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: &N\4/'wV
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CountBean.java {>8u/
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/* mYw9lM
* CountData.java Z9k"&F~u}
* {[$JiljD
* Created on 2007年1月1日, 下午4:44 4I7;/ZgALQ
* /I@Dv?
* To change this template, choose Tools | Options and locate the template under }S}9Pm,:
* the Source Creation and Management node. Right-click the template and choose /Lt Lu
* Open. You can then make changes to the template in the Source Editor. 1-:{&!
*/ 'c&S%Ra[3G
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package com.tot.count; Ct\n1T }
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/** NI33lp$V
* VVVw\|JB>
* @author PDtLJt$
*/ {j4J(dtO
public class CountBean { qe_59'K
private String countType; <WGx
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int countId; {3R?<ET]mt
/** Creates a new instance of CountData */ ED=P
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public CountBean() {} -9@/S$i
public void setCountType(String countTypes){ Mr
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this.countType=countTypes; 8>l#F<@5
} jO+#$=C
public void setCountId(int countIds){ wTK>U`o
this.countId=countIds; {((|IvP`
} t?6_^ 08
public String getCountType(){ a?5R;I B
return countType; }`*DMI;-
} ("5Eed
public int getCountId(){ 9&7$oI$!J
return countId; hB 36o9|9
} OF/DI)j3
} mjXO}q7
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CountCache.java 8@Hl0{q
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/* (J,^)!g7
* CountCache.java ,!'L~{
* iQj2aK Gs
* Created on 2007年1月1日, 下午5:01 [|E|(@J
* =!Ce#p?h,
* To change this template, choose Tools | Options and locate the template under dPO|x+N,
* the Source Creation and Management node. Right-click the template and choose `ot<BwxJ
* Open. You can then make changes to the template in the Source Editor. Md(h-wYr
*/ y`Km96Ui
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package com.tot.count; 'H.,S_v1x
import java.util.*; $9m>(b/;n
/** ^s[OvJb
* .GH#`j
* @author R<FW?z*
*/ +Oa+G.;)o4
public class CountCache { NP< {WL#
public static LinkedList list=new LinkedList(); l7M![Ur
/** Creates a new instance of CountCache */
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public CountCache() {} QH.zsqf(
public static void add(CountBean cb){ T3#KuiwU9
if(cb!=null){ "{Jq6):mp
list.add(cb); ZXL
} )mvD2]fK
} Tyk\l>S
} ]<B@g($
* M,'F^E2
CountControl.java 2,.;Mdl
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/* #V:28[
* CountThread.java QXg9ah~
* s!Y`1h{
* Created on 2007年1月1日, 下午4:57 )/_T`cN
* whdoG{/
* To change this template, choose Tools | Options and locate the template under U9:w ^t[Pp
* the Source Creation and Management node. Right-click the template and choose vh"> Z4
* Open. You can then make changes to the template in the Source Editor. :L'U>)k
*/ Y,;$RV@g
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package com.tot.count; byB
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import tot.db.DBUtils; ZuIw4u(9
import java.sql.*; R;2q=%
/** 01;
* iD-,C`
* @author uiEAi
*/ oGa8#>
public class CountControl{ ^geC?m
private static long lastExecuteTime=0;//上次更新时间 }:f
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;S_\-
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/** Creates a new instance of CountThread */ rW<sQ0
public CountControl() {} $b=4_UroS
public synchronized void executeUpdate(){ *4oj '}
Connection conn=null; t3b64J[A{
PreparedStatement ps=null; UI}df<Ge
try{ ~|t7
conn = DBUtils.getConnection(); ^N`bA8
conn.setAutoCommit(false); ZlxJY%oeu
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); s1| +LT,D
for(int i=0;i<CountCache.list.size();i++){ r"uOf;m
CountBean cb=(CountBean)CountCache.list.getFirst(); Z+ ?V10$
CountCache.list.removeFirst(); cm!|A)~
ps.setInt(1, cb.getCountId()); <!qv$3/7
ps.executeUpdate();⑴ 4_'($FC1
//ps.addBatch();⑵ 2&Hn%q)
} +o7Np|Ou
//int [] counts = ps.executeBatch();⑶ 7UzbS,$x
conn.commit(); X'W8 mqk
}catch(Exception e){ eO?.8OM-a
e.printStackTrace(); 5C&]YT3)
} finally{ j9XRC9
try{ eYD|`)-f<^
if(ps!=null) { `3KXWN`.s
ps.clearParameters(); _T)G?iv:&
ps.close(); 2A^>>Q/,u
ps=null; \vR&-+8dk
} +o94w^'^$b
}catch(SQLException e){} Z F&aV?
DBUtils.closeConnection(conn); a&*fk ?o
} 43p0k&;-7
} XKEd~2h<y
public long getLast(){ )1!jv!
return lastExecuteTime; H*M )<"X
} 4LfD{-_uW
public void run(){ !0+!%Nr>J
long now = System.currentTimeMillis(); ;#F7Fp *U
if ((now - lastExecuteTime) > executeSep) { ?'L3B4
//System.out.print("lastExecuteTime:"+lastExecuteTime); o;D[F
//System.out.print(" now:"+now+"\n"); tnCGa%M
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); k25:H[
lastExecuteTime=now; =eNh))]
executeUpdate(); a?]"|tQ'
} ;E{k+vkqy
else{ j>KJgSs]&\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]*M-8_D
} ">LX>uYmX-
} 1aQR9zg%
} ![OKmy
//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 7Y>17=|
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类写好了,下面是在JSP中如下调用。 S3oSc<&2
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<% 3TDjWW;#~
CountBean cb=new CountBean(); @TTB$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }%;o#!<N(@
CountCache.add(cb); V&75n.L
out.print(CountCache.list.size()+"<br>"); j~ )GZV
CountControl c=new CountControl(); uR:@7n
c.run(); MI,b`pQ
out.print(CountCache.list.size()+"<br>"); Q{~ WWv
%>