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: p*'?(o:=
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CountBean.java /[-hJ=<Yb
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/* @GV^B'}*
* CountData.java j?,$*Fi
* ls5S9R 5
* Created on 2007年1月1日, 下午4:44 R's xa*VB
* +l#2u#e
* To change this template, choose Tools | Options and locate the template under =os j}(
* the Source Creation and Management node. Right-click the template and choose 7D^A:f
* Open. You can then make changes to the template in the Source Editor.
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*/ g=%&p?1@E
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package com.tot.count; ~Mx
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/** nZ*P:K t:
* K$Ph$P@
* @author g,;MV7yE
*/ Uwp
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public class CountBean { y/FisX
private String countType; bODl
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int countId; BAhC-;B#R
/** Creates a new instance of CountData */ `4=b|N+b"
public CountBean() {} @K/Ia!Lw
public void setCountType(String countTypes){ S;NXOsSu
this.countType=countTypes; 2*|]#W
} =
` ^jz}
public void setCountId(int countIds){ LWI~m2
this.countId=countIds; L`#+ZLo
} "Wm~\)t(
public String getCountType(){ 2
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return countType; Yx"z&J9p
} ~g{,W
public int getCountId(){ qj1z>,\
return countId; w# e'K-=
} |(%H O@i
} d}ZHY[
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CountCache.java ^6+x0[13
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/* =Wf@'~K0k"
* CountCache.java ;i9CQ0e?
* "7HB3?2>W
* Created on 2007年1月1日, 下午5:01 1 XG-O
* |$PLZ,
* To change this template, choose Tools | Options and locate the template under $<v_Vm?6d
* the Source Creation and Management node. Right-click the template and choose v\ Ljm,+
* Open. You can then make changes to the template in the Source Editor. !A!\S/x4
*/ Ro<kp8
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package com.tot.count; ))`Zv=y"
import java.util.*; MxR U6+a
/** q3F5\6aN
* [Ni4[\
* @author H#inr^Xa
*/ 2?QJh2
public class CountCache { B$l`9!,
public static LinkedList list=new LinkedList(); 9$&e~^&B
/** Creates a new instance of CountCache */ &>e DCs
public CountCache() {} PoJ$%_a}
public static void add(CountBean cb){ QCR-l xO1
if(cb!=null){ BuTIJb+Q\
list.add(cb); 86#mmm)
} $)Yo g]}
} }&DB5M
} %v[Kk-d
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CountControl.java "Vq]|j,B/c
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/* +5[oY,^cO
* CountThread.java wkD:i 2E7
* pm]DxJ@
* Created on 2007年1月1日, 下午4:57 -vHr1I<
* "<x~{BN?
* To change this template, choose Tools | Options and locate the template under -j_I_
* the Source Creation and Management node. Right-click the template and choose 5lnSa+_/f
* Open. You can then make changes to the template in the Source Editor. SDHc[66'
*/ Wk\@n+Q{]
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package com.tot.count; U5!f++
import tot.db.DBUtils; `8;,&<U'`
import java.sql.*; ]TgP!M&q
/** TE%#$q
* ]"Y%M'
* @author uxyTu2L7
*/ GWhAjL/N
public class CountControl{ lVdT^"~3
private static long lastExecuteTime=0;//上次更新时间 W[E3P,XS
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 BD7@Mj*|
/** Creates a new instance of CountThread */ ^}Qj}
public CountControl() {} GrR0RwnH)?
public synchronized void executeUpdate(){ hNnX-^J<o
Connection conn=null; xDJ+BQ<1A
PreparedStatement ps=null; `%M-7n9Y
try{ `n`"g<K)Q
conn = DBUtils.getConnection(); 8A^jD(|
conn.setAutoCommit(false); 0sDwTb"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 6_<s=nTX
for(int i=0;i<CountCache.list.size();i++){ zLQ#GF
CountBean cb=(CountBean)CountCache.list.getFirst(); s
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CountCache.list.removeFirst(); HCG@#W<wc
ps.setInt(1, cb.getCountId()); kAN;S<jSE
ps.executeUpdate();⑴ <*"pra{3
//ps.addBatch();⑵ f{Fe+iPc
} LxlbD#<V
//int [] counts = ps.executeBatch();⑶ ?96-" l
conn.commit(); jD/7/G*
}catch(Exception e){ ("E!Jyc!
e.printStackTrace(); /^LH
} finally{ AB"1(PbG
try{ px|>v8
if(ps!=null) { ZP6x
ps.clearParameters(); a1G9wC:e
ps.close(); v0`qMBr1y
ps=null; tyuk{*Me:
} R6q4 ["
}catch(SQLException e){} *:9 >W$0u
DBUtils.closeConnection(conn); TTZ['HP
oI
} 2K]IlsMO&
} LgP> u?]n
public long getLast(){ |,;twj[?4
return lastExecuteTime; >wKu6-
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} 7k[pvd|L
public void run(){ uZ\wwYY#M
long now = System.currentTimeMillis(); |
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if ((now - lastExecuteTime) > executeSep) { j9URl$T:
//System.out.print("lastExecuteTime:"+lastExecuteTime); "($Lx
//System.out.print(" now:"+now+"\n"); V)0[`zJ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 4[TS4p
lastExecuteTime=now; &@YFje6Lcm
executeUpdate(); "H>r-cyh
} @sw9A93A
else{ 4D^ M<Xn
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); GS
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} -uA 3Y
} =Kc|C~g
} M*5,O
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 4l lD6&%
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类写好了,下面是在JSP中如下调用。 e9CP802#2
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<% qDnCn H
CountBean cb=new CountBean(); Hp btj
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); [D3+cDph
CountCache.add(cb); *8$>Whr
out.print(CountCache.list.size()+"<br>"); <nDNiM#
CountControl c=new CountControl(); {TyCj?3 B
c.run(); vv+TKO
out.print(CountCache.list.size()+"<br>"); K;oV"KRK
%>