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:
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CountBean.java (X8N?tJ
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/* }N[sydL
* CountData.java )*uI/E
* bIH2cJ
* Created on 2007年1月1日, 下午4:44 1{wy%|H\
* 5xiYCOy
* To change this template, choose Tools | Options and locate the template under y`N1I
* the Source Creation and Management node. Right-click the template and choose Z`
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* Open. You can then make changes to the template in the Source Editor. (*EN! -/
*/ Ii9vA ^53
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package com.tot.count; 6hZhD1lDG^
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/** cr!I"kTgD
* QEVjXJOt0
* @author R =jK3yfw
*/ AkF1Hj
public class CountBean { %8ul}}d9
private String countType; |`|b&Rhu
int countId; ;R67a
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/** Creates a new instance of CountData */ $OJ*Kul
public CountBean() {} o%dtf5}(,
public void setCountType(String countTypes){ >ko;CQR
this.countType=countTypes; ."lY>(HJ
} ED6H
public void setCountId(int countIds){ Q.N^1?(>k
this.countId=countIds; WgIVhj
} V=c&QPP
public String getCountType(){ f="}.
return countType; ;9^B# aTM
} 0e:aeLh
public int getCountId(){ 6(z.(eT
return countId; N5s_o0K4TU
} G6
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} c" l~=1Dr
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CountCache.java )yK!EK\
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/* w "D"9G
* CountCache.java ~(^[TuJC
* Ro1l:P)C`
* Created on 2007年1月1日, 下午5:01 [)a,rrhj
* GY!&H"%
* To change this template, choose Tools | Options and locate the template under _x lgsa
* the Source Creation and Management node. Right-click the template and choose `wq\K8v
* Open. You can then make changes to the template in the Source Editor. 7W>T=
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*/ Op|Be
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package com.tot.count; WcdU fv(>
import java.util.*; PCES&|*rf
/** =#W{&Te;
* 9KP+
* @author cO<x:{`
*/ ZF`ckWT:-N
public class CountCache { -AbA6_j
public static LinkedList list=new LinkedList(); 6q5V*sJ&
/** Creates a new instance of CountCache */ Z?b.
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public CountCache() {} ~E)I+$,
public static void add(CountBean cb){ a{HvrWs?Q
if(cb!=null){ u_uC78`p
list.add(cb); _[<I&^%
} }3+(A`9h f
} I[R?j?$}>
} 3~
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CountControl.java gKPV*
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/* *BF1Sso
* CountThread.java f[z#=zv
* 3U}z?gP[
* Created on 2007年1月1日, 下午4:57 >s{[d$
* lUp 7#q
* To change this template, choose Tools | Options and locate the template under :gR`rc!
* the Source Creation and Management node. Right-click the template and choose #de]b
* Open. You can then make changes to the template in the Source Editor. zRKg>GG`
*/ 2Gj&7A3b
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package com.tot.count; yXkgGY5
import tot.db.DBUtils; X`22Hf4ct
import java.sql.*; k<St:X%.O
/** #)\KV7f!;
* vg)zk2O
* @author x|Q6[Y
*/ Y!SD^Ie7!
public class CountControl{ Pukq{/27
private static long lastExecuteTime=0;//上次更新时间 =]D##R
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 I*0W\Qz@
/** Creates a new instance of CountThread */ %Jw;c`JM
public CountControl() {} & MAIm56~
public synchronized void executeUpdate(){ iA:CPBv_mu
Connection conn=null; H
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PreparedStatement ps=null; W}EO]A%f.\
try{ $1w8GI\J
conn = DBUtils.getConnection(); $[z*MQ
conn.setAutoCommit(false); 63at
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 1sgoT f%
for(int i=0;i<CountCache.list.size();i++){ J${wU@_%
CountBean cb=(CountBean)CountCache.list.getFirst(); *<9p88FpDU
CountCache.list.removeFirst(); QN0Ik 2L
ps.setInt(1, cb.getCountId()); #$8tBo
ps.executeUpdate();⑴ l
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//ps.addBatch();⑵ jx-W$@
} K%Rx5 S
//int [] counts = ps.executeBatch();⑶ ' rXkTm1{
conn.commit(); 0z,c6MjM+
}catch(Exception e){ $bN%x/
e.printStackTrace(); / ]I]
} finally{ Z'u`)jR
try{ B^KC~W
if(ps!=null) { <yIJ$nBx
ps.clearParameters(); WJ
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ps.close(); nc`[f y|}
ps=null; `OBDx ^6F
} $#0%gs/x
}catch(SQLException e){} =LuA[g
DBUtils.closeConnection(conn); $ccI(J`zux
} V{(ve#y7`{
} Ao0F? 2|
public long getLast(){ T,;6q!s=
return lastExecuteTime; inp= -
} ;8UNM
public void run(){ `f b}cJUa
long now = System.currentTimeMillis(); s'i1!GNF
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if ((now - lastExecuteTime) > executeSep) { thkL<
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9g>ay-W[(
//System.out.print(" now:"+now+"\n"); 0C0iAp
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); BB~Qs
lastExecuteTime=now; Ha;^U/0|
executeUpdate();
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} 6W~F
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else{ 9=h A#t.#
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /*st,P$"
} }bHdU]$}
} =_TCtH
} ;zs4>>^>
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 u dH7Q&"
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类写好了,下面是在JSP中如下调用。 +]B^*99
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<% uYJ6"j
CountBean cb=new CountBean(); dGZVWEaPfx
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ;@Ls"+g
CountCache.add(cb); uTOL
out.print(CountCache.list.size()+"<br>"); .\i9}ye
CountControl c=new CountControl(); y|c]r!A
c.run(); _e/vw:
out.print(CountCache.list.size()+"<br>"); m,Os$>{Ok
%>