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: ?$o8=h
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CountBean.java c
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/* ; id
* CountData.java `yxk
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* `HHbQXB
* Created on 2007年1月1日, 下午4:44 K&S~IFy
* $i3/||T,9
* To change this template, choose Tools | Options and locate the template under zKI(yC
* the Source Creation and Management node. Right-click the template and choose I=b#tUBh8
* Open. You can then make changes to the template in the Source Editor. L=VuEF
*/ W`;E-28Dg
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package com.tot.count; nhy3E
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/** aUJ&
* M ,<%j
* @author zg^5cHP\
*/ %u!#f<"[
public class CountBean { m2 OP=z@)
private String countType; {wd.aUB
int countId; 2Yyc`o0R;h
/** Creates a new instance of CountData */ 6vmkDL8{A8
public CountBean() {} 8IVKS>
public void setCountType(String countTypes){ t<$yxD/R
this.countType=countTypes; )ll}hGS
} =JEnK_@?K\
public void setCountId(int countIds){ &yYK%~}t[
this.countId=countIds; fE M8/bhq
} ^D6 JckW
public String getCountType(){ BI}>"',
return countType; =n$,Vv4A
} &;,w})
public int getCountId(){ <FGM/e4
return countId; gmrjCLj
} KUB"@wUr
} <6Br]a60RR
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CountCache.java ~C[R%%Gu
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/* Kw'A%7^e
* CountCache.java RMsr7M4<91
* TCB<fS~U-
* Created on 2007年1月1日, 下午5:01 KaO8rwzDN
* zQ7SiRt7*
* To change this template, choose Tools | Options and locate the template under _a c_8m
* the Source Creation and Management node. Right-click the template and choose Fnr*.k
* Open. You can then make changes to the template in the Source Editor. ,A_itRHH
*/ 4R^'+hy|?
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package com.tot.count; DGp'Xx_8
import java.util.*; 7 +?
/** A*@!tz<
* lK}F>6^\
* @author "bC8/^
*/ ?2Bp^3ytJ
public class CountCache { !dmI}<@&k
public static LinkedList list=new LinkedList(); 1{"e'[L
/** Creates a new instance of CountCache */ Lw-)ijBW
public CountCache() {} LkJ3 :3O
public static void add(CountBean cb){ b7HS3NYk
if(cb!=null){ IDcu#Nz`
list.add(cb); (swP#t5S
} 0*h\/!e
} JTdK\A>l
} KLbP;:sr
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CountControl.java {T=I~#LjMI
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/* F4d L{0;j
* CountThread.java O4(
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* t t#M4n@
* Created on 2007年1月1日, 下午4:57 g_.BJ>Uv
* hC~lH eH
* To change this template, choose Tools | Options and locate the template under U<o,`y[Tn
* the Source Creation and Management node. Right-click the template and choose 00<iv"8
* Open. You can then make changes to the template in the Source Editor. )|\72Z~eq
*/ Lv#DIQ8y
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package com.tot.count; :0#!=
import tot.db.DBUtils; eF:6k qg
import java.sql.*; G4ZeO:r
/** 8`'_ckIgr
* RYmk6w!w
* @author 1G$kO90
*/ 6rdm=8WFA
public class CountControl{ }LQ&AIRN
private static long lastExecuteTime=0;//上次更新时间 "jb?P$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 \'j%q\Bl;
/** Creates a new instance of CountThread */ 5AQ $xm4
public CountControl() {} 'J+Vw9s7
public synchronized void executeUpdate(){ >m%\SuXq
Connection conn=null; YdIV_&-W
PreparedStatement ps=null; ;J2=6np
try{ ^'[Rb!Q8
conn = DBUtils.getConnection(); `P"-9Ue=
conn.setAutoCommit(false); R (4 :_ xc
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); {Pu\KRU
for(int i=0;i<CountCache.list.size();i++){ |PTL!>ym2
CountBean cb=(CountBean)CountCache.list.getFirst(); G8eAj%88
CountCache.list.removeFirst(); #jK{)%}mA
ps.setInt(1, cb.getCountId()); yQ6{-:`)
ps.executeUpdate();⑴ !d%OoRSU'
//ps.addBatch();⑵ ~M,nCG^4
} /zPN9 db
//int [] counts = ps.executeBatch();⑶ f`H}Y!W(
conn.commit(); 6-<,1Q'D
}catch(Exception e){ Gz$DsaG
e.printStackTrace(); eH79,!=2
} finally{ %xkqiI3Ff
try{ P4ot,Q4
if(ps!=null) { Y{um1)k
ps.clearParameters(); 0Tg/R4dI
ps.close(); a&4>xZU #
ps=null; ejD;lvf
} En-eG37l
}catch(SQLException e){} = DvnfT<
DBUtils.closeConnection(conn); sj
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} 3E:wyf)i"
} A+NLo[swwu
public long getLast(){ D",ZrwyJ
return lastExecuteTime; W<v?D6dFq
} 0M-Zp[w\-
public void run(){ X~%Wg*Hm
long now = System.currentTimeMillis(); 0 UjT<t^F
if ((now - lastExecuteTime) > executeSep) { d v"
//System.out.print("lastExecuteTime:"+lastExecuteTime); lOcvRF
//System.out.print(" now:"+now+"\n"); ogDyrY}]
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); OZ$u&>916
lastExecuteTime=now; t9W_ [_a9
executeUpdate(); Vz51=?75
} js'*:*7
else{ Xpjk2 [,
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ub./U@1
} cM.q^{d`
} K|E}Ni
} [Gy sx
//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 BX2&tQSp
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类写好了,下面是在JSP中如下调用。 03AYW)"}M
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<% P[aB}<1f0
CountBean cb=new CountBean(); Vad(PS0
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ~Og'IRf
CountCache.add(cb); IiS1ubNtZ
out.print(CountCache.list.size()+"<br>"); :n{rVn}G
CountControl c=new CountControl(); @ U:WWTzf
c.run(); sw8Ic\vT
out.print(CountCache.list.size()+"<br>"); o#Rao#bD:
%>