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: E!l!OtFL
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CountBean.java ,TN
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/* SO(NVJh
* CountData.java Dq5j1m.
* FrYqaP
* Created on 2007年1月1日, 下午4:44 p@5`&Em,
* =&2Lb
* To change this template, choose Tools | Options and locate the template under ^,_w$H
* the Source Creation and Management node. Right-click the template and choose `A^"%@j
* Open. You can then make changes to the template in the Source Editor. ,5,!es@`b
*/ E}p&2P+MR
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package com.tot.count; 2h1C9n%j9
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/** +hT:2TXn
* )oPLl|=h
* @author /bi[e9R
*/ \LppYXz
public class CountBean { Q/_f
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private String countType; `-l6S
int countId; DhT>']Z
/** Creates a new instance of CountData */ v` 7RCg`
public CountBean() {} ie\"$i.98H
public void setCountType(String countTypes){ $[&*Bj11Yg
this.countType=countTypes; PuT@}tw
} %i-c0|,T4
public void setCountId(int countIds){ _m'Fr
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this.countId=countIds; r{ef .^&:
} ~ZhraSI)G
public String getCountType(){ Hp|_6hO 2
return countType; 4 G-wd
} fhp<oe>D
public int getCountId(){ qI<mjB{3`
return countId; #=f?0UTA
} H{k^S\K
} *
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CountCache.java xp72>*_9&
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/* ); dT_
* CountCache.java y_IM@)1H~
* yo)%J
* Created on 2007年1月1日, 下午5:01 R_7 d@FQ1
* \":m!K;Z
* To change this template, choose Tools | Options and locate the template under &8_gRP
* the Source Creation and Management node. Right-click the template and choose G *;a^]-
* Open. You can then make changes to the template in the Source Editor. 1ilBz9x*!
*/ ;Q[mL(1:
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package com.tot.count; z3M6V}s4
import java.util.*; I*kK 82
/** %r6y
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* c|62jY"$-2
* @author *2Ht&
*/ C{DvD'^
public class CountCache { Dzs[GAQ]
public static LinkedList list=new LinkedList(); YY!6/5*/]
/** Creates a new instance of CountCache */ c 8>hcV
public CountCache() {} S9`flo
public static void add(CountBean cb){ e\JojaV
if(cb!=null){ Pgus42f%
list.add(cb); O1*NzY0Y%-
} Kt|1&Gk
} /_Z652@
} K7Wk6Aw
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CountControl.java iN0nw]_*
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/* -'BA{#e}L
* CountThread.java $.v5~UGb{\
* yz*6W
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* Created on 2007年1月1日, 下午4:57 UHxE)]J
* MR<;i2p
* To change this template, choose Tools | Options and locate the template under a5!Fv54
* the Source Creation and Management node. Right-click the template and choose $3uKw!z
* Open. You can then make changes to the template in the Source Editor. :2-pjkhiwY
*/ R&';Oro
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package com.tot.count; xD[Gq%
import tot.db.DBUtils; /iV}HV0
import java.sql.*; hcbv;[bG
/** A\#P*+k 0
* S'B|>!z@
* @author Xo*%/0q'
*/ _({A\}Q|
public class CountControl{ mJ`A_0
private static long lastExecuteTime=0;//上次更新时间 G0;XaL:
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 _}VloiY
/** Creates a new instance of CountThread */ ?Wt$6{)
public CountControl() {} *`Yv.=cd
public synchronized void executeUpdate(){ JEgx@};O
Connection conn=null; Ox'/`Mppw
PreparedStatement ps=null; >P $;79<
try{ /<8N\_wh
conn = DBUtils.getConnection(); `zt_7MD
conn.setAutoCommit(false); Vy,^)]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;~u{56
for(int i=0;i<CountCache.list.size();i++){ k{$ ao
CountBean cb=(CountBean)CountCache.list.getFirst(); (%o2jroQ#
CountCache.list.removeFirst(); ku
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ps.setInt(1, cb.getCountId()); 0}xFD6{X
ps.executeUpdate();⑴ k`p74MWu
//ps.addBatch();⑵ |7pR)KH3
} \Z/)Y;|mi0
//int [] counts = ps.executeBatch();⑶ *"r~-&IL
conn.commit(); o9S+6@
}catch(Exception e){ Kmv+1T0,
e.printStackTrace(); S&Ee,((E(
} finally{ d)R352
try{ v\"S
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if(ps!=null) { ?9=9C"&s
ps.clearParameters(); 0{PzUIM,W
ps.close(); n[,w f9
ps=null; t2iv(swTe
} _fP&&}
}catch(SQLException e){} `VL}.h
DBUtils.closeConnection(conn); ^3FE\V/=
} [wB9s{CX
} ]UG*r%9
public long getLast(){ g}U3y'
return lastExecuteTime; la?Wnw
} Q\,o:ZU_
public void run(){ TbF4/T1b
long now = System.currentTimeMillis(); |xvy')(b
if ((now - lastExecuteTime) > executeSep) { 0%
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//System.out.print("lastExecuteTime:"+lastExecuteTime); <ExZ:ip
//System.out.print(" now:"+now+"\n"); tpTAeQ*:d
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); I]y.8~xs
lastExecuteTime=now; 3 Lsj}p
executeUpdate(); 1#4PG'H
} cl*PFQp9j
else{ @M8|(N%
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~|AwN [
} r]Ff{la5
} @hImk`&[N
} #vqo -y7@
//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 KyO8A2'U
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类写好了,下面是在JSP中如下调用。 =FT98H2*|
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<% {gaai
CountBean cb=new CountBean(); ?[MsQQd~
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); tDCw-
CountCache.add(cb); `[YngYw
out.print(CountCache.list.size()+"<br>"); }O4se"xK
CountControl c=new CountControl(); $eBX
c.run(); `O8b1-1q~
out.print(CountCache.list.size()+"<br>"); eVcANP
%>