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: V+cHL
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CountBean.java 3[aCy4O
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/* ep>S$a*|
* CountData.java U!^\DocAY
* fMI4'.Od
* Created on 2007年1月1日, 下午4:44 W UDQb5k
* cYmMO[4YG'
* To change this template, choose Tools | Options and locate the template under l+y/ Mq^QB
* the Source Creation and Management node. Right-click the template and choose :Y~fPke
* Open. You can then make changes to the template in the Source Editor. IHMZE42
*/ Z/6B[,V
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package com.tot.count; ZGe+w](
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/** &*/8Ojv)9
* 7AHEzJh"
* @author [:TOU^
*/ Bp>%'L
public class CountBean { ``$At ,m
private String countType; *5.s@L( VU
int countId; =H3 JRRS
/** Creates a new instance of CountData */ OGrp{s
public CountBean() {} N:\I]M
public void setCountType(String countTypes){ ;v*$6DIC5
this.countType=countTypes; K zKHC
} b.Z K1
public void setCountId(int countIds){ HG5|h[4Gt
this.countId=countIds; 0:Yz'k5
} 3RZP 12x
public String getCountType(){ s>76?Q:i
return countType; <0k(d:H-
} M
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public int getCountId(){ K({+3vK
return countId; WDWb7
} ?&pjP,a
} 9)3ok#pQ/
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CountCache.java Vq -!1.v3
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/* /{\tkvv-Z
* CountCache.java >A7),6
* a>(LFpVk}
* Created on 2007年1月1日, 下午5:01 !2>gC"$nv
* |9{l8`9}_
* To change this template, choose Tools | Options and locate the template under Z,!
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* the Source Creation and Management node. Right-click the template and choose g\OPidY
* Open. You can then make changes to the template in the Source Editor. AhiZ0W"
*/ CJ%bBL'.
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package com.tot.count; $DJp|(8
import java.util.*; +^1HtI|y
/** ~^w;`~L
* L'`W5B@
* @author ]SFB_5Gb
*/ GGo
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public class CountCache { `LEk/b1(P
public static LinkedList list=new LinkedList(); (iIJ[{[H4)
/** Creates a new instance of CountCache */ GL(R9Y
public CountCache() {} c{ +Y$
public static void add(CountBean cb){ i$?i1z*c}
if(cb!=null){ XTXRC$B
list.add(cb); RYZh"1S;k
} pMHY2t
} TGY^,H>J
} ICTl{|i ]
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CountControl.java P"cc$lB~ I
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/* #E3Y;
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* CountThread.java aqK<}jy
* iL\<G}
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* Created on 2007年1月1日, 下午4:57 &$ia#j{l
* C6Ap
4
* To change this template, choose Tools | Options and locate the template under jt@k<#h~
* the Source Creation and Management node. Right-click the template and choose P`v%<
9~
* Open. You can then make changes to the template in the Source Editor. Sx5r u?$.
*/ >}\!'3)_
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package com.tot.count; hp/}Z"A=
import tot.db.DBUtils; & ;ie+/B
import java.sql.*; =mxmJFA
/** vq
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* lBvQ?CJ<y
* @author .ZJt
*/ sF:3|Yy0
public class CountControl{ ZXsm9
private static long lastExecuteTime=0;//上次更新时间 U{"&Jj
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Wo<zvut8
/** Creates a new instance of CountThread */ m/5:-xL31
public CountControl() {} EGf9pcUEO&
public synchronized void executeUpdate(){ rQC{"hS1
Connection conn=null; -5l74f!i
PreparedStatement ps=null; *6cP-Vzd
try{ qY]IX9'kV
conn = DBUtils.getConnection(); cxFfAk\,en
conn.setAutoCommit(false); cfyN)#9
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); M;ac U~J
for(int i=0;i<CountCache.list.size();i++){ =5a~xlBjD
CountBean cb=(CountBean)CountCache.list.getFirst(); Q+*o-
CountCache.list.removeFirst(); d}GO(
ps.setInt(1, cb.getCountId()); '=EaZ>=
ps.executeUpdate();⑴ H1N_
//ps.addBatch();⑵ Edj}\e*-J
} \::<]
//int [] counts = ps.executeBatch();⑶ V/j+Z1ZW
conn.commit(); 7z9gsi
}catch(Exception e){ R;,+0r^i
e.printStackTrace(); 7rw}q~CE5
} finally{ 7Co
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try{ lwIU|T<4
if(ps!=null) { 6 :K~w<mMJ
ps.clearParameters(); I9h?Z&n5
ps.close(); D0/ \
ps=null; /[`bPKr
} i|0H {q
}catch(SQLException e){} 2u4aCfIx
DBUtils.closeConnection(conn); CS"2Sd 1`
} y+\nj3v6
} @[D-2s
public long getLast(){ eVL'Ao&Ho
return lastExecuteTime; a]|P rjPI
} `So*\#\T
public void run(){ &uI`Xq.
long now = System.currentTimeMillis(); _V^^%$
if ((now - lastExecuteTime) > executeSep) { 3N|,c]|
//System.out.print("lastExecuteTime:"+lastExecuteTime); T.HS.
//System.out.print(" now:"+now+"\n"); x>m_ v
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?ntyF-n&
lastExecuteTime=now; yeqZPzn
executeUpdate(); W6_/FkO
} (0g@Z`r
else{ YQxVeS(
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); sqFMO+
} ";AM3
} LRW7_XYz
} (?Fz{
//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 yxh8sAZ
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类写好了,下面是在JSP中如下调用。 TXD\i Dq
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<% JL45!+
CountBean cb=new CountBean(); (dv Cejc^p
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "l6v[yv
CountCache.add(cb); xG@zy4
out.print(CountCache.list.size()+"<br>"); .YKqYN?y4
CountControl c=new CountControl(); C
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c.run(); w?|gJ*B"
out.print(CountCache.list.size()+"<br>"); WDNuR#J?
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