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: &@=u+)^-{
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CountBean.java uPFRh~ (b
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/* dj3|f{kg{
* CountData.java ktN%!Mh\
* Er`TryN|}
* Created on 2007年1月1日, 下午4:44 )qbI{^_g
* ~@xT]D!BQ
* To change this template, choose Tools | Options and locate the template under e%pu.q\gK
* the Source Creation and Management node. Right-click the template and choose ~GSpl24W<
* Open. You can then make changes to the template in the Source Editor. )i&%cyZw
*/ '^hsH1
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package com.tot.count; g+igxC}2z
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/** V:(y*tFA
* kl| g
* @author =ntftSH
*/ ,cLH*@
public class CountBean { xne]Q(B>
private String countType; bk.*k~_
int countId; wc"9A~
/** Creates a new instance of CountData */ %yeu"
public CountBean() {} 8IeI0f"l)
public void setCountType(String countTypes){ `4_c0q)N4
this.countType=countTypes; 2v4W6R
} I<sfN'FpT
public void setCountId(int countIds){ gglf\)E;}E
this.countId=countIds; ;;M"hI3@
} l/[pEUYU
public String getCountType(){ 3eWJt\}?B
return countType; H*GlWgfG
} _wmI(+_
public int getCountId(){ emA.{cVr!
return countId; Vu=] O/ =P
} C1tb`
} 2R\+}
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CountCache.java @`6}`k
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/* w\Iqzpikr
* CountCache.java r5[4h'f
* 9976H\{
* Created on 2007年1月1日, 下午5:01 g@Ld"5$^2
* Gy9
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* To change this template, choose Tools | Options and locate the template under YKY2Cw
* the Source Creation and Management node. Right-click the template and choose ]W;:|/,c
* Open. You can then make changes to the template in the Source Editor. P8<hvMF
*/ f9a$$nb3`
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package com.tot.count; $2Q YxY9s
import java.util.*; w763zi{
/** XC2FF&B&
* S@Iw;V
* @author sDX/zF6t
*/ @`S.@^%7fO
public class CountCache { |kseKZ3
public static LinkedList list=new LinkedList(); =DC3a3&%
/** Creates a new instance of CountCache */ F 5U|9<
public CountCache() {} Y.NE^Vn0
public static void add(CountBean cb){ "W5rx8a
if(cb!=null){ e^8BV;+c
list.add(cb); n+rM"Gxz
} O@wK[(w^
} lm*g Gy1i
} s&VOwU
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CountControl.java $ser+Jt=
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/* eF5;[v
* CountThread.java vY_eDJ~'
* -?z\5z
* Created on 2007年1月1日, 下午4:57 #1gO?N(<=
* x[x(y{&~
* To change this template, choose Tools | Options and locate the template under *V DVC0R
* the Source Creation and Management node. Right-click the template and choose iD714+N(
* Open. You can then make changes to the template in the Source Editor. \<V)-eB
*/ 1'fb
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package com.tot.count; S/7l/DFb
import tot.db.DBUtils; V%51k{
import java.sql.*; SY T$3|a
/** vBoO'l9'M
* o(fy d)t
* @author +?AW>&68y
*/ `tVy_/3(9
public class CountControl{ P)hi||[
private static long lastExecuteTime=0;//上次更新时间 esI'"hVJ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 J@Yj\9U
/** Creates a new instance of CountThread */ R6P\T\~E
public CountControl() {} Dr+ Ps
public synchronized void executeUpdate(){ p+ Lv=e)0u
Connection conn=null; H+x#gK2l
PreparedStatement ps=null; z_n\5.
try{ T5e^J"
conn = DBUtils.getConnection(); 5v|EAjB6o
conn.setAutoCommit(false); tvpN/p
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 0OWL
for(int i=0;i<CountCache.list.size();i++){ -?fR|[\[U
CountBean cb=(CountBean)CountCache.list.getFirst(); &*gbK6JB
CountCache.list.removeFirst(); -Qb0:]sV#
ps.setInt(1, cb.getCountId()); !*vBW/
ps.executeUpdate();⑴ mb{q(WEPP
//ps.addBatch();⑵ B9#;- QO
} (Ilsk{aB;A
//int [] counts = ps.executeBatch();⑶ A[JM4x
conn.commit(); wW5Yw
i
}catch(Exception e){ y6%<zhs
e.printStackTrace(); ~Z/7pP+
} finally{ >nM%p4E
try{ vYnftJK&
if(ps!=null) { [W;[v<E;
ps.clearParameters(); 1;&T^Gdj
ps.close(); S(t{&+Wc
ps=null; GOVAb'
} XU9'Rfp
}catch(SQLException e){} 7' eh)[T
DBUtils.closeConnection(conn); [:B*6FXMN~
} WQKj]:qk0
} +)gB9DoK
public long getLast(){ {ERjeuDm]
return lastExecuteTime; vGN3 YcH
} =x
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public void run(){ "&-C$J5
Id
long now = System.currentTimeMillis(); TB#Nk5
if ((now - lastExecuteTime) > executeSep) { )`Ed_F}k
//System.out.print("lastExecuteTime:"+lastExecuteTime); H[nz]s
//System.out.print(" now:"+now+"\n"); jVYH;B%%z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); MGybGbd
lastExecuteTime=now; VQ<5%+
executeUpdate(); D9o*8h2$
} RIjM(P
else{ Euu
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ?v.Gn9Z&
} .Dx2 ;lj
} c<tmj{$
} x+^Vg3 q
//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 &t6Tcy
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类写好了,下面是在JSP中如下调用。 IG|\:Xz
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<% 7I3 :u+
CountBean cb=new CountBean(); ?Ib}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 3Gd|YRtk
CountCache.add(cb); =v0~[E4
out.print(CountCache.list.size()+"<br>"); 6~@5X}^<0
CountControl c=new CountControl(); yjpz_<7a=
c.run(); ,8VXA +'_
out.print(CountCache.list.size()+"<br>"); %?dE{ir
%>