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: 8_m9CQ6 i
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CountBean.java \k=Qq(=
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/* {|h"/
* CountData.java Qzhnob#C9
* -X[[
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* Created on 2007年1月1日, 下午4:44 \?^wu
* @qDrTH]5
* To change this template, choose Tools | Options and locate the template under 4sQAR6_SW~
* the Source Creation and Management node. Right-click the template and choose {?y7'
* Open. You can then make changes to the template in the Source Editor. +E~`H^
*/ Z
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package com.tot.count; weV#%6=5\
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/** zrO|L|F&P
* fti|3c
* @author 1^#Q/J,
*/ t"p#iia
public class CountBean { *`-29eR"8
private String countType; zjS:;!8em
int countId; F\R}no5C
/** Creates a new instance of CountData */ cOZ^huK
public CountBean() {} y7-:l u$9
public void setCountType(String countTypes){ J\ +gd%
this.countType=countTypes; b6Hk20+B;
} <M?#3&5A
public void setCountId(int countIds){ ;cn.s,
this.countId=countIds; GKhwn&qCKb
} ^6oqq[$
public String getCountType(){ s~ZFVi-i
return countType; !#I/be]
} &n.uNe
public int getCountId(){ @!/fvP
return countId; 25n(&NV
} /VO@>Hoh
} _0q~s@-
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CountCache.java FTnQqDuT
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/* ]C6[`WF
* CountCache.java idS
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* h;p%EZ
* Created on 2007年1月1日, 下午5:01 |K;Txe_
* 9*+0j2uhQ
* To change this template, choose Tools | Options and locate the template under llfiNEK5;
* the Source Creation and Management node. Right-click the template and choose RhNaYO
* Open. You can then make changes to the template in the Source Editor. +4g%?5'
*/ 51opP8
/)?P>!#;\
package com.tot.count; K_|~3g
import java.util.*; v6-~fcX0G
/** 'xZPIj+
* K}<!{/fi)
* @author %)Uvf`Xhh4
*/ h_chZB'
public class CountCache { E
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public static LinkedList list=new LinkedList(); -f2`qltjb
/** Creates a new instance of CountCache */ 0#fG4D_
public CountCache() {} UX'NJ1f
public static void add(CountBean cb){ u%1k
if(cb!=null){ 8C,utjy
list.add(cb); if[o?6U4t
} 4_762Gu%
} N3yB1_
} 1|WpKaMoq
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CountControl.java sMS9!{A
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/* ;#yu"6{
* CountThread.java QS [B
* ?hJsN
* Created on 2007年1月1日, 下午4:57 bjPbl2K
* -V
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* To change this template, choose Tools | Options and locate the template under vMX6Bg8
* the Source Creation and Management node. Right-click the template and choose dHq )vs,L
* Open. You can then make changes to the template in the Source Editor. ow+Dd[i
*/ EdAR<VfleA
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package com.tot.count; k g,ys4
import tot.db.DBUtils; hHc^ZA
import java.sql.*; (OyY_`
/** f >)Tq'
* k=mT!
* @author uH&,%k9GVK
*/ ('**nP
public class CountControl{ !P~ PF:W~|
private static long lastExecuteTime=0;//上次更新时间 h lkvk]v
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 (}FW])y
/** Creates a new instance of CountThread */ V4eng "
public CountControl() {} ~0F9x9V
public synchronized void executeUpdate(){ :#\B {)(
Connection conn=null; (' Ko#3b
PreparedStatement ps=null; `$V[;ld(mz
try{ Oh/b?|imG
conn = DBUtils.getConnection(); :q>oD-b$}
conn.setAutoCommit(false); ik Y]8BCc
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); xZP >g
for(int i=0;i<CountCache.list.size();i++){ bwSRJFqb
CountBean cb=(CountBean)CountCache.list.getFirst(); Z;fm;X%4
CountCache.list.removeFirst(); 0Z
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ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ c{,y{2c]LT
//ps.addBatch();⑵ =X`]Ct8Z
} /NW>;J}C
//int [] counts = ps.executeBatch();⑶ Im?= e
conn.commit(); tt7PEEf
}catch(Exception e){ !u53 3
e.printStackTrace(); {\svV
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} finally{ ,qe]fo >
try{ 5BU%%fBJ.
if(ps!=null) { vLBee>$
ps.clearParameters(); \,l.p_<
ps.close(); 8|5Gv
ps=null;
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} yE.495
}catch(SQLException e){} )l#%.Z9
DBUtils.closeConnection(conn); :Hzz{'
} w>6"Sc7oc2
} `J>E9p<
public long getLast(){ '&-5CpDUs
return lastExecuteTime; #QTfT&m+G}
} AaVI%$
public void run(){ jr,&=C(
long now = System.currentTimeMillis(); DJViy
if ((now - lastExecuteTime) > executeSep) { "ep `
//System.out.print("lastExecuteTime:"+lastExecuteTime); ASKAgU"h
//System.out.print(" now:"+now+"\n"); X,WQ'|rC
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); <JL\?)}n
lastExecuteTime=now; s-,=e
executeUpdate(); `Di ^6UK(
} fiE>H~
else{ G2CZwm{/f
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ka5#<J7<p
} }uF[Ra
} ?W[J[cb
} Qp kKVLi
//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 R`@8.]cpPy
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类写好了,下面是在JSP中如下调用。 i?GfY
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<% DKy>]Hca
CountBean cb=new CountBean(); SY%A"bC
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); cBz!U8(
CountCache.add(cb); ZnvEv;P
out.print(CountCache.list.size()+"<br>"); V!T^wh;
CountControl c=new CountControl(); wr$cK'5ZL
c.run(); k^H0b\hYY
out.print(CountCache.list.size()+"<br>"); ydwK!j0y
%>