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'oM%G[
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CountBean.java VJX{2$L
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/* gOI#$-L
* CountData.java *=1;HN3
* &t+
* Created on 2007年1月1日, 下午4:44 \guZc}V]:\
* .[hQ#3)W
* To change this template, choose Tools | Options and locate the template under %:n1S]Vr
* the Source Creation and Management node. Right-click the template and choose 6rEt!v #K[
* Open. You can then make changes to the template in the Source Editor. *Rv eR?kO
*/ n<p`OKIV3
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package com.tot.count; z^Nnt
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/** xQ62V11R6
* 8{HeHU
* @author L!3AiAnr
*/ W>Y8 u8
public class CountBean { SzR0Mu3uK
private String countType; [IVT0
i
int countId; w|x=^
/** Creates a new instance of CountData */ H(ht{.sjI
public CountBean() {} )EYsqj
public void setCountType(String countTypes){ (XJehdB0
this.countType=countTypes; I?v)>||Q
} 0Ng6Xg(QHc
public void setCountId(int countIds){ Bo?uwi
this.countId=countIds; .*>LD
} OE-$P
public String getCountType(){ X6~y+R
return countType; BJk:h-m [
} Jp.Sow
public int getCountId(){ />XfK,c-
return countId; Z&=K+P
} BBw`8!
} J.:"yK""
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CountCache.java /d5_-AB(v
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/* kwdmw_
* CountCache.java ^ 3LM%B
* h)q:nlKUW
* Created on 2007年1月1日, 下午5:01 PG9won5_
* $Trkow%F]
* To change this template, choose Tools | Options and locate the template under =1lKcA[z
* the Source Creation and Management node. Right-click the template and choose J={$q1@lq
* Open. You can then make changes to the template in the Source Editor. -9/YS
*/ 9U6y<X
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package com.tot.count; j4le../N
import java.util.*; Qp<?[C}'W
/** TH/!z,(>
* &-+qB
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* @author 4hztYOhJ{
*/ Hjli)*ev
public class CountCache { M|FwYF^
public static LinkedList list=new LinkedList(); +&tY&dQQB
/** Creates a new instance of CountCache */ K;G1cFFyG
public CountCache() {} RMDs~
public static void add(CountBean cb){ 71cc6T
if(cb!=null){ 1j6ZSE/*|
list.add(cb); <\?ySto
} Wt"@?#L
} n.67f
} ?)1h.K1}M
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CountControl.java [9a0J):w{
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/* Q<zL;AJ
* CountThread.java $} l0Nh'Eu
* !
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* Created on 2007年1月1日, 下午4:57 b,7:=-D
* jgYUS@}
* To change this template, choose Tools | Options and locate the template under p*W4^2(d
* the Source Creation and Management node. Right-click the template and choose 5JDqSz{
* Open. You can then make changes to the template in the Source Editor. {g l-tRC3
*/ ][ :6En}
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package com.tot.count; ]1%H.pF
import tot.db.DBUtils; }f^r@3Cb3
import java.sql.*; `8\pihww
/** QY-P!JD
* >Fz_]z
* @author NaG1j+LN
*/ ZP*Hx
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public class CountControl{ v*QobI
private static long lastExecuteTime=0;//上次更新时间 z]Z>+|
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1QE-[|
/** Creates a new instance of CountThread */ l},*^Sn<5
public CountControl() {} Q <^'v>~n
public synchronized void executeUpdate(){ d#I'9O0&
Connection conn=null;
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PreparedStatement ps=null; O?D*<rwD
try{ kJ>l,AD/
conn = DBUtils.getConnection(); X6!u(plVQ
conn.setAutoCommit(false); CBs0>M/
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); }k
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for(int i=0;i<CountCache.list.size();i++){ C>N)~Ut
CountBean cb=(CountBean)CountCache.list.getFirst(); 9fvy)kX;s
CountCache.list.removeFirst(); ;38DB o
ps.setInt(1, cb.getCountId()); h(] O;a-
ps.executeUpdate();⑴ nWbe=z&y8[
//ps.addBatch();⑵ ~m[^|w
} @pY AqX2
//int [] counts = ps.executeBatch();⑶ )#T(2A
conn.commit(); ]&yO>\MgJB
}catch(Exception e){ (E&}SI~
e.printStackTrace(); '\l(.N
} finally{ C#p$YQf
try{ N+b"LZc
if(ps!=null) { Ne@Iv)g?
ps.clearParameters(); gx4`pH;B\
ps.close(); =iRc&
ps=null; "X>Z!>
} nO$(\
z)
}catch(SQLException e){} iF{eGi
DBUtils.closeConnection(conn); 9/{+,RpC
} ai`fP{WlX
} .gv J;A7
public long getLast(){ JV/K ouL
return lastExecuteTime; 4cr
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} W4QVWn %3
public void run(){ P00d#6hPJ
long now = System.currentTimeMillis(); +J]3)8y+
if ((now - lastExecuteTime) > executeSep) { 7zVaj"N(
//System.out.print("lastExecuteTime:"+lastExecuteTime); 8 ]dhNA5
//System.out.print(" now:"+now+"\n"); p<`q^D
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,/m<= `*N|
lastExecuteTime=now; K;_p>bI5
executeUpdate(); |
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} \5k[ "8~
else{ JnmJN1@I
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); nC qUg_{D
} ,78QLh9:
} my[)/'
} +T
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//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 5X|=qZ
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类写好了,下面是在JSP中如下调用。 /o.wCy,J<
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<% HpSgGhL'J&
CountBean cb=new CountBean(); G!8O*4+A
cb.setCountId(Integer.parseInt(request.getParameter("cid")));
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CountCache.add(cb); WsL*P.J
out.print(CountCache.list.size()+"<br>"); d&wg\"E
CountControl c=new CountControl(); E6NkuBQ((
c.run(); "|]'\4UdzQ
out.print(CountCache.list.size()+"<br>"); 2!-ZNd:(+
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