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: 23'<R i
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CountBean.java qq?o^_^4
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/* ^e$!19g
* CountData.java z7P~SM
* Qk|+Gj
* Created on 2007年1月1日, 下午4:44 J5<16}*
* i;Kax4k
* To change this template, choose Tools | Options and locate the template under '9Q#%E!*
* the Source Creation and Management node. Right-click the template and choose rmWsob
* Open. You can then make changes to the template in the Source Editor. oS Ybx:2wo
*/ JIYzk]Tj
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package com.tot.count; 'X4)2iFV
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/** xBf->o S?
* g2M1zRm;
* @author zqQ[uO]m?
*/ ^;[_CF_
public class CountBean { Gfy9YH~
private String countType; CeUXGa|C
int countId; P)Oe?z;G?
/** Creates a new instance of CountData */ B"5xs
public CountBean() {} 1#fR=*ZM"
public void setCountType(String countTypes){ X1[zkb
this.countType=countTypes; 3Tw9Uc\vT
} cT&lkS
public void setCountId(int countIds){ 'V <ZmJ2
this.countId=countIds; Be^"sC
} B*tQ0`
public String getCountType(){ n\BV*AH
return countType; */@I$*
} @~5Fcfmm
public int getCountId(){ _^ n>kLd$
return countId; MJH>rsTQ
} ^Q+z^zlC
} 0G Q8}r
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CountCache.java X(8LhsP
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/* nYvkeT
* CountCache.java Lm1JiPs d
* _)YB*z5
* Created on 2007年1月1日, 下午5:01 U 17=/E
* &%(SkL_]
* To change this template, choose Tools | Options and locate the template under *%atE
* the Source Creation and Management node. Right-click the template and choose $
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* Open. You can then make changes to the template in the Source Editor. SD@ 0X[
*/ 7*WO9R/
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package com.tot.count; b+f
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import java.util.*; q& KNK
/** 1>2
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* O CCC' k
* @author ^'+#BPo9@
*/ vD/l`Ib:
public class CountCache { 1g$xKe~]4
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ I1K %n'D
public CountCache() {} ^R(=4%8%"
public static void add(CountBean cb){ wM-H5\9n
if(cb!=null){ ?zVE7;r4U
list.add(cb); J'WOqAnPZ
} 1r*@1y<0"
} #i.BOQxS
} gt~u/Z%
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CountControl.java LFYSur8
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/* \~U:k4
* CountThread.java e~R_ bBQ0
* a6It1%a+
* Created on 2007年1月1日, 下午4:57 YZ<5-C
* k!WeE#"(
* To change this template, choose Tools | Options and locate the template under VrhHcvnZ
* the Source Creation and Management node. Right-click the template and choose (VHPcoL
* Open. You can then make changes to the template in the Source Editor. WVp6/HS
*/ ]zIIi%
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package com.tot.count; .>-D{
import tot.db.DBUtils; 2Ib
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import java.sql.*; R -mn8N&
/** ^i3!1cS
* iVmy|ewd
* @author 8R(l~
*/ hwi_=-SL
public class CountControl{ pm[i#V<v
private static long lastExecuteTime=0;//上次更新时间 Aq>?G+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 /h]ru SI
/** Creates a new instance of CountThread */ C?<-`$0
public CountControl() {} y Tk1
public synchronized void executeUpdate(){ z 61F q
Connection conn=null; REsw=P!b
PreparedStatement ps=null; I'2I'x\M
try{ 8"V1h72vcW
conn = DBUtils.getConnection(); %`/F>`
conn.setAutoCommit(false); z XU r34jF
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); fy&u[Jd{
for(int i=0;i<CountCache.list.size();i++){ #nZPnc:
CountBean cb=(CountBean)CountCache.list.getFirst(); M}=>~TA@
CountCache.list.removeFirst(); !g#y$
ps.setInt(1, cb.getCountId()); A2P.5EN
ps.executeUpdate();⑴ 1jPh0?BY
//ps.addBatch();⑵ l=$?#^^ /
} 5rQu^6&
//int [] counts = ps.executeBatch();⑶ KAu>U3\/
conn.commit(); uy<b5.!-
}catch(Exception e){ G2P:|R
e.printStackTrace(); +u&3pK>f
} finally{ t/3qD7L
try{ $}us+hGZ
if(ps!=null) { -<" ;|v4
ps.clearParameters(); {/48n83n
ps.close(); #|=lU4Bf
ps=null; g{2~G6%;0
} G6JP3dOT
}catch(SQLException e){} ~HKzqGQy>
DBUtils.closeConnection(conn); :wUi&xw
} 8 ~Pdr]5
} 2{oQ
public long getLast(){ oMoco tQ;$
return lastExecuteTime; l2Rnyb<;;
} it-2]Nw
public void run(){ j|XL$Q
long now = System.currentTimeMillis(); -q?,
if ((now - lastExecuteTime) > executeSep) { ]4K4Nh~
//System.out.print("lastExecuteTime:"+lastExecuteTime); VAqZ`y
//System.out.print(" now:"+now+"\n"); .}(X19R
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 3hA5"G+7
lastExecuteTime=now; 95ix~cH3q
executeUpdate(); TWfkr
} .%M80X{5~
else{ <l eE.hhf.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ;Qc^xIPy
} _E/
} "2 :zWh7|
} @V^5_K
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 2a 7"~z~
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类写好了,下面是在JSP中如下调用。 ;r.#|b
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<% "/3YV%to-#
CountBean cb=new CountBean(); qT#NS&T!-
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); MfdkvJ'
CountCache.add(cb); 8cURYg6v
out.print(CountCache.list.size()+"<br>"); ]A1'+!1$
CountControl c=new CountControl(); ~I~lb/
c.run(); F9A5}/\
out.print(CountCache.list.size()+"<br>"); =&DuQvN,
%>