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: %9
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CountBean.java iE EP~
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/* #iKPp0`K*
* CountData.java BOOb{kcg
* (|\%)vH-
* Created on 2007年1月1日, 下午4:44 C$0rl74Wi
* 2qdc$I&$
* To change this template, choose Tools | Options and locate the template under sYhHh$mwA
* the Source Creation and Management node. Right-click the template and choose GbC@ |
* Open. You can then make changes to the template in the Source Editor. BG6.,'~7o
*/ -5oYGLS$y3
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package com.tot.count; *knN?`(x
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/** kQ]4Bo
* 0&u=(;Dr\
* @author bY-koJo
*/ d"yJ0F
public class CountBean { 97[wz C,
private String countType; ?W_8X2(`
int countId; R;w$_1
/** Creates a new instance of CountData */ !1ZItJ74#
public CountBean() {} ^7uXpqQBr
public void setCountType(String countTypes){ Jkv!]C
this.countType=countTypes; :>}7^1I
} @SH[<c
public void setCountId(int countIds){ XuWX@cK
this.countId=countIds; .]H/u
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} %+nM4)h
public String getCountType(){ M]|]b-#
return countType; lVuBo&
} b<!' WpY-
public int getCountId(){ a@Vk(3Rx_
return countId; vz(=3C[
} g(auB/0s
} sSf;j,7V
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CountCache.java &.(iS
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/* CIui9XNU
* CountCache.java u -)ED
* fWPa1E@
* Created on 2007年1月1日, 下午5:01 *s#6e}
* mz Cd@<T,
* To change this template, choose Tools | Options and locate the template under );T&pm:C>
* the Source Creation and Management node. Right-click the template and choose )Z/$;7]#
* Open. You can then make changes to the template in the Source Editor. <"K2t
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*/ n=)LB&
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package com.tot.count; pP#D*hiP-g
import java.util.*; /Xj{]i3{
/** k( Ik+=u
* h oO847
* @author "@5qjLz]
*/ (-Q~@Q1
public class CountCache { ^I|i9MH
public static LinkedList list=new LinkedList(); W[k rq_c-
/** Creates a new instance of CountCache */ f[vm]1#
public CountCache() {} ]&; In,z
public static void add(CountBean cb){ TQ:h[6v
if(cb!=null){ 0i"2s}^+_
list.add(cb); {\`y)k 7
} ~3-"1E>Rgy
} /NjBC[P
} }
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CountControl.java m]*a;a'}#
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/* N
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* CountThread.java \D k >dE&I
* HL]J=Gh
* Created on 2007年1月1日, 下午4:57 ;
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* |'&$VzA
* To change this template, choose Tools | Options and locate the template under ,}khu
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. -T;^T1
*/ Q=>5@sZB
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package com.tot.count; YD@Z}NE
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import tot.db.DBUtils; {]U
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import java.sql.*; [3sZ=)G
/** "+4Jmf9
* 00'SceL=`
* @author vNs`UkA
*/ p;'.7_1
public class CountControl{ WUjRnzVM
private static long lastExecuteTime=0;//上次更新时间 }Xk_
xQVt{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Sk"hqF.2
/** Creates a new instance of CountThread */ tBfmjxv
public CountControl() {} "g)bNgGV}
public synchronized void executeUpdate(){ E%;$vj'2
Connection conn=null; !Yr9N4
PreparedStatement ps=null; n_rpT.[
try{ 1_Ks*7vuq
conn = DBUtils.getConnection(); /F9Dg<#a
conn.setAutoCommit(false); j!NXNuy:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); g\q4-
for(int i=0;i<CountCache.list.size();i++){ qBcbMa9m
CountBean cb=(CountBean)CountCache.list.getFirst(); YjnQ@IfIH
CountCache.list.removeFirst(); - f ^!R
ps.setInt(1, cb.getCountId()); (]\p'%A)
ps.executeUpdate();⑴ TQKcPVlE
//ps.addBatch();⑵ 63%V_B|
} %'i_iF8.
//int [] counts = ps.executeBatch();⑶ (3$DUvx7
conn.commit(); SrB>_0**
}catch(Exception e){ f8SO:ihXL
e.printStackTrace(); |c8\alw
} finally{ +c!HXX
try{ rM,f7hm[S*
if(ps!=null) { ^&C/,,U
ps.clearParameters(); AX%}ip[PC
ps.close(); ,52Lm=n
ps=null; x7<NaMK\
} Cse`MP
}catch(SQLException e){} ?>{u@tYL
DBUtils.closeConnection(conn); ]LZ#[xnM7
} R) :Xs .
} *k; bkd4x
public long getLast(){ <`"
return lastExecuteTime; z/h]Jos
} KM)f~^
public void run(){ NOwd'iU
long now = System.currentTimeMillis(); D!OY <?
if ((now - lastExecuteTime) > executeSep) { aem gGw<
//System.out.print("lastExecuteTime:"+lastExecuteTime); R`DzVBLl
//System.out.print(" now:"+now+"\n"); kr~n5WiAZ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^`iz%^
lastExecuteTime=now; R4VX*qkB
executeUpdate(); 5@r6'Z
} u-y?i`
else{ K> 4w
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); +ctU7
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} &L5
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} XEbVsw
} Al6%RFt
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 3u[8;1}7Q
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类写好了,下面是在JSP中如下调用。 LQr!0p.i"
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<% 6nE/8m
CountBean cb=new CountBean(); ?D2a"a$^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <XG]aYBR
CountCache.add(cb); 9 Xl#$d5
out.print(CountCache.list.size()+"<br>"); 0Fon`3(^\
CountControl c=new CountControl(); YLTg(*
c.run(); n.a2%,|v
out.print(CountCache.list.size()+"<br>"); H"^9g3U
%>