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>V8|Hz;
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CountBean.java TOuFFR
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/* =q"3a9pb7
* CountData.java -0\$JAyrx
* [D?E\Nkk
* Created on 2007年1月1日, 下午4:44 ?4~lA
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* 6a,YxR\
* To change this template, choose Tools | Options and locate the template under W@0(Y9jdg
* the Source Creation and Management node. Right-click the template and choose <n`|zQ
* Open. You can then make changes to the template in the Source Editor. !{3pp
*/ &`%C'KZ
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package com.tot.count; BW*zj=N%
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/** 2Vi[qS^
* l:[=M:#p
* @author P~*fZ)\}F@
*/ bBQp:P?E
public class CountBean {
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private String countType; d8K^`k+x
int countId; P"#^i<ut@T
/** Creates a new instance of CountData */ " h#=ctCx"
public CountBean() {} BxG;vS3>*e
public void setCountType(String countTypes){ /[-hJ=<Yb
this.countType=countTypes; >ylVES/V
} 3A9|{Vaz+6
public void setCountId(int countIds){ Q7s1M&K
this.countId=countIds; > w'6ZDA*X
} 8;5/_BwMu
public String getCountType(){ _96&P7
return countType; 5-J-Tn
} +(<f(]bG
public int getCountId(){
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return countId; r5"/EMieh
} yqU++;6
} ~Mx
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CountCache.java v 3NaX.
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/* g,;MV7yE
* CountCache.java JB|I/\(A
* B?M+`;
* Created on 2007年1月1日, 下午5:01 y/FisX
* F~Li.qF
* To change this template, choose Tools | Options and locate the template under We ->d |=
* the Source Creation and Management node. Right-click the template and choose oK>,MdB
* Open. You can then make changes to the template in the Source Editor. t&xx-4
*/ s5pY)6)
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package com.tot.count; 2*M*<p=v
import java.util.*; x\%egw
/** xv:?n^yt.[
* jBC9Vt;B
* @author aI<~+ ]
*/ 1gE`_%?K
public class CountCache { bm4W,
public static LinkedList list=new LinkedList(); 1mX*0>
/** Creates a new instance of CountCache */ 1 W0; YcT]
public CountCache() {} 0D'Wr(U(
public static void add(CountBean cb){ TU/J]'))C
if(cb!=null){ Vo%d;>!G\;
list.add(cb); )=D&NO67Pq
} b>i=",i\
} nqBuC
} /\#5\dHj
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CountControl.java @K9T )p]
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/* Y[!a82MTzn
* CountThread.java I?K0bs+6
* cGp^;> ]M
* Created on 2007年1月1日, 下午4:57
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* p{rS -`I
* To change this template, choose Tools | Options and locate the template under xeI{i{8
* the Source Creation and Management node. Right-click the template and choose "YL-!P
* Open. You can then make changes to the template in the Source Editor. :3B\,inJ
*/ $c}0L0
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package com.tot.count; a%dx\&K
import tot.db.DBUtils; pd#/;LT
import java.sql.*; b5DrwX{Ff
/** L,6Y=?
* HhL%iy1
* @author 0U>Q<I}
*/ V%ch'
public class CountControl{ =lwS\mNs
private static long lastExecuteTime=0;//上次更新时间 K +~v<F
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 k3 l
/** Creates a new instance of CountThread */ f[IchCwX
public CountControl() {} sD8S2
public synchronized void executeUpdate(){ guv@t&;t0
Connection conn=null; 0R&
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PreparedStatement ps=null; Z=0W@_s
try{ =FmU]DV
conn = DBUtils.getConnection(); x/=j$oA
conn.setAutoCommit(false); j;)6uia*A
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); qedGBl&
for(int i=0;i<CountCache.list.size();i++){ MbfzGYA2~
CountBean cb=(CountBean)CountCache.list.getFirst(); eEQ[^i
CountCache.list.removeFirst(); ?_aR-[XRg
ps.setInt(1, cb.getCountId()); NJ>p8P`_k
ps.executeUpdate();⑴ 0?SLRz8
//ps.addBatch();⑵ er0D5f R
} k`TJ<Dv;
//int [] counts = ps.executeBatch();⑶ 86#mmm)
conn.commit(); &._!)al
}catch(Exception e){ t\i1VXtO
e.printStackTrace(); (L$~zw5gr
} finally{ Nz*sD^SJa
try{ |Vi&f5p,@
if(ps!=null) { n#Roz5/U
ps.clearParameters(); (:QQ7xc{}
ps.close(); n*Vd<m;w
ps=null; +5[oY,^cO
} -kbm$~P
}catch(SQLException e){} }4SSo)Uv/
DBUtils.closeConnection(conn); Y/H^*1
} xXZKj
} pFTlhj)1
public long getLast(){ n=? 0g;1!
return lastExecuteTime; P]"deB|
} P/Kit?kngS
public void run(){ hFMst%:y$
long now = System.currentTimeMillis(); V:BX"$J1
if ((now - lastExecuteTime) > executeSep) { nud=uJ"(
//System.out.print("lastExecuteTime:"+lastExecuteTime); iIaT1i4t.
//System.out.print(" now:"+now+"\n"); 9T2A)a]0
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zpqGh
lastExecuteTime=now; )7GLS\uf<%
executeUpdate(); WEtA4zCO
} 8e!DDh
else{ hG7S]\N_
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); VONAw3k7!
} P0e ""9JOo
} TE%#$q
} ttaQlEa=Z
//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 Q)`gPX3F
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类写好了,下面是在JSP中如下调用。 H'{?aaK|t
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<% -I-Uh{)j
CountBean cb=new CountBean(); |90
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 1Xr"h:U_X
CountCache.add(cb); t-i6 FS-
out.print(CountCache.list.size()+"<br>"); H:-A; f!Z
CountControl c=new CountControl(); *fi;ZUPW3
c.run(); 8i;)|z7
out.print(CountCache.list.size()+"<br>"); yW^IN8fm
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