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: IeF keE
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CountBean.java "DSPPE&[c
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/* Q;h3v1GC\P
* CountData.java F9XT
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* .~=HgOJ
* Created on 2007年1月1日, 下午4:44 Wv K(G3
* uD>z@J-v
* To change this template, choose Tools | Options and locate the template under -NM0LTF
* the Source Creation and Management node. Right-click the template and choose R9r+kj_
* Open. You can then make changes to the template in the Source Editor. ,
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*/ 6ri#Lw
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package com.tot.count; en9en=n|
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/** _MYx%Z
* 45}v^|Je\
* @author /N^~U&7
*/ 5)+F(
public class CountBean { $W!]fcZlB
private String countType; P#G.lft"O
int countId; FMu!z
/** Creates a new instance of CountData */ K5 vNhA
public CountBean() {} IG.f=+<0
public void setCountType(String countTypes){ E`p'L!z
this.countType=countTypes; #*%fu
} K&pM o.
public void setCountId(int countIds){ TGWdyIk
this.countId=countIds; +cfziQ$'
} %"7WXOv&z
public String getCountType(){ mf 4z?G@6
return countType; zS%
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} wz@FrRP=
public int getCountId(){ ^!>.97*
return countId; ;9rTE|n
} 2uu[52H8d%
} fykI,!
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CountCache.java I]sqi#h$2W
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/* \j:gr>4
* CountCache.java +G!v!(Ob+
* +rQg7a}
* Created on 2007年1月1日, 下午5:01 !d4HN.a7+u
* >Pkdu}xP3
* To change this template, choose Tools | Options and locate the template under <;KRj85"j
* the Source Creation and Management node. Right-click the template and choose di_gWE
* Open. You can then make changes to the template in the Source Editor. </w7W3F
*/ 92(~'5Qr
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package com.tot.count; -><QFJ
import java.util.*; T5{T[YdX<
/** 8dV=1O$/
* 1E^{B8cm
* @author =dn1}
*/ nh. b/\o
public class CountCache { z[FI2jl
public static LinkedList list=new LinkedList(); ;siJ~|6)
/** Creates a new instance of CountCache */ )v-Cj_W5]"
public CountCache() {} NV(fN-L
public static void add(CountBean cb){ T:@7S
if(cb!=null){ ~GYpat
list.add(cb); )T<D6l
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} s9:%s*$u
} u
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} <!hpfTz*
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CountControl.java CMKhS,,o
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/* +QQYPEx+
* CountThread.java 1[[TB .xF
* hC|KH}aCR)
* Created on 2007年1月1日, 下午4:57 IE@ z@+\(
* G#g{3}dcK
* To change this template, choose Tools | Options and locate the template under rkP4<E-M
* the Source Creation and Management node. Right-click the template and choose '@S,V/jy0z
* Open. You can then make changes to the template in the Source Editor. HD~jU>}}
*/ J,`_,T
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package com.tot.count; F42TKPN^uu
import tot.db.DBUtils; v?%0~!
import java.sql.*; Flne=ij6g
/** uJm #{[
* &:C{/QnA
* @author 3P3:F2S R
*/ `L+~&M
public class CountControl{ bA0uGLc
private static long lastExecuteTime=0;//上次更新时间 xan/ay>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 &,_?>.\[<
/** Creates a new instance of CountThread */ qU}lGf!dVn
public CountControl() {} hQP6@KIe)
public synchronized void executeUpdate(){ o9~h%&
Connection conn=null; `6n!$Cxo
PreparedStatement ps=null; qYDj*wqf
try{ PGMv(}%;
conn = DBUtils.getConnection(); % Mw' e/?
conn.setAutoCommit(false); T&mbXMN
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); e%'z=%(
for(int i=0;i<CountCache.list.size();i++){ vx PDC~3;
CountBean cb=(CountBean)CountCache.list.getFirst(); #?A]v>I;C
CountCache.list.removeFirst(); CF,8f$:2
ps.setInt(1, cb.getCountId()); /bu'6/!`
ps.executeUpdate();⑴ KuU3DTS85Z
//ps.addBatch();⑵ .wM:YX'[G
} !k%l+I3J[
//int [] counts = ps.executeBatch();⑶ Gmqs`{tc
conn.commit(); kf}F}Ad:%
}catch(Exception e){ A>J1B(up
e.printStackTrace(); Ny]'RS-
} finally{ @'@s*9Nr
try{ XTIu(f|d_;
if(ps!=null) { JgxE|#*7U
ps.clearParameters(); L,yA<yrC
ps.close(); 'E@2I9Kj
ps=null; @*bvMEE
} g"TPII$
}catch(SQLException e){} 8x!+tw7
DBUtils.closeConnection(conn); g&|4
} 0>I]=M]@
} QQ5lW
public long getLast(){ j{-mQTSD
return lastExecuteTime; **Qe`}E:
} wBg<Q{J
public void run(){ M-}j9,oR`
long now = System.currentTimeMillis(); 7W6eiUI'
if ((now - lastExecuteTime) > executeSep) { `4$4bXrP'
//System.out.print("lastExecuteTime:"+lastExecuteTime); MT;SRAmUr
//System.out.print(" now:"+now+"\n"); W\nHX I
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); *(@L+D0N
lastExecuteTime=now; E\
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executeUpdate(); N8Rm})
} =}B4I
else{ P@^z:RS*{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~uP
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} 2U=/<3;u
} ^#<:<X6
} g,A.Y,})
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 [K"U_b}w
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类写好了,下面是在JSP中如下调用。 ?/o2#iJx
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<% ws*~$x?7
CountBean cb=new CountBean(); L?Kz
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); xn%l
CountCache.add(cb); Qx6,>'Qk'
out.print(CountCache.list.size()+"<br>"); /}h71V!
CountControl c=new CountControl(); GI 0x>Z+
c.run(); oG4w8+N
out.print(CountCache.list.size()+"<br>"); S3j]{pZ(z
%>