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: a8r+G]Z
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CountBean.java f`_6X~
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/* >s"kL^
* CountData.java ? p^ ':@=
* r;OE6}L>
* Created on 2007年1月1日, 下午4:44 T
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* w}Xy;0c
* To change this template, choose Tools | Options and locate the template under vKNxL^x
* the Source Creation and Management node. Right-click the template and choose _CXXgF[OCA
* Open. You can then make changes to the template in the Source Editor. Rj{D#5
*/ >)S'`e4Gu
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package com.tot.count; wvg>SfV,e
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/** o$bD?Zn
* R3} Z"
* @author ' $X}' u
*/ %dA7`7j
public class CountBean { b:(*C
private String countType; qVmG"et'J
int countId; [:C!g#o
/** Creates a new instance of CountData */ kR|(hA,$N
public CountBean() {} Q5qQ%cu
public void setCountType(String countTypes){ 'C|yUsBC
this.countType=countTypes; ~yuj;9m3
} e+>&?
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public void setCountId(int countIds){ `(?x@Y>.Ht
this.countId=countIds; t"Djh^=y
} .6#Y-iJqc
public String getCountType(){ pM'AhzS
return countType; /-jk_8@a
} z hFk84
public int getCountId(){ \m;"KyP+
return countId; B|+tK
} NX4}o&mDwn
} 6sp?'GO`~
"Crm\UI6
CountCache.java [XP3
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/* 3Q"4-pd
* CountCache.java 0q
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* ,l_n:H+"F
* Created on 2007年1月1日, 下午5:01 ^atBf![
* O%(k$fvM
* To change this template, choose Tools | Options and locate the template under ="*8ja-K
* the Source Creation and Management node. Right-click the template and choose y*5bF0
* Open. You can then make changes to the template in the Source Editor. |k^ *
*/ U4@W{P02
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package com.tot.count; Qv@Z#
import java.util.*; s8<)lO<SV.
/** i%)Nn^a;T
* "?Cx4<nsM
* @author o-jF?9m
*/ ^.9I[Umua
public class CountCache { `?ijKZ}y5
public static LinkedList list=new LinkedList(); gnp\z/'>
/** Creates a new instance of CountCache */ Mo2b"A;}|
public CountCache() {} /)` kYD6
public static void add(CountBean cb){ *OQr:e<}
if(cb!=null){ &zYo
list.add(cb); g.d%z
} -a[]#v9
} NN9`jP2
} 058+_xX
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CountControl.java *XK9-%3
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/* 1wa zJj=v
* CountThread.java &&;ol}W
* LA.xLU3
* Created on 2007年1月1日, 下午4:57 u9*}@{,
* TKsze]/q
* To change this template, choose Tools | Options and locate the template under oiq7I@Y`x
* the Source Creation and Management node. Right-click the template and choose qi\!<clv
* Open. You can then make changes to the template in the Source Editor. U8z$=Wo
*/ x^|J-
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package com.tot.count; heliL/
import tot.db.DBUtils; GP5Y5)
import java.sql.*; <<da TQV
/** @]#0jiS
* JxP=[>I
* @author ,f4mFL0~N
*/ ?5qo>W<7
public class CountControl{ uLsGb=m%b
private static long lastExecuteTime=0;//上次更新时间 -T4{PM
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AT:T%a:G?
/** Creates a new instance of CountThread */ DG x9 \8^
public CountControl() {} Ok+zUA[Wu
public synchronized void executeUpdate(){ BHE((3
Connection conn=null; ai(<"|(
PreparedStatement ps=null; {g2cm'hD
try{ XB)e;R
conn = DBUtils.getConnection(); ,*2%6t`N?
conn.setAutoCommit(false); s7CoUd2
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); nBd!296
for(int i=0;i<CountCache.list.size();i++){ 9lA@ K[
CountBean cb=(CountBean)CountCache.list.getFirst(); 6rEt!v #K[
CountCache.list.removeFirst(); pCz;km
ps.setInt(1, cb.getCountId()); |i"A!rW
ps.executeUpdate();⑴ .#uRJo%8
//ps.addBatch();⑵ ~ySmN}3~'
} I72UkmK`
//int [] counts = ps.executeBatch();⑶ #dDsI]E)
conn.commit(); w0Fi~:b
}catch(Exception e){ 6u3DxFiTm
e.printStackTrace(); ,@=qaU
} finally{ H(ht{.sjI
try{ w~EXO;L2
if(ps!=null) { "aN<3b
ps.clearParameters(); zYdSg<[^
ps.close(); O`O{n_o^u
ps=null; ch<Fi%)
} 0K'lr;
}catch(SQLException e){} :4h4vp<
DBUtils.closeConnection(conn); ?#xNz=V
} PNXZ 3:W
}
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public long getLast(){ y6'Fi(2yw
return lastExecuteTime; EH"iK2n\9
} =YBwO. !%
public void run(){ $=$I^hV
long now = System.currentTimeMillis(); %*<k5#Yq
if ((now - lastExecuteTime) > executeSep) { g/so3F%v
.
//System.out.print("lastExecuteTime:"+lastExecuteTime); j3VM!/
//System.out.print(" now:"+now+"\n"); 6rL'hB!!]*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); $nQ; ++
lastExecuteTime=now; )_b#c+
executeUpdate(); MQ2gzKw>
} }1w[G;$
else{ ~)D2U:"^xm
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); kf0zL3|
} ]y$D@/L@
} BD,JBu]
} &Z5$
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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 =2bW"gs
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类写好了,下面是在JSP中如下调用。 ~R/7J{Sg
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<% |!dyk<}oIu
CountBean cb=new CountBean(); 8iD_md_[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Q<zL;AJ
CountCache.add(cb); ExI?UGT
out.print(CountCache.list.size()+"<br>"); h|dVVCsN
CountControl c=new CountControl(); GY<Y,
c.run(); Gp$[u4-6M6
out.print(CountCache.list.size()+"<br>"); e>1^i;f
%>