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: JV&Zwbu
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CountBean.java ,}u,)7
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/* gji*Wq
* CountData.java }M^_Z#|,
* 1E8$% 6VV
* Created on 2007年1月1日, 下午4:44 /9P^{OZ;y
* A0S8Dh$
* To change this template, choose Tools | Options and locate the template under 8~;{xYN )
* the Source Creation and Management node. Right-click the template and choose AjG)1
* Open. You can then make changes to the template in the Source Editor. 7,f:Qi@g
*/ h,]tQ#!s8
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package com.tot.count; ]F
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/** JR])xPI`
* Kq$:\B)<c
* @author cD5w| rm?i
*/ ES^NBI j5P
public class CountBean { EN)YoVk
private String countType; KuIkul9^%
int countId; 93 [rL+l.Y
/** Creates a new instance of CountData */ h>~jQ&\M
public CountBean() {} Fs?( UM
public void setCountType(String countTypes){ nT_*EC<.
this.countType=countTypes; F
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} p@vpd
public void setCountId(int countIds){ " 98/HzR
this.countId=countIds; K1/
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} uFz/PDOZ@
public String getCountType(){ JvKO $^
return countType; *@CVYJ'<
} ?){0-A4
public int getCountId(){ fDL3:%D
return countId; Yd[U
} ~(stA3]k
} u.$Ym
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CountCache.java bh{E&1sLh
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/* G}182"#4
* CountCache.java C\y[&egww
* 2=jd;2~
* Created on 2007年1月1日, 下午5:01 kZJt~}
* eH ;Wfs2f
* To change this template, choose Tools | Options and locate the template under o^8*aH)I>Y
* the Source Creation and Management node. Right-click the template and choose 4 U3C~J
* Open. You can then make changes to the template in the Source Editor. Tw2Xe S
*/ 0Ulxp
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package com.tot.count; $Vo/CZW7
import java.util.*; 8FAT(f//.
/** ^!q 08`0
* eVJ= .?r
* @author NKRaQr
*/ c'"#q)
public class CountCache { ,jAx%]@,I
public static LinkedList list=new LinkedList(); !>CE(;E>z
/** Creates a new instance of CountCache */ V+Y|4Y&
public CountCache() {} R
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public static void add(CountBean cb){ XPar_8I
if(cb!=null){ d^ 2u}^kG
list.add(cb); s>LA3kT
} uCY(:;[<
} F~tm`n8Z
} @~JB\j9
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CountControl.java y2oB]^z&n
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/* KK@
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* CountThread.java K4iI:
* eKL]E!
* Created on 2007年1月1日, 下午4:57 3Cq6h;!#
* ^RY n8I
* To change this template, choose Tools | Options and locate the template under lF0K=L
* the Source Creation and Management node. Right-click the template and choose D."cQ<sxpN
* Open. You can then make changes to the template in the Source Editor. _{N0OX
*/ T+`xr0
*!._Ais,\
package com.tot.count; "9c.C I
import tot.db.DBUtils; !Sh^LYqn
import java.sql.*; 8:Z@ lp^
/** lc\>DH\n6
* i58ZV`Rk`
* @author s/r5,IFR
*/ F% F
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public class CountControl{ mle_*Gy8
private static long lastExecuteTime=0;//上次更新时间 LXBbz;vYl
private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ 3r,1^h
public CountControl() {} kWzuz#
public synchronized void executeUpdate(){ ^VSt9&
Connection conn=null; jA20c(O
PreparedStatement ps=null; cpE25
try{ l=oN X"l=
conn = DBUtils.getConnection(); #E-
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conn.setAutoCommit(false); @5{.K/s
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); )e4WAlg8c
for(int i=0;i<CountCache.list.size();i++){ ti$oZ4PpF
CountBean cb=(CountBean)CountCache.list.getFirst(); !!?+M @
CountCache.list.removeFirst(); Q'n(^tbL
ps.setInt(1, cb.getCountId()); /#S4espE
ps.executeUpdate();⑴ W?*Xy6",JF
//ps.addBatch();⑵ 8>C;
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} pFpQ\xc9$
//int [] counts = ps.executeBatch();⑶ RB S[*D
conn.commit(); (z8]FT
}catch(Exception e){ _n-VgPRn
e.printStackTrace(); c!'A)JD@
} finally{ 5~ _eN
try{ t9Enk!@
if(ps!=null) { %8}WX@SB
ps.clearParameters(); !Z<mrr;T@
ps.close(); &+)+5z_d
ps=null; no~O R Q
} {AU` }*5
}catch(SQLException e){} ]FY?_DGOA
DBUtils.closeConnection(conn); nUI63?
} KuIt[oM
} _aXP
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public long getLast(){ l _kg3e4
return lastExecuteTime; T..N*6<X
} |'V<>v.v
public void run(){ 2ru*#Z#(
long now = System.currentTimeMillis(); ql#{=oGDnA
if ((now - lastExecuteTime) > executeSep) { c]AKeq]
//System.out.print("lastExecuteTime:"+lastExecuteTime); A%NK0j$;}
//System.out.print(" now:"+now+"\n"); P.[6s$J
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); w>NZRP_3
lastExecuteTime=now; \N#
HPrv}
executeUpdate(); <;$Sa's,LE
} ue6/EN;}
else{ jQ.>2-;H9
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Xm"w,J&
} ,(@Y%UW:
} [M7iJcwt
} M-&^
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 dvg;
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类写好了,下面是在JSP中如下调用。 C&gOA8nf
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<% _g^K$+F'}
CountBean cb=new CountBean();
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >j(I[_g
CountCache.add(cb); z. _C*c
out.print(CountCache.list.size()+"<br>"); G:h;C].
CountControl c=new CountControl(); SxLHFN]
c.run(); %T&&x2p^=?
out.print(CountCache.list.size()+"<br>"); FT3,k&i
%>