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: zFy0SzF
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CountBean.java XY[uyR4Z
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/* >a@c5
* CountData.java 9oly=&lJ
* <q
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* Created on 2007年1月1日, 下午4:44 28KS*5S
* a=<l}`*
* To change this template, choose Tools | Options and locate the template under Le&SN7I
* the Source Creation and Management node. Right-click the template and choose c~B[<.Qj
* Open. You can then make changes to the template in the Source Editor. <1HbjRw
*/ nu1s
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package com.tot.count; R^`# xQ
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/** ZGUhje!
* \/3Xb
* @author VP|ga}(
*/ EkV
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public class CountBean { WD=#. $z$
private String countType; aKkG[qN
int countId; >4gGb)
/** Creates a new instance of CountData */ CNCWxu
public CountBean() {} Cv@ZzILyoK
public void setCountType(String countTypes){ eIEr\X4\~~
this.countType=countTypes; F;Q8^C0e*c
} tta\.ic
public void setCountId(int countIds){ O1+2Z\F
this.countId=countIds; c#?JW:^|Df
} j'#Y$d1.
public String getCountType(){ LTGKs^i4
return countType; :zXkQQD8`
} v(+9&
public int getCountId(){ 1l$c*STK
return countId; ;++CMTza]
} 5&WYL
} Ccmo(W+0
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CountCache.java C]ev"Am_)
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/* y\]~S2}G
* CountCache.java "0JG96&\
* wAC*D=Qj
* Created on 2007年1月1日, 下午5:01 bLrC_
* 2f'3Vjp~G
* To change this template, choose Tools | Options and locate the template under iElE-g@Ws
* the Source Creation and Management node. Right-click the template and choose #7!P3j
* Open. You can then make changes to the template in the Source Editor. ?lg
*/ w)A@
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package com.tot.count; |5o0N8!b[
import java.util.*; ZT>?[`Vgc
/** GCn^+`.h1t
* `:hEc<_/
* @author 1]wx Ru
*/ ?!R
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public class CountCache { C5Fk>[fS
public static LinkedList list=new LinkedList(); }bQqln)#
/** Creates a new instance of CountCache */ ku=o$I8K
public CountCache() {} J7FCW^-`3
public static void add(CountBean cb){ B3Id}[V
if(cb!=null){ Xr54/.{&@
list.add(cb); fAHK<G4
} f>LwsP
} '~2S BX?J
} 02U5N(s
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CountControl.java dd+[FU
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/* 95Q{d'&
* CountThread.java da c?b(
* [D[&aA
* Created on 2007年1月1日, 下午4:57 qDR`)hle
* Ba=P
* To change this template, choose Tools | Options and locate the template under `mN*"1p-
* the Source Creation and Management node. Right-click the template and choose =|lw~CW
* Open. You can then make changes to the template in the Source Editor. |P{K\;-
*/ A^/$ |@
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package com.tot.count; Vo@[
import tot.db.DBUtils; 9,h'cf`F
import java.sql.*; 8Vcg30_+
/** 'Xl[ y
* ?W l=F/
* @author >"^H"K/T
*/ %kM|Hk3d
public class CountControl{ [i7Ug.Oi"
private static long lastExecuteTime=0;//上次更新时间 L
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 J&%d(EJM
/** Creates a new instance of CountThread */ U%2[,c_
public CountControl() {} K OZHz`1!
public synchronized void executeUpdate(){ {fi:]|<1h
Connection conn=null; W'f{u&<
PreparedStatement ps=null; Ey5E1$w%&
try{ ! }u'%
conn = DBUtils.getConnection(); crV2T
conn.setAutoCommit(false); r^<W$-#
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ?k$3( -
for(int i=0;i<CountCache.list.size();i++){ PCxv_Svf
CountBean cb=(CountBean)CountCache.list.getFirst(); iqCZIahf
CountCache.list.removeFirst(); <t9#~x#'b
ps.setInt(1, cb.getCountId()); %_*q'6K
ps.executeUpdate();⑴ B^W0Ik`m
//ps.addBatch();⑵ 3GkVMYI
} |Gc2w]\3
//int [] counts = ps.executeBatch();⑶ _1D'9!+
conn.commit(); p=T,JAI t
}catch(Exception e){ Ol8ma`}Nq3
e.printStackTrace(); "xS?#^a
} finally{ m791w8Vr
try{ 9UD~$_<\
if(ps!=null) { SKx&t-
ps.clearParameters(); _7?LINF9
ps.close(); /UGH7srx
ps=null; Pb05>J3N
} fD8A+aA
}catch(SQLException e){} `mU'{
DBUtils.closeConnection(conn); [C@0&[[
} oM`[&m.,
} -5 -X[`cF
public long getLast(){ S`yY<1[O
return lastExecuteTime; N
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} ]YF[W`2h
public void run(){ aBX^Wd
long now = System.currentTimeMillis(); Y<X,(\iEHP
if ((now - lastExecuteTime) > executeSep) { y}NBJ
//System.out.print("lastExecuteTime:"+lastExecuteTime); O=wA/T=w?
//System.out.print(" now:"+now+"\n"); y993uP
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 16q"A$
lastExecuteTime=now; ]=5nC)|
executeUpdate();
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} -\mbrbG9H
else{ 3c<).aC0f
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Y|bCbaF
} )*[3Imq/
} ^MPl
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} Og8:
//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 h#K863
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类写好了,下面是在JSP中如下调用。 0)}bJ,5/
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<% Ip}(!D|
CountBean cb=new CountBean(); ]V!q"|
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ~`Q8)(y<#$
CountCache.add(cb); ^cO^3=
out.print(CountCache.list.size()+"<br>"); Q`#Y_N-h+
CountControl c=new CountControl(); <&3qFK*9r
c.run(); !|P>%bi
out.print(CountCache.list.size()+"<br>"); \wY? 6#;
%>