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: j]'ybpMT"
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CountBean.java yn|U<Hxl~H
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/*
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* CountData.java wo5fGQJ
* *('Vyd!n
* Created on 2007年1月1日, 下午4:44 P2g}G4qf
* SQ-CdpT<
* To change this template, choose Tools | Options and locate the template under :0'vz M
* the Source Creation and Management node. Right-click the template and choose #tN!^LLi
* Open. You can then make changes to the template in the Source Editor. a St:G*a"
*/ %*];XpAE
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package com.tot.count; g_;4@jwTP"
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/** #b>D^=NV>)
* p-kug]qX
* @author B3Da w/G
*/ F*p@hl
public class CountBean { mWTV)z57
private String countType; dmPAPCm%y
int countId; 1otE:bi
/** Creates a new instance of CountData */ UId?a}J
public CountBean() {}
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public void setCountType(String countTypes){ f0 "_ {\
this.countType=countTypes; K;*B$2Z#k
}
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public void setCountId(int countIds){ KJi8LM
this.countId=countIds; \[L|
} wxE'h~+
public String getCountType(){ ( 9(NP_s
return countType;
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} $fAZ^
public int getCountId(){ ?X@uR5?{
return countId; @dc4v_9
} \[<8AV"E-'
} n'83P%x
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CountCache.java GP0}I@>?
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/* 0?*":o30
* CountCache.java C&f{LpB`
* G2w0r,[
* Created on 2007年1月1日, 下午5:01 Zp+orc7
* Cuc+9
* To change this template, choose Tools | Options and locate the template under }BAe
* the Source Creation and Management node. Right-click the template and choose C4K"eX,K
* Open. You can then make changes to the template in the Source Editor. VJS1{n=;k
*/ "0m\y+%8
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package com.tot.count; #:8V<rc^
import java.util.*; o3Z<tI8-V
/** :czUOZ_
* Zb:S
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* @author ]%Lk#BA@A
*/ KqvM5$3
public class CountCache { ld7B{ ?]
public static LinkedList list=new LinkedList(); kiu#THF
/** Creates a new instance of CountCache */ ^zKP5nzL
public CountCache() {} H=6-@+ !o
public static void add(CountBean cb){ jH[{V[<#X
if(cb!=null){ VEx
)
list.add(cb); m%U$37A1
} y4,t=Gq7^
} =U}!+ 8f
} zU";\);
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CountControl.java TNlS2b1
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/* q3ebps9^
* CountThread.java wDKA1i%G
* h3V;
J
* Created on 2007年1月1日, 下午4:57 R<Ct{f!
*
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* To change this template, choose Tools | Options and locate the template under emG1Wyl
* the Source Creation and Management node. Right-click the template and choose 9>ML;$T&
* Open. You can then make changes to the template in the Source Editor. P.3kcZ
*/ P(B&*1X
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package com.tot.count; u_.Ig|Va
import tot.db.DBUtils; VKu|=m2vB
import java.sql.*; USV;j%U4*
/** e7n`fEpO
* bdj')%@n
* @author * & : J
*/ 3^]Kd
public class CountControl{ smPZ%P}P+c
private static long lastExecuteTime=0;//上次更新时间 +oiuulA
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 U/jCM?~
/** Creates a new instance of CountThread */ y-_IMu.J`
public CountControl() {} ; Z2
public synchronized void executeUpdate(){ K}QZdN']
Connection conn=null; @gi / 1 cq
PreparedStatement ps=null; E+P-)bRa
try{ QLb!e"C
conn = DBUtils.getConnection(); 95*=&d
conn.setAutoCommit(false); 7upN:7D-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); |M|>/U 8
for(int i=0;i<CountCache.list.size();i++){ bf/z
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CountBean cb=(CountBean)CountCache.list.getFirst(); UxvT|~"
CountCache.list.removeFirst(); "cGjHy\j`
ps.setInt(1, cb.getCountId()); m]&y&oz
ps.executeUpdate();⑴ u XVs<im
//ps.addBatch();⑵ v dPb-z4
} 4K$_d,4`U
//int [] counts = ps.executeBatch();⑶ R2y~+tko?
conn.commit(); s\.\z[1
}catch(Exception e){ F+9(*|x%
e.printStackTrace(); j5m]zh5\J=
} finally{ ye`-U?7.
try{ 4#ZZwa]y
if(ps!=null) { /e7BW0$1
ps.clearParameters(); 6f&qtJQ<A
ps.close();
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ps=null; |t_SN,)dd
} Q\aC:68
}catch(SQLException e){} ),I g u
DBUtils.closeConnection(conn); q}hHoSG]=
} JxlZ,FF$@
} lz(}N7SLa
public long getLast(){ zZiga q"
return lastExecuteTime; ,j%feC3
} tw&biLM5T
public void run(){ :)kWQQ+,
long now = System.currentTimeMillis(); LuWY}ste
if ((now - lastExecuteTime) > executeSep) { t{O2JF#5u
//System.out.print("lastExecuteTime:"+lastExecuteTime); J"Nn.iVq
//System.out.print(" now:"+now+"\n"); #4F0o@Z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !gj_9"<
lastExecuteTime=now; $`_xP1bUT
executeUpdate(); d>Ky(wS
} +[Q`I*C
else{ GhW{6.^
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); K&up1nZ@(
} h%! ,|[|
} -Hg,:re2
} gCM(h[7A
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 m,r>E%;Cj
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类写好了,下面是在JSP中如下调用。 xn}HB
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<% J:0`*7
CountBean cb=new CountBean(); U8 n=Ro
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Ns.{$'ll
CountCache.add(cb); rXVRX#Lh
out.print(CountCache.list.size()+"<br>"); -!X\xA/KN
CountControl c=new CountControl(); Ee'wsL
c.run(); %[fZ@!B
out.print(CountCache.list.size()+"<br>"); ?A~a}bFZ
%>