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: +x"uP
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CountBean.java n"EKVw7Y
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/*
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* CountData.java sW[-qPK<
* jfuHZ^ YA
* Created on 2007年1月1日, 下午4:44 qE~_}4\Z9
* y+(\:;y$7
* To change this template, choose Tools | Options and locate the template under eQbHf
* the Source Creation and Management node. Right-click the template and choose +Y%6y]8
* Open. You can then make changes to the template in the Source Editor. y"q
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*/ [r/zBF-.
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package com.tot.count; o:@Q1+p
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/** L|'^P3#7`
* >pU9}2fpT
* @author I/dy^5@F
*/ !a@)6or
public class CountBean { [C "\]LiX
private String countType; 3$\k=q3`#
int countId; 9"P|Csj
/** Creates a new instance of CountData */ bx3Q$|M?
public CountBean() {} <gp?}Lk
public void setCountType(String countTypes){ I_J&>}V'
this.countType=countTypes; [*',pG
} s6bsVAO>
public void setCountId(int countIds){
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this.countId=countIds; I^?tF'E
} g":[rXvId
public String getCountType(){ R+M&\ 5
return countType; W:d
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} BN_h3|)
public int getCountId(){ 9@
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return countId; 8+F5n!
} Kw
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} 4yl{:!la
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CountCache.java "7B}hZ^)W
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/* ]\78(_o.zz
* CountCache.java rJ!cma
* EbC!tR
* Created on 2007年1月1日, 下午5:01 >@YefNX6
* tEhg',2t(
* To change this template, choose Tools | Options and locate the template under qLN\%}69/
* the Source Creation and Management node. Right-click the template and choose A]z*#+Sl
* Open. You can then make changes to the template in the Source Editor. 7>E.0DP
*/ I%[e6qX@
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package com.tot.count; !/zRw-q3B
import java.util.*; *M.xVUPr
/** (eN7s_
* Cx7-I0!
* @author !U^{`V jp[
*/ V
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public class CountCache { A6&*VD
public static LinkedList list=new LinkedList(); 4qQ,1&!]S
/** Creates a new instance of CountCache */ G7 %bY
public CountCache() {} gYKz,$
public static void add(CountBean cb){ O `}EiyV
if(cb!=null){ O*EV~{K
list.add(cb); /A=w`[<
} PVCoXOqh
} @R[{
} JB_fS/I
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CountControl.java R?{+&r.X
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/* -pC8 L<
* CountThread.java 7{;it uqX
* ?"B]"%M&
* Created on 2007年1月1日, 下午4:57 ,lyW'<~gA
* :D.0\.p
* To change this template, choose Tools | Options and locate the template under z|l*5@p
* the Source Creation and Management node. Right-click the template and choose + ?1GscJ
* Open. You can then make changes to the template in the Source Editor. 8Lo#{`
*/ j|eA*UE
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package com.tot.count; \(o"/*
import tot.db.DBUtils; f-b],YE
import java.sql.*; /R)wM#&
/** >[}oH2oi
* YDt+1Kw}D
* @author y>^a~}Zq
*/ jwZ,_CK
public class CountControl{ 0I&k_7_
private static long lastExecuteTime=0;//上次更新时间 ^t;z;.g
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 V2MOD{Maat
/** Creates a new instance of CountThread */ W'lqNOX[v
public CountControl() {} * QgKo$IF
public synchronized void executeUpdate(){ P15
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Connection conn=null; CD|[PkjW
PreparedStatement ps=null; }r:o8+4
try{ T<AT&4
conn = DBUtils.getConnection(); 4fEDg{T
conn.setAutoCommit(false); !IxO''4
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); S{@}ECla
for(int i=0;i<CountCache.list.size();i++){ zkQ[<
CountBean cb=(CountBean)CountCache.list.getFirst(); C*7/iRe
CountCache.list.removeFirst(); {z#2gc'Q
ps.setInt(1, cb.getCountId()); GIC1]y-'
ps.executeUpdate();⑴ "}4%v Zz
//ps.addBatch();⑵ \8`?ir
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} <xOv8IQ|
//int [] counts = ps.executeBatch();⑶ wQkM:=t5
conn.commit(); /ZLY@&M
}catch(Exception e){ xO~ElzGm
e.printStackTrace(); / HTY>b
} finally{ GD
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try{ gYpMwC{*d
if(ps!=null) { Ui{%q@
ps.clearParameters(); $pGT1oF[E
ps.close();
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ps=null; :2 ;Jo^6Se
} KyvZ?R
}catch(SQLException e){} Tb/TP3N
DBUtils.closeConnection(conn); M>8J_{r^
} I[\~pi,
} UM}u(;oo%)
public long getLast(){ eI
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return lastExecuteTime; APQq F/
} =OVDJ0ozZ
public void run(){ 8)i""OD@I
long now = System.currentTimeMillis(); sV^:u^
if ((now - lastExecuteTime) > executeSep) { o5<<vvdA
//System.out.print("lastExecuteTime:"+lastExecuteTime); VJh8`PVX
//System.out.print(" now:"+now+"\n"); SC{m@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1J@Iekat
lastExecuteTime=now; vqf$("
executeUpdate(); <Au2e
} iCt.rr~;V
else{ ZzT=m*tQ&
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); niVR!l
} !xM5
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} KWTV!Wxb=K
} 5=dL`
//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 B@,9Cx564
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类写好了,下面是在JSP中如下调用。 K|& f5w
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<% /r}L_wI
CountBean cb=new CountBean(); wBPo{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ITu19WG
CountCache.add(cb); )8Va%{j
out.print(CountCache.list.size()+"<br>"); 9
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CountControl c=new CountControl(); }x8!{Y#cF
c.run(); xo:kT )
out.print(CountCache.list.size()+"<br>"); hy;VvAH5
%>