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: oRZ98?Y\B
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CountBean.java H)k V8wU
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/* 5,R4:y ?cK
* CountData.java m'zve%G
* [XE\2Qa8e
* Created on 2007年1月1日, 下午4:44 "&:H }Jd
* xx@[ecW
* To change this template, choose Tools | Options and locate the template under hmkm^2
* the Source Creation and Management node. Right-click the template and choose ,njlKkFw^Z
* Open. You can then make changes to the template in the Source Editor. $b~[>S-Q
*/ s0O]vDTR,H
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package com.tot.count; 'NMO>[.
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/** {'p <
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* HLkI?mW<
* @author p#%*z~ui
*/ n)0M1o#
public class CountBean { '%X29B5
private String countType; >4#:qIU
int countId; %M3L<2
/** Creates a new instance of CountData */ '}^qz#w
public CountBean() {} }Y^o("c(
public void setCountType(String countTypes){ Q=61.lP6
this.countType=countTypes; = GyABK
} &]h`kvtBC
public void setCountId(int countIds){ d6a3\f
this.countId=countIds; z/]]u.UP
} I7wR[&L885
public String getCountType(){ jlA6~n
return countType; [Tl66Eyl
} eEBo:Rc9
public int getCountId(){ ~N%+ZXh&E
return countId; hFo29oN
} A`#?Bj
} eBH:_Ls_-^
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CountCache.java 2!6E~<~HC
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/* O/U? Wq
* CountCache.java HSWki';G
* {+m8^-T
* Created on 2007年1月1日, 下午5:01 UEx13!iFo
* 1>uAVPa
* To change this template, choose Tools | Options and locate the template under -g."{|
* the Source Creation and Management node. Right-click the template and choose 2F+"v?n=\
* Open. You can then make changes to the template in the Source Editor. ^mg:<_p
*/ I 12Zh7Cc:
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package com.tot.count; ?YMBZ
import java.util.*; `Se2f0",
/** @ta:9wZ
* :%z#s
* @author Lk!m1J5
*/ \FUMfo^
public class CountCache { 6J\ 2=c`
public static LinkedList list=new LinkedList(); Rc:}%a%e
/** Creates a new instance of CountCache */ Y=4
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public CountCache() {} Do7 7V5
public static void add(CountBean cb){ :tbgX;tCs5
if(cb!=null){ q 'd]
list.add(cb); ]ag{sU@#
} |{Ex)hkw
} x|yJCs>
} EjFn\|VK
}`2a>N:
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CountControl.java Z;V(YK(WO.
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/* w\MWr+4
* CountThread.java 4/%fpU2
* h=S7Z:IaM
* Created on 2007年1月1日, 下午4:57 I eJI-lo
* 0@!huk
* To change this template, choose Tools | Options and locate the template under 2*<Zc|uNW
* the Source Creation and Management node. Right-click the template and choose 8h0C G]
* Open. You can then make changes to the template in the Source Editor. eAo+w*D(
*/ OPzudO
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package com.tot.count; OX 'V
import tot.db.DBUtils; Y6&v&dA;
import java.sql.*; 'YB[4Q /0
/** PJ;WNo8
* 2GORGS%
* @author (c)=Do=
*/ 8HFCmY#
public class CountControl{ %L^( eTi[
private static long lastExecuteTime=0;//上次更新时间 h]h"-3
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g5y`XFY
/** Creates a new instance of CountThread */ Wlxmp['Bh
public CountControl() {} ;py9,Wno
public synchronized void executeUpdate(){ @!=Ds'MJC
Connection conn=null; &ocuZ-5`
PreparedStatement ps=null; {f\wIZ-K A
try{ L{P'mG=4
conn = DBUtils.getConnection(); p:TE##
conn.setAutoCommit(false); }ymW};W
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "5L?RkFi\
for(int i=0;i<CountCache.list.size();i++){ >t.Lc.
CountBean cb=(CountBean)CountCache.list.getFirst(); z]r'8Jc
CountCache.list.removeFirst(); v@|<.
ps.setInt(1, cb.getCountId()); D
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ps.executeUpdate();⑴ J}&U[ds p
//ps.addBatch();⑵ ,{!,%]bC
} :>.{w$Ln%
//int [] counts = ps.executeBatch();⑶ "d:rPJT)(@
conn.commit(); 41Z@_J|&
}catch(Exception e){ *ma
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e.printStackTrace(); 5\# F5s}
} finally{ %SOXw8-
try{ r@}`Sw]@
if(ps!=null) { >zqaV@T
ps.clearParameters(); 4/|x^Ky>G
ps.close(); BK%.wi
ps=null; `@
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} x;)I%c
}catch(SQLException e){} ?tY+P`S
DBUtils.closeConnection(conn); u>)h
} ']TWWwj$
}
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public long getLast(){ cN0
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return lastExecuteTime; 1R3,Z8j'
} !DzeJWM|
public void run(){ #<< el;n
long now = System.currentTimeMillis(); L&DjNu`!9
if ((now - lastExecuteTime) > executeSep) { Sc]K-]1(H
//System.out.print("lastExecuteTime:"+lastExecuteTime); iq*im$9J
//System.out.print(" now:"+now+"\n"); F$)l8}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 72d|Jbd
lastExecuteTime=now; &RYdSXM
executeUpdate(); V\Gs&>
} @JXpD8jn
else{ O\.^H/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); UP^8Yhdo
} !{r2`d09n)
} @Suz-j(H
} zawu(3?~)5
//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 Rpg g
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类写好了,下面是在JSP中如下调用。 +Q u.86dH
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<% ]B,tCBt
CountBean cb=new CountBean(); >Xk42zvqn
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); v']_)
CountCache.add(cb); oh< -&3Jn
out.print(CountCache.list.size()+"<br>"); {lWV H
CountControl c=new CountControl(); m;~} }~&vQ
c.run(); a5pl/d
out.print(CountCache.list.size()+"<br>"); vSR&>Q%X
%>