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: yZ U6xY
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CountBean.java ShP^A"Do
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/* Gk&)08
* CountData.java yEoF4bt
* LxSpctiNx
* Created on 2007年1月1日, 下午4:44 x,pjpx
* 0#Y5_i|p
* To change this template, choose Tools | Options and locate the template under 3J|F?M"N7
* the Source Creation and Management node. Right-click the template and choose `MN4uC
* Open. You can then make changes to the template in the Source Editor. ,~@X{7U
*/ $AjHbU.I{
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package com.tot.count; .glA
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/** VSI9U3t3w
* Ma']?Rb`
* @author g63(E,;;J
*/ a;qryUyG
public class CountBean { +RM SA^
private String countType; jTtu0Q|
int countId; }"P|`"WW
/** Creates a new instance of CountData */ CMG&7(MR
public CountBean() {} G+"t/?/
public void setCountType(String countTypes){ L;NvcUFn
this.countType=countTypes; U175{N%3
} :W.(S6O(
public void setCountId(int countIds){ {
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this.countId=countIds; bL+_j}{:N
} }1c|gQ
public String getCountType(){ /hH
return countType; Kp~VS<3
} Q4!_>YZ
public int getCountId(){ z2_*%S@
return countId; *ebSq)
} WwBOM~/`2
} Xq]w<$
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CountCache.java vrhT<+q
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/* +\c5]`
* CountCache.java DJXmGt]
* T@:Wp4>69
* Created on 2007年1月1日, 下午5:01 0w\zLU
* :Ij{s
* To change this template, choose Tools | Options and locate the template under GmeQ`;9,
* the Source Creation and Management node. Right-click the template and choose 5T_n %vz
* Open. You can then make changes to the template in the Source Editor. qo90t{|c
*/ :0j?oY~e
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package com.tot.count; <EB+1GFuI
import java.util.*; -aPg#ub
/** (cAIvgI
* _"Dv
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* @author j^j1
*/ /og=IF2:
public class CountCache { H1pO!>M
public static LinkedList list=new LinkedList(); c z#rb*b
/** Creates a new instance of CountCache */ 7 S#J>*
public CountCache() {} (>UZ<2GPL
public static void add(CountBean cb){ E"\<s3
if(cb!=null){ g|DF[
list.add(cb); 8`q:Gz=M\
} uB]7G0g:
} b,l$1{
} -[4T
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CountControl.java IXMop7~
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/* Gv!2f
* CountThread.java w=0(<s2
* iW]j9} t
* Created on 2007年1月1日, 下午4:57 iTBx\u%{
* U8s2|G;K
* To change this template, choose Tools | Options and locate the template under ]}<}lI9
* the Source Creation and Management node. Right-click the template and choose ="1Ind@w!
* Open. You can then make changes to the template in the Source Editor. L:KF_W.I+
*/ |B?m,U$A!
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package com.tot.count; :[p}
import tot.db.DBUtils; y|C(X
import java.sql.*; y2Q&s9$Do
/** .KB^3pOpx
* Gvt G(u~
* @author @wGPqg
*/ dc+>m,3$
public class CountControl{ rT=rrvV3g
private static long lastExecuteTime=0;//上次更新时间 )!th7sH
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 vONasD9At
/** Creates a new instance of CountThread */ [SjqOTon{
public CountControl() {} 8l>?Pv
public synchronized void executeUpdate(){ J|W<;
Connection conn=null; }kw#7m54
PreparedStatement ps=null; 9@SC}AF.
try{ :(E@Gf
conn = DBUtils.getConnection(); sNbxI|B
conn.setAutoCommit(false); a(m2n.0'>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 5c@,bIl *
for(int i=0;i<CountCache.list.size();i++){ h/QXPdV
CountBean cb=(CountBean)CountCache.list.getFirst(); ^rB8? kt
CountCache.list.removeFirst(); -mbt4w
ps.setInt(1, cb.getCountId()); iQ0KfoG?U
ps.executeUpdate();⑴ SpIv#?
//ps.addBatch();⑵ Fx] WCQo
} :tc@2/>!O
//int [] counts = ps.executeBatch();⑶ [7:,?$tC
conn.commit(); juP7P[d$qW
}catch(Exception e){ i7CX65&b
e.printStackTrace(); 7zl5yKN
} finally{ ,5P0S0*{
try{ #z'
if(ps!=null) { ` _6C{<O
ps.clearParameters(); =bAx,,D#
ps.close(); 3xy<tqfr
ps=null; DcS+_>a\{l
} h7*J9[$
}catch(SQLException e){} Ky`qskvu
DBUtils.closeConnection(conn); `{gHA+B
} 8:q1~`?5"b
} K$z2YJ%
public long getLast(){ Qry@
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return lastExecuteTime; b3P+H r
} +Z,;,5'5G
public void run(){ [XN={
long now = System.currentTimeMillis(); -D<< kra
if ((now - lastExecuteTime) > executeSep) { mupT<_Y
//System.out.print("lastExecuteTime:"+lastExecuteTime); d.aS{;pse
//System.out.print(" now:"+now+"\n"); Q1lyj7c#x
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); W
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lastExecuteTime=now; ,S\CC{!
executeUpdate(); \a<wKTkn
} {aZ0;
else{ [=C6U_vU
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); D=TvYe
} \-E^lIVF
} -$\y_?}
} OUE(I3_
//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|5Okq g
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类写好了,下面是在JSP中如下调用。 $Ph|e)p
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<% cF*TotU_m
CountBean cb=new CountBean(); v{RZJ^1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); b\f
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CountCache.add(cb); IZf{nQ[0
out.print(CountCache.list.size()+"<br>"); EZgwF=lO
CountControl c=new CountControl(); cs48*+m
c.run(); 39c2pV[
out.print(CountCache.list.size()+"<br>"); 8H[<X_/ke
%>