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: 6X \g7bg
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CountBean.java gQn%RPMh
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/* c7e,lgG-
* CountData.java AFrJzh:V[
* 80=0S^gEZ
* Created on 2007年1月1日, 下午4:44
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* 1MN!
* To change this template, choose Tools | Options and locate the template under C96/
* the Source Creation and Management node. Right-click the template and choose P%3pM*.
* Open. You can then make changes to the template in the Source Editor. zPby+BP
*/ 3Ua?^2l
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package com.tot.count; R;< q<i_l
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/** X6Ha C+P
* vF72#BNs
* @author XNz+a|cF
*/ cQU/z"?+
public class CountBean { Lljn\5!r<
private String countType; xRh 22z
int countId; -k'<6op
/** Creates a new instance of CountData */ y4^u&0}0$
public CountBean() {} xcB\Y:
public void setCountType(String countTypes){ {9x_E {
this.countType=countTypes; }9fa]D-a?
} TKDG+`TyZ
public void setCountId(int countIds){ wI%M3XaBws
this.countId=countIds; /5@YZ?|#2
} Uj!3MF
public String getCountType(){ cn'>dz3v
return countType; F? #3
} mQ[$U
public int getCountId(){ qmrT dG
return countId; >xFvfuyC
} `[/#,*\
} U&^q#['
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CountCache.java r4yz{^G
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/* eaw!5]huu
* CountCache.java 6!<I'M'[e
* w~3X
m{
* Created on 2007年1月1日, 下午5:01 ]J7qsMw
* e"
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* To change this template, choose Tools | Options and locate the template under :'%6
* the Source Creation and Management node. Right-click the template and choose IiYL2JS;t|
* Open. You can then make changes to the template in the Source Editor. G~9m,l+
*/ "HOZ2_(o
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package com.tot.count; jPh<VVQ$@
import java.util.*; SB62(#YR
/** )GP;KUVae
* !:(+#
* @author [,=?e
*/ @*;x1A-]V
public class CountCache { i<uU_g'M
public static LinkedList list=new LinkedList(); bt}8ymcG
/** Creates a new instance of CountCache */ 9b.
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public CountCache() {} ~f<']zXv
public static void add(CountBean cb){ iOfm:DTPr
if(cb!=null){ (i&+= +"wn
list.add(cb); AL]gK)R
} f:;-ZkIU ?
} K?.~}82c
} EP>u% ]#
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CountControl.java Z-@nXt
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/* ~Ztn(1N
* CountThread.java x'|ty[87
* :H}iL*
* Created on 2007年1月1日, 下午4:57 0R?1|YnB
* {vu\qXmMv
* To change this template, choose Tools | Options and locate the template under ?9 huuJs7
* the Source Creation and Management node. Right-click the template and choose SioeIXU
* Open. You can then make changes to the template in the Source Editor. [S6u:;7
*/ ?:R ]p2 ID
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package com.tot.count; d)
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import tot.db.DBUtils; gawY{Jr8I
import java.sql.*; P1F-Wy1
/** Ym'h
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* 1_Yx]%g<
* @author BM :x`JY
*/ A
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public class CountControl{ W8W7<ml0A
private static long lastExecuteTime=0;//上次更新时间 Vgm*5a6t
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 LnR>!0:c
/** Creates a new instance of CountThread */ ~WA@YjQ]
public CountControl() {} c=sV"r?
public synchronized void executeUpdate(){ \M`qaFan5^
Connection conn=null; @eYpARF
PreparedStatement ps=null; .}__XWK5
try{ Ip8ml0oG
conn = DBUtils.getConnection(); Nm)3
conn.setAutoCommit(false); juEPUsE
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 1l-5H7^w2?
for(int i=0;i<CountCache.list.size();i++){ LL<xygd
CountBean cb=(CountBean)CountCache.list.getFirst(); }geb959
CountCache.list.removeFirst(); mSYjc)z
ps.setInt(1, cb.getCountId()); GvVkb=="
ps.executeUpdate();⑴ 0U=wGIO
//ps.addBatch();⑵ O:?3B!wF
} z:Am1B
//int [] counts = ps.executeBatch();⑶ #*h\U]=VS
conn.commit(); +Tum K.
}catch(Exception e){ ZSf &M
e.printStackTrace(); ~b_DFj
} finally{ Yjoe|
try{ '5h`="
if(ps!=null) { rC8p!e.yL
ps.clearParameters(); &nEL}GM)E
ps.close(); #xtH6\X
ps=null; eiK_JPF A-
} Xs2}n^#i
}catch(SQLException e){} )oIh?-WL
DBUtils.closeConnection(conn); #eW
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} wR%Ta -
} jOGdq;|
public long getLast(){ --$* q"
return lastExecuteTime; 2U)n^
} oC5h-4~
public void run(){ _a$qsY
long now = System.currentTimeMillis(); wI@87&
if ((now - lastExecuteTime) > executeSep) { &g|[/~dIr
//System.out.print("lastExecuteTime:"+lastExecuteTime); ceUe*}\cr
//System.out.print(" now:"+now+"\n"); 9q"kM
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Ty g>Xv
lastExecuteTime=now; I}PI
executeUpdate(); "\wMs
} NY7yk3
else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {lf{0c$X.
} &jJu=6 U
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} (%6fMVp
} A-!e$yz>
//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 >pF* unC;
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类写好了,下面是在JSP中如下调用。 U}w'/:H
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<%
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CountBean cb=new CountBean(); Y5aG^wE[:
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^8
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CountCache.add(cb); D40 vCax^J
out.print(CountCache.list.size()+"<br>"); Bve|+c6W
CountControl c=new CountControl(); D7hTn@I
c.run(); b6-N2F1Fs
out.print(CountCache.list.size()+"<br>"); n{gEIUo#
%>