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: [}ayaXXQ5
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CountBean.java Mn>/\e
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/* O-uno{Fd*
* CountData.java (g HCu
* ^osXM`
* Created on 2007年1月1日, 下午4:44 $:l>g)c
* A.YXK%A%
* To change this template, choose Tools | Options and locate the template under E&z`BPd
* the Source Creation and Management node. Right-click the template and choose Vf*Z }'
* Open. You can then make changes to the template in the Source Editor. or<n[<D-C
*/ iY[+BI:
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package com.tot.count; Bz+zEXBC
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/** U\'HB.P\
*
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* @author nY)H-u^
*/ 7$zeRYD+
public class CountBean { #Ch*a.tI@
private String countType; '((pW
int countId; -xVp}RLT
/** Creates a new instance of CountData */ /}kG$~
public CountBean() {} qdCcMcGt
public void setCountType(String countTypes){ y3+iADo.p
this.countType=countTypes; L^E#"f
} QKB*N)%6
public void setCountId(int countIds){ cfZ$V^xM
this.countId=countIds; m8ApiGG
} ATG;*nIP
public String getCountType(){ E3vYVuw
return countType; {9
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} 3xX^pjk
public int getCountId(){ :5W8S6[o
return countId; `m")v0n3
} /$=<"Y7&g
} Tb!Fv W
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CountCache.java <
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/* 0d|DIT#>?
* CountCache.java =F<bAZ
* 7TU(~]Z
* Created on 2007年1月1日, 下午5:01 S*3*Q l*
* YQ-!>3/)-
* To change this template, choose Tools | Options and locate the template under )W,.xP
* the Source Creation and Management node. Right-click the template and choose [:BD9V
* Open. You can then make changes to the template in the Source Editor. \8<ZPqt9
*/ H_nIlku
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package com.tot.count; UKpc3Jo:~
import java.util.*; .+d.~jHX
/** 'c/S$_r
* k}&7!G@T
* @author 4 \Ig<C9
*/ q]2t3aY%
public class CountCache { S HxD(6
public static LinkedList list=new LinkedList(); 1DRih>+#
/** Creates a new instance of CountCache */ kMx^L;:n
public CountCache() {} @>Bgld&vl
public static void add(CountBean cb){
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if(cb!=null){ [,0[\NC
list.add(cb); Kl/n>qEt
} UbDpSfub
} oAprM Z7Y
} MHqk-4Mz
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CountControl.java q|zips,
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/* `UD,ne
* CountThread.java $n=w
* Y/<`C
* Created on 2007年1月1日, 下午4:57 (Go1@;5I
* 3j7Na#<tL3
* To change this template, choose Tools | Options and locate the template under @#QaaR;4
* the Source Creation and Management node. Right-click the template and choose `e[>S
* Open. You can then make changes to the template in the Source Editor. <Toy8-kj
*/ OB4nE}NO
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package com.tot.count; wTe 9OFv
import tot.db.DBUtils; A4{p(MS5
import java.sql.*; 91\Sb:>
/** oJ.5! Kg
* +mRc8 G
* @author Zg&o][T
*/ 6Z#$(oC
public class CountControl{ G0Y]-*1
private static long lastExecuteTime=0;//上次更新时间 f\vMdY
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 b*)F7{/Z
/** Creates a new instance of CountThread */ 3EV?=R
public CountControl() {} >&YUV.mLY
public synchronized void executeUpdate(){ %?X6TAtH
Connection conn=null; mW=9WV
PreparedStatement ps=null; eh;L])~C
try{ 85:KlBe%+
conn = DBUtils.getConnection(); +5x{|!Pn
conn.setAutoCommit(false); z'01V8e
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Y !%2vOt
for(int i=0;i<CountCache.list.size();i++){ :|%1i>O
CountBean cb=(CountBean)CountCache.list.getFirst(); GS&I6
CountCache.list.removeFirst(); -2B3 xIZJ
ps.setInt(1, cb.getCountId()); QV[#^1
ps.executeUpdate();⑴ 25Uw\rKeO
//ps.addBatch();⑵ ER,!`C]
} Vji:,k=3\
//int [] counts = ps.executeBatch();⑶ |)*9BN
conn.commit(); {,B.OM)J
}catch(Exception e){ e<$s~ UXv
e.printStackTrace(); ^{Fo,7
} finally{ }2hU7YWt
try{ NjbIt=y
if(ps!=null) { 2jF}n*[OW
ps.clearParameters(); *.
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ps.close(); <Rfx`mn
ps=null; 4MrUo9L$s
} |Ae7wXOs
}catch(SQLException e){} * hmoi
DBUtils.closeConnection(conn); *]:J@KGf
} ;(@' +"
} az[# q
public long getLast(){ oU|_(p"e|
return lastExecuteTime; c'DNO~H
} H X{K5 +
public void run(){ N
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long now = System.currentTimeMillis(); ?vP6~$*B
if ((now - lastExecuteTime) > executeSep) { a+^,EY
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9@8'*a{`m
//System.out.print(" now:"+now+"\n"); z|8zNt Ug
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); VG_xNM
lastExecuteTime=now; }5AA}=
executeUpdate(); []G@l. ]W
} Q7]bUPDO
else{ GuC 9h^[=M
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); M5:j)oW
} ~ycWcZi>
} 2f6BZ8H+Z
} BvS!P8
//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 qr (t_qR&
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类写好了,下面是在JSP中如下调用。 @JPz|
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<% 7+;.Q
CountBean cb=new CountBean(); M8R/a[ -A
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "R\D:Olb#
CountCache.add(cb); 8g {;o7
out.print(CountCache.list.size()+"<br>"); 'p[*2J"K4
CountControl c=new CountControl(); <v!jS=T
c.run(); 7LB%7~{<
out.print(CountCache.list.size()+"<br>"); @KRia{
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