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: ~]C%/gEh
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CountBean.java IuF_M<d,
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/* :Y,BdU
* CountData.java /Ci*Az P
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* Created on 2007年1月1日, 下午4:44 8T)&`dM6P~
* T:]L/wCj
* To change this template, choose Tools | Options and locate the template under BQH}6ueZ
* the Source Creation and Management node. Right-click the template and choose F[
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* Open. You can then make changes to the template in the Source Editor. "XgmuSQ!
*/ b89a)k>^g
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package com.tot.count; ?S$i?\Qh
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/** )rW&c-'
* :r#)z4d5
* @author azQ D>
*/ 0|&\'{
public class CountBean { 8lF\v /vN
private String countType; 1NQbl+w#I
int countId; 'y]\-T
/** Creates a new instance of CountData */ FTc.]laO
public CountBean() {} mrIh0B:`
public void setCountType(String countTypes){ 7\]E~/g
this.countType=countTypes; 7/7Z`
} t\P<X^d%
public void setCountId(int countIds){ *Xo]-cKL0
this.countId=countIds; (+uj1z^
} tGA :[SP
public String getCountType(){ [r+ZE7$2b"
return countType; hpTDxh'?$C
} :cu#V
public int getCountId(){ qyC=(v
return countId; 'r1LSht'
} !`1'2BC
} 8r"+bhGx~
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CountCache.java No]~jnqDM
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/* /~*_x=p:
* CountCache.java jZ`;Cy\<B
* v>z tB,,9
* Created on 2007年1月1日, 下午5:01 akw,P$i
* 3rLTF\
* To change this template, choose Tools | Options and locate the template under HbP!KVHyk1
* the Source Creation and Management node. Right-click the template and choose s,#>m*Rh
* Open. You can then make changes to the template in the Source Editor. <)+y=m\eJ
*/ +)zOer,
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package com.tot.count; t!Sq A(-V
import java.util.*; V%$/#sza
/** -*5Rnx|Y{
* .920{G?l5
* @author bR@p<;G|
*/ ]smkTo/
public class CountCache { qC
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public static LinkedList list=new LinkedList(); [Nn`l,
/** Creates a new instance of CountCache */ }neY<{z
public CountCache() {} c'/l,k
public static void add(CountBean cb){ C8FB:JNJV
if(cb!=null){ __mF?m
list.add(cb); (/35pg6\
} @gY)8xMbA
} 4pw6bK,s2\
} q6YX M
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CountControl.java MSf;ZB
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/* N F)~W#
* CountThread.java :y7c k/>
* w$JvB5O
* Created on 2007年1月1日, 下午4:57 H":oNpfb
* 3R+|5Uq8~
* To change this template, choose Tools | Options and locate the template under 2-Y<4'>
* the Source Creation and Management node. Right-click the template and choose TB0
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* Open. You can then make changes to the template in the Source Editor. !K|5bK
*/ mI 74x3 [
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package com.tot.count; oudxm[/U
import tot.db.DBUtils; lNSLs"x^
import java.sql.*; m2AnXY\
/** 8WnwQ%;m?
* L3CP`cx
* @author ZP{*.]Qu
*/ ~"A+G4jl
public class CountControl{ vVOh3{e|
private static long lastExecuteTime=0;//上次更新时间 '],J$ge
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @S|XGf
/** Creates a new instance of CountThread */ 1GzAG;UUo6
public CountControl() {} y5!KX AQ%
public synchronized void executeUpdate(){ a+n0|CvF
Connection conn=null; T=ev[ mS
PreparedStatement ps=null; W6Y]N/v3>
try{ JtER_(.
conn = DBUtils.getConnection(); |\pbir
conn.setAutoCommit(false); #U14-^7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 3Z1CWzq(
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); ` V##Y
CountCache.list.removeFirst(); .V,@k7U,V
ps.setInt(1, cb.getCountId()); FSND>\>
ps.executeUpdate();⑴ p,#o<W
//ps.addBatch();⑵ P&f7@MOV.P
} 4:FK;~wM&x
//int [] counts = ps.executeBatch();⑶ ~@}Bi@*
conn.commit(); 5{g?,/(
}catch(Exception e){ %7|9sQ:
e.printStackTrace(); rW$[DdFA5{
} finally{ FJMrs[
try{ \-g)T}g,I
if(ps!=null) { .mR8q+I6
ps.clearParameters(); <7~'; K
ps.close(); q<M2,YrbAI
ps=null; WPQ fhr#|
} a|X a3E
}catch(SQLException e){} /'/Xvm3
DBUtils.closeConnection(conn); $&=S#_HQS
} LGn:c;
} n@)K #
public long getLast(){ 'dn]rV0(C
return lastExecuteTime; DMO Mh#[
} kDsFR#w&`
public void run(){ \.-bZ$
long now = System.currentTimeMillis(); T:~vk.Or
if ((now - lastExecuteTime) > executeSep) { w(L4A0K[
//System.out.print("lastExecuteTime:"+lastExecuteTime); :>5@cvc
//System.out.print(" now:"+now+"\n"); ,y#Kv|R
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); P5UL4uyl
lastExecuteTime=now; {z{bY\
executeUpdate(); A6thXs2
} A*\.NTM
else{ z:wutqru
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); %%[LKSTb
} x<ZJb
} -Fe?R*-g
} XuFYYx~ ^3
//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 )P
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类写好了,下面是在JSP中如下调用。 lNYt`xp
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<% 9P+-#B
CountBean cb=new CountBean(); vQ
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); xA$XT[D
CountCache.add(cb); 4\iOeZRf
out.print(CountCache.list.size()+"<br>"); EFM5,gB.m
CountControl c=new CountControl(); YpVD2.jy
c.run(); ,
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out.print(CountCache.list.size()+"<br>"); ZQV6xoN;r
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