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: ;7id![KI4
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CountBean.java XILB>o.^3
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/* S6k
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* CountData.java .hBq1p
* G?:{9. (
* Created on 2007年1月1日, 下午4:44 Yt]tRqrh;T
* BMubN
* To change this template, choose Tools | Options and locate the template under ~%SmH[i
* the Source Creation and Management node. Right-click the template and choose RCXm</
* Open. You can then make changes to the template in the Source Editor. l;*/F`>c
*/ xvP=i/SO
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package com.tot.count; "Di27Rq
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/** M^q< qS>d
* Ttr)e:
* @author nz{
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*/ T:v.]0l~
public class CountBean { "I[a]T}/
private String countType; 9q
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int countId; @DiXe[kI
/** Creates a new instance of CountData */ J1i{n7f=@
public CountBean() {} t)#8r,9c
public void setCountType(String countTypes){ Gv
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this.countType=countTypes; xC3h m
} {1 VHz])I
public void setCountId(int countIds){ T1$fu(f
this.countId=countIds; BZS%p
} |l4tR
public String getCountType(){ xJG&vOf;?
return countType; -^1}J
} 8Zj=:;
public int getCountId(){ N>R\,n|I
return countId; 3.i$lp`t
} #?x!:i$-
} Ck:RlF[6C
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CountCache.java #&V7CYJ
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/* l ga%U~
* CountCache.java VI xGD#m
* l dd8'2
* Created on 2007年1月1日, 下午5:01 -cgLEl1 J
* #7 )&`
* To change this template, choose Tools | Options and locate the template under 6MCLm.L
* the Source Creation and Management node. Right-click the template and choose /{)}y
* Open. You can then make changes to the template in the Source Editor. 0bG[pp$[
*/ Dno]N
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package com.tot.count; 6?;U[eV
import java.util.*; %G'{G
/** csh@C
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* lN(|EI
* @author OD@k9I[
*/ U46qpb7
public class CountCache { 2 m"2>gX
public static LinkedList list=new LinkedList(); ;mT|0&o>#
/** Creates a new instance of CountCache */
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public CountCache() {} Z\lJE>1
public static void add(CountBean cb){ ,6J{-Iu
if(cb!=null){ CP]nk0
list.add(cb); 7 XNZEi9o
} /)%$xi
} ]_"c_QG
} X!aC6gujOH
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CountControl.java CpE LLA<
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/* ?-Qq\D^+
* CountThread.java `EXo =Dqc
* aru;yR
* Created on 2007年1月1日, 下午4:57 N8[ &1
* -dto46X
* To change this template, choose Tools | Options and locate the template under ;JuBybJb
* the Source Creation and Management node. Right-click the template and choose e/7rr~"|
* Open. You can then make changes to the template in the Source Editor. !:]/MpQ ?
*/ 0?$jC-@k:
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package com.tot.count; q`Rc \aWB%
import tot.db.DBUtils; ngt?9i;N
import java.sql.*; V}Ok>6(~
/** |e QwI&
* KgH_-REN
* @author 7Dt*++:
*/ o8B$6w:_
public class CountControl{ 'bQjJRq!
private static long lastExecuteTime=0;//上次更新时间 [PIh^DhK
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 h5o6G1ur
/** Creates a new instance of CountThread */ ~D0e\Q(A
public CountControl() {} 5!s7`w]8*0
public synchronized void executeUpdate(){ Al
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Connection conn=null; _:1s7EC
PreparedStatement ps=null;
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try{ gLss2i.r
conn = DBUtils.getConnection(); <"hq}B
conn.setAutoCommit(false); )KdEl9 o
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); al{}_1XoU
for(int i=0;i<CountCache.list.size();i++){ &cpqn2Z
CountBean cb=(CountBean)CountCache.list.getFirst(); L^FQ|?*
CountCache.list.removeFirst(); 20,}T)}Tm
ps.setInt(1, cb.getCountId()); <#ng"1J
ps.executeUpdate();⑴ V;LV),R?
//ps.addBatch();⑵ b Y2:g )
} ,k9xI<i
//int [] counts = ps.executeBatch();⑶ O>@ChQF
conn.commit();
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}catch(Exception e){ vNDf1B5z
e.printStackTrace(); D_Zt:tzO
} finally{ ,%T
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try{ 4[lym,8C
if(ps!=null) { Xk(p:^ R
ps.clearParameters(); YlC$L$%Zd.
ps.close(); :^En\YcU
ps=null; X()yhe_
} pwg\b
}catch(SQLException e){} ]<BT+6L
DBUtils.closeConnection(conn); 8b[<:{[YB
} grxlGS~Q
} sTu]C +A
public long getLast(){ -NPX;e$<
return lastExecuteTime; ="('
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} GK`U<.[c
public void run(){ Z [YSET
long now = System.currentTimeMillis(); Kgw,]E&7
if ((now - lastExecuteTime) > executeSep) { [gIvB<Uv
//System.out.print("lastExecuteTime:"+lastExecuteTime); AsfmH-4)
//System.out.print(" now:"+now+"\n"); ._[uSBR'
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Zs|m_O G
lastExecuteTime=now; STL+tLJ
executeUpdate(); GUps\:ss
} 7o7*g 7
else{ | /X+2K}3
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); C <d]0)
} n[gc`#7|{e
} Ez+8B|0P
} NydF'N_1
//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 no,b_0@N
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类写好了,下面是在JSP中如下调用。 X?$"dqA
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<% pS~=T}o
CountBean cb=new CountBean(); 2AXf'IOqE
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ':7gYP*v
CountCache.add(cb); Y~B-dx'V
out.print(CountCache.list.size()+"<br>"); d$HPpi1LL
CountControl c=new CountControl(); ATF>"Ux
c.run(); w\1K.j=>|N
out.print(CountCache.list.size()+"<br>"); lNo]]a+_
%>