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: vLIaTr gz
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CountBean.java KsQn %mxS
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/* Pos(`ys;
* CountData.java h9kwyhd"
* \49s;\I]
* Created on 2007年1月1日, 下午4:44 B^@X1EE
* Xbu P_U'
* To change this template, choose Tools | Options and locate the template under >Xi/ p$$7u
* the Source Creation and Management node. Right-click the template and choose UsgrI>|l
* Open. You can then make changes to the template in the Source Editor. TjS&V
*/ G=PX'dS
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package com.tot.count; rGlnu.mK^
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/** [Om,Q<
* a5?Yh<cJ
* @author a=
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*/ nL+y"O
public class CountBean { 6z2%/P-'
private String countType; @a (-U.CZ
int countId; ldt]=Sqy
/** Creates a new instance of CountData */ AP+%T
public CountBean() {} $]gflAe2
public void setCountType(String countTypes){ Gq-~zmg
this.countType=countTypes; (,D:6(R7t
} yX.; x 0
public void setCountId(int countIds){ HcM/
this.countId=countIds; 5'/ff=
} jI%glO'2
public String getCountType(){ *iVEO
return countType; yof8L WXx
} Nxr\Yey
public int getCountId(){ NqM=Nu\
return countId; "V`5 $ur
} rV}&G!V_t
} W<:x4gBa
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CountCache.java U(2=fKK;
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/* ajW2HH*9}A
* CountCache.java kS4YxtvB
* 40G'3HOp
* Created on 2007年1月1日, 下午5:01 x/ix%!8J
* .Nk5W%7]=
* To change this template, choose Tools | Options and locate the template under 1Gy
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* the Source Creation and Management node. Right-click the template and choose B Q2N_*v
* Open. You can then make changes to the template in the Source Editor. /[A#iTe
*/ K[S)e!\.
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package com.tot.count; R>B6@|}?
import java.util.*; h@dy}Id
/** e~geBlLar
* j/;wxKW
* @author 5?m4B:W
*/ EHK+qrym
public class CountCache { :LCyxLI
public static LinkedList list=new LinkedList(); 0i>p1/kv
/** Creates a new instance of CountCache */ ~ ReX$9
public CountCache() {} ]3~u @6
public static void add(CountBean cb){ Y
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if(cb!=null){ C;~LY&=
list.add(cb); tIS.,CEQF
} 5A+@xhRf
} *T~b
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} _*Ej3=u
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CountControl.java n=?wX#rEC#
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/* |g'ceG-
* CountThread.java 3H|drj:KV
* R_b4S%jhx
* Created on 2007年1月1日, 下午4:57 yMt:L)+
* 13pu{Xak
* To change this template, choose Tools | Options and locate the template under c
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* the Source Creation and Management node. Right-click the template and choose `g<0FQA
* Open. You can then make changes to the template in the Source Editor. frc9
*/ b,X+*hRt
\VWgF)_
package com.tot.count; 7Ah
import tot.db.DBUtils; LTB
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import java.sql.*; Bg}l$?S
/** &G?"I%Vw
* n6G&c4g<"
* @author x~=Mn%Ew0
*/ Ze <)B
*
public class CountControl{ 7$x%A&]
private static long lastExecuteTime=0;//上次更新时间 1OV] W
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 [SD
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/** Creates a new instance of CountThread */ *Q#oV}D_
public CountControl() {} q]Kv.x]$R
public synchronized void executeUpdate(){ a_-@rceU
Connection conn=null; w|Ry)[
PreparedStatement ps=null; f8ZuG !U
try{ 5~ZzQG
conn = DBUtils.getConnection(); qOIVuzi*
conn.setAutoCommit(false); ;NE4G;px4<
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 5A<}*T
for(int i=0;i<CountCache.list.size();i++){ 3Yo)K
CountBean cb=(CountBean)CountCache.list.getFirst(); 5 D=r7
CountCache.list.removeFirst(); -9;?k{{[T
ps.setInt(1, cb.getCountId()); {rK]Q! yj
ps.executeUpdate();⑴ (UCCEQq5
//ps.addBatch();⑵ LzDRy L
} T+B8SZw#}!
//int [] counts = ps.executeBatch();⑶ q|0l>DPRp
conn.commit(); K]uH7-YvL/
}catch(Exception e){ OMM5ALc(F
e.printStackTrace(); 5=I"bnIU
} finally{ 62MQ+H
try{ 0
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if(ps!=null) { \hn$-'=4
ps.clearParameters(); 78r0K 5=
ps.close(); +25=u|#4r
ps=null; e-OKv#]
} 1z0|uc
}catch(SQLException e){} kKjcW` [
DBUtils.closeConnection(conn); OCq5}%yU&i
} Y]5spqG
} 5W$Jxuyqj
public long getLast(){ h-RhmQA=Iz
return lastExecuteTime; Sk)lT^by
} {> 8?6m-
public void run(){ Z/!awf>
long now = System.currentTimeMillis(); *_7/'0E(3
if ((now - lastExecuteTime) > executeSep) { c{ +bY.J
//System.out.print("lastExecuteTime:"+lastExecuteTime); 8vtembna4
//System.out.print(" now:"+now+"\n"); a>rDJw:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); I>##iiKN
lastExecuteTime=now; 7\[fjCg\w
executeUpdate(); hgzNEx%^q
} qozvNJm)
else{ y. 1F@w|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); MT:VQ>fC
} UO#`Ak
} QleVW
} ,I ][
//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 >]&Ow9-
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类写好了,下面是在JSP中如下调用。 k{=dV
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<% Lis>Qr
CountBean cb=new CountBean(); ``I[1cC
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); (9kR'kr
CountCache.add(cb); WUo\jm[yr
out.print(CountCache.list.size()+"<br>"); >\3\&[#"
CountControl c=new CountControl(); Ok|Dh;1_
c.run(); VIN0kRQ#
out.print(CountCache.list.size()+"<br>"); bar=^V)
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