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: Ry;$^.7%
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CountBean.java }amU[U,
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/* U)jUq_LX
* CountData.java _]#klL
* =6nD0i9+
* Created on 2007年1月1日, 下午4:44 ^t.W|teD
* _"f :`
* To change this template, choose Tools | Options and locate the template under N$aZ== $5
* the Source Creation and Management node. Right-click the template and choose uF(k[[qaiN
* Open. You can then make changes to the template in the Source Editor. /9ZcM]X B
*/ 9G+f/k,P
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package com.tot.count; Z_z#QX>=D
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/** c,5n,i
* $N+6h#
* @author "X1vZwK8N
*/ *$,+`+
public class CountBean { i s"vekC
private String countType; "ORzWnE4U
int countId; V2znU
/** Creates a new instance of CountData */ Rq)BssdF
public CountBean() {} R"xp%:li
public void setCountType(String countTypes){ H3FW52pjX
this.countType=countTypes; Z[#IfbYt
} Ueyw;Y
public void setCountId(int countIds){ 83;IyvbL
this.countId=countIds; )qM|3],
} [,f)9v)
public String getCountType(){ |"k&fkS$
return countType; `7Ug/R<
} 1$LI px
public int getCountId(){ <!x+eE`
return countId; :X>DkRP
} tB6k|cPC
} hY;_/!_
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CountCache.java Lyoor1
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/* rg&+
* CountCache.java +uQB
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* |HbEk[?^s
* Created on 2007年1月1日, 下午5:01 av' *u
* rY70^<z
* To change this template, choose Tools | Options and locate the template under vZjZb(jlN
* the Source Creation and Management node. Right-click the template and choose : }?{@#Z
* Open. You can then make changes to the template in the Source Editor. %xg"Q|
*/ ?ApRJm:T
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package com.tot.count; F,}s$v
import java.util.*; gbGTG(:1S
/** |O (G nsZ
* Z;<ep@gy~
* @author k/`i6%F#m
*/ &hN,xpC
public class CountCache { (([I]q
public static LinkedList list=new LinkedList(); P^IY:
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/** Creates a new instance of CountCache */
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public CountCache() {}
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public static void add(CountBean cb){ rihlae5Kz
if(cb!=null){ {+=i?
list.add(cb); `SOhG?Zo
} rz6jx
} D VwCx^
} }iNY_I c
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CountControl.java FMS2.E
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/* 9*_uCPR
* CountThread.java 1%eLs=u?
* z\}!RBOq
* Created on 2007年1月1日, 下午4:57 {
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* _T~H[&Hl
* To change this template, choose Tools | Options and locate the template under ;nk@XFJ
* the Source Creation and Management node. Right-click the template and choose |~NeB"l{
* Open. You can then make changes to the template in the Source Editor. X<xqT
*/ 878tI3-
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package com.tot.count; {wu!6\:<??
import tot.db.DBUtils; 37>MJ
import java.sql.*; 3
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/** wo(j}O-
* k,]{NO
* @author !#.vyBK#
*/ L?f qcW{
public class CountControl{ 1URsHV!xcM
private static long lastExecuteTime=0;//上次更新时间 bOXh|u_3i
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ZjD2u8e
/** Creates a new instance of CountThread */ b\L)m (
public CountControl() {} %HEmi;
public synchronized void executeUpdate(){ `@$YlFOW
Connection conn=null; 9p<:LZd~
PreparedStatement ps=null; +{ab1))/
try{ z(UX't (q
conn = DBUtils.getConnection(); n4*'B*
conn.setAutoCommit(false); -A@U0=o
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); m|dF30~A
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); Fe4esg-B<
CountCache.list.removeFirst(); w4}(Ab<Y
ps.setInt(1, cb.getCountId()); >@Khm"/T
ps.executeUpdate();⑴ JS2!)aqc
//ps.addBatch();⑵ M,{<TpCx
} YHh u^}|jQ
//int [] counts = ps.executeBatch();⑶ oZvG3_H4.
conn.commit(); m/N(%oMWB=
}catch(Exception e){ 6SAQDE
e.printStackTrace(); L&HzN{K
} finally{ m?vAyi
try{ ^V,@=QL3U
if(ps!=null) { /O"0L/hc^
ps.clearParameters(); 2o}8W7y
ps.close(); }q x(z^
ps=null; :+A;TV
} 9jjL9f_3
}catch(SQLException e){} nK:`e9ES
DBUtils.closeConnection(conn); g{&PrE'e9
} \]GGVI;u
} "b;k.Fx
public long getLast(){ bgXc_>T6_y
return lastExecuteTime; 2 ^ kn5
} s.ey!ew
public void run(){ cFxSDTR
long now = System.currentTimeMillis(); [r~~=b7*[
if ((now - lastExecuteTime) > executeSep) { -9i+@%{/
//System.out.print("lastExecuteTime:"+lastExecuteTime); Ko}7$2^
//System.out.print(" now:"+now+"\n"); Nuo<` 6mV@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ~pwY6Q
lastExecuteTime=now; pb=HVjW<
executeUpdate(); 6KBHRt
} .=aMjrME
else{ @%7/2k
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X)FQ%(H<
} g&8 .A(
} ^)'||Ly
} ,DQ
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//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 ],#ZPUn
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类写好了,下面是在JSP中如下调用。 1r&AB!Z #
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<% l>33z_H^
CountBean cb=new CountBean(); ";58B}ki
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _"`/^L`Q?
CountCache.add(cb); w7[0
out.print(CountCache.list.size()+"<br>"); zkvH=wL
CountControl c=new CountControl(); gGD]t;<u
c.run(); [/n'@cjNZ
out.print(CountCache.list.size()+"<br>");
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%>