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: -VvN1G6.x?
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CountBean.java 1Q7]1fRu
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/* $"g'C8
* CountData.java M7=|N:/_
* nP0rg
* Created on 2007年1月1日, 下午4:44 +t8#rT ^B
* A3.*d:A
* To change this template, choose Tools | Options and locate the template under n^Q-K}!T/
* the Source Creation and Management node. Right-click the template and choose >J_(~{-sNG
* Open. You can then make changes to the template in the Source Editor. ZU;nXqjc
*/ };g<|v*o
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package com.tot.count;
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/** j/F:j5O*
* "}2I0tM
* @author SNC)cq+{
*/ Jo\karpb
public class CountBean { 8(]q/g"O
private String countType; i7mo89S
int countId; _~ 3r*j
/** Creates a new instance of CountData */ p2hPLq
public CountBean() {} ^@)*voP#G
public void setCountType(String countTypes){ Y o\%53w/
this.countType=countTypes; }J6 y NoXu
} $mxl&Qr>Q;
public void setCountId(int countIds){ $ncP#6
this.countId=countIds; XrJLlH>R4
} )3ZkKv;zY
public String getCountType(){ a28`)17z
return countType; [&)*jc16
} @+sYwlA~
public int getCountId(){ BD [<>Wm
return countId; s8;*Wt
} A$rCo~Ek
} ]f6,4[
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CountCache.java A#gy[.Bb
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/* xmejoOF
* CountCache.java CUx-k|\
* .ZupsS9l
* Created on 2007年1月1日, 下午5:01 Hq|{Nt%Q
* }?*$AVs2q
* To change this template, choose Tools | Options and locate the template under 'VV"$`Fu"
* the Source Creation and Management node. Right-click the template and choose <CWOx&hr
* Open. You can then make changes to the template in the Source Editor. tlgg~MViS
*/ ^*F'[!. p
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package com.tot.count; {[bB$~7Eu
import java.util.*; v7<r-<I[
/** p3qKtMs0!
* g6@^n$Y
* @author *t`=1Ioj
*/ k/i&e~! \
public class CountCache { xu@+b~C\
public static LinkedList list=new LinkedList(); .SDE6nvbW
/** Creates a new instance of CountCache */ MC1&X'
public CountCache() {} @DKph!cr
public static void add(CountBean cb){ x??H%'rP
if(cb!=null){ ~BgNMO;|
list.add(cb); \^dYmU
} 0U!_ o2]
} {Hz;*1?$k
} T3t
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CountControl.java ,7;euV5X
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/* }^`5$HEi
* CountThread.java jSw>z`'#H
* <1<0 odB
* Created on 2007年1月1日, 下午4:57 M&KJZ
* /}S1e P6
* To change this template, choose Tools | Options and locate the template under EQX?Zs?C
* the Source Creation and Management node. Right-click the template and choose q&esI
* Open. You can then make changes to the template in the Source Editor. a``Q}.ST
*/ pwl7aC+6d
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package com.tot.count; %1rN6A!%
import tot.db.DBUtils; ,qIut|C*
import java.sql.*; j|VX6U
/** tdNAR|
* {m"I-VF
* @author w}?,N
*/ 1~S''[
public class CountControl{ 0NXaAf:2Z
private static long lastExecuteTime=0;//上次更新时间 '\P+Bu]6&
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 [6%y RQ_
/** Creates a new instance of CountThread */ ?+L7Bd(EF%
public CountControl() {} Mlo:\ST|
public synchronized void executeUpdate(){ +<3e@s&
Connection conn=null; ?Skv2!X|
PreparedStatement ps=null; [@0Hmd7
try{ EE*FvI`
conn = DBUtils.getConnection(); X3l6b+p
conn.setAutoCommit(false); rfOrh^
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); yJ!,>OQ%'
for(int i=0;i<CountCache.list.size();i++){ <o@__l.
CountBean cb=(CountBean)CountCache.list.getFirst(); 8O0]hz
CountCache.list.removeFirst(); NZ-57Ji
ps.setInt(1, cb.getCountId()); } A}Vd:#
ps.executeUpdate();⑴ iThf\
//ps.addBatch();⑵ 3m"9q
} /KhY,G'Z
//int [] counts = ps.executeBatch();⑶ x";4)u=
conn.commit(); BLb'7`t
}catch(Exception e){ Ju_(,M-Vgr
e.printStackTrace(); ?$=Ml$
} finally{ h4c4!S
try{ @e+qe9A|
if(ps!=null) { \j0016;
ps.clearParameters(); nr%P11U\c
ps.close(); c22L]Sxo
ps=null; 21hTun"W
} >viLvDng
}catch(SQLException e){} o:@A% *jg
DBUtils.closeConnection(conn); e*39/B0S
} XXb,*u 3
} AZnFOS
public long getLast(){ T/q*k)IoR
return lastExecuteTime; %Z yt;p2
} jtPHk*>^wu
public void run(){ q^b12@.
long now = System.currentTimeMillis(); vZIx>
if ((now - lastExecuteTime) > executeSep) { o'ZW
//System.out.print("lastExecuteTime:"+lastExecuteTime); :-j/Y'H_
//System.out.print(" now:"+now+"\n"); /Tp>aW%}"
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
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lastExecuteTime=now; N._^\FRyn
executeUpdate(); {%z5^o1)
} 7/bF04~%
else{ la{o<||Aq
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); @XH@i+{B
} Gk)6ljL
} g?>
} C{YTHNn
//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 KXcE@q9
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类写好了,下面是在JSP中如下调用。 cB2~W%H
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<% Pa/2]) w
CountBean cb=new CountBean(); Zrq\:KxX
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 6W)#FO`
CountCache.add(cb); Su k;##I
out.print(CountCache.list.size()+"<br>"); |q 0iX2W
CountControl c=new CountControl(); qO>A6
c.run(); vcSb:('
out.print(CountCache.list.size()+"<br>"); }5y]kn
%>