - lastExecuteTime) > executeSep) { Gs/G_E(T
//System.out.print("lastExecuteTime:"+lastExecuteTime); SveP:uJA[
//System.out.print(" now:"+now+"\n"); emHaZhh
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); p
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lastExecuteTime=now; e7yn"kd
executeUpdate(); /Yj; '\3
} pS "A{k)i
else{ W'PW;.,
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); =j%ORD[
} O[8wF86R
} )}J}d)
} TB_OFbI2
//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 =, 64Qbau
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类写好了,下面是在JSP中如下调用。 yujv^2/
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<% z(#CO<C.t
CountBean cb=new CountBean(); J;k8 a2$_
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); E J&w6),d
CountCache.add(cb); h
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out.print(CountCache.list.size()+"<br>"); =%S*h)}@
CountControl c=new CountControl(); YRu/KUT$ 7
c.run(); -sx=1+\nf
out.print(CountCache.list.size()+"<br>"); .7HEI;4
%>