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: !3Pmjip
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CountBean.java UF#!6"C@
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/* 9,`i[Dzp
* CountData.java rVoV@,P
* T>rmm7F
* Created on 2007年1月1日, 下午4:44 V@#oQi*
* PDuBf&/e
* To change this template, choose Tools | Options and locate the template under %
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* the Source Creation and Management node. Right-click the template and choose ~o"=4q`>
* Open. You can then make changes to the template in the Source Editor. 8{2
*/ o9"?z
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package com.tot.count; @=dv[P"jn
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/** 2(@2z[eKr
* xwof[BnEZ
* @author |`#fX(=
*/ E(|A"=\
public class CountBean { #5)/B
private String countType; #YE?&5t
int countId; I@/
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/** Creates a new instance of CountData */ A`f"<W-m
public CountBean() {} <;PKec
public void setCountType(String countTypes){ J*$%d1
this.countType=countTypes; $$1t4=Pz
} "}*D,[C5e
public void setCountId(int countIds){ |;wc8;
this.countId=countIds; gI;"P kN
} `7:uc@
public String getCountType(){ eQu(3 sYb
return countType; j0; ~2W#G*
} :1j8!R5
public int getCountId(){ Si?s69
return countId; /#M1J:SV
} CMW4Zqau*
} P7XZ|Td4*
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CountCache.java C:t>u..
#[{{&sN
/* &3Zb?
* CountCache.java rBTg"^jsw
* X_o#!
* Created on 2007年1月1日, 下午5:01 iv *$!\Cd
* %0C [v7\
* To change this template, choose Tools | Options and locate the template under .F 6US<]
* the Source Creation and Management node. Right-click the template and choose .k]`z>uv
* Open. You can then make changes to the template in the Source Editor. (is' ,4^b
*/ $ItmYj.m
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package com.tot.count; 3P2{M}WIl
import java.util.*; P|$n
/** 0@-4.IHl
* FDLo|aP/v
* @author [8sYE h
*/ KQNQ<OE4
public class CountCache { Ul_Zn
public static LinkedList list=new LinkedList(); Ol RXgJ
/** Creates a new instance of CountCache */ 4@{cK|
public CountCache() {} $lf/Mg_H
public static void add(CountBean cb){ t2(X
if(cb!=null){ Zpkd8@g@
list.add(cb); =eU=\td^
} Nt@|l7Xl*
} Za{O9Qc?D|
} 8c)GUx
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CountControl.java $45|^.b
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/* ]i.N'O<p
* CountThread.java \DQu!l@1U
* <
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* Created on 2007年1月1日, 下午4:57 1 Q(KZI
* l2St)`K8
* To change this template, choose Tools | Options and locate the template under Z&Ob,Ru
* the Source Creation and Management node. Right-click the template and choose A4,{ep'Z!
* Open. You can then make changes to the template in the Source Editor. *gwlW/%Fz
*/ ]{6/6jl
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package com.tot.count; wkx9@?2*
import tot.db.DBUtils; R QQ'Wg
import java.sql.*; D#&9zR86F
/** &>Ve4!i
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* Hh^ "c}
* @author \
T#|<=
*/ K`Kv .4
public class CountControl{ .8|wc
private static long lastExecuteTime=0;//上次更新时间 2~$S @c
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ),p0V
/** Creates a new instance of CountThread */ j J{F0o
public CountControl() {} LRu,_2"
public synchronized void executeUpdate(){ rH`\UZ{cc
Connection conn=null; prj(
PreparedStatement ps=null; 940:NOgm
try{ DH?n~qKpC
conn = DBUtils.getConnection(); i;1pw_K
conn.setAutoCommit(false); @FN|=?8%
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); /Yy)=~t{
for(int i=0;i<CountCache.list.size();i++){ p [C
9g
CountBean cb=(CountBean)CountCache.list.getFirst(); 5,gT|4|B\g
CountCache.list.removeFirst(); (& SU)Uvu
ps.setInt(1, cb.getCountId()); ~6t!)QATnp
ps.executeUpdate();⑴ W94:%
//ps.addBatch();⑵ %jjPs.
} -orRmn6}
//int [] counts = ps.executeBatch();⑶ %@vF%
conn.commit(); F9j@KC(yg
}catch(Exception e){ tC'E#2
e.printStackTrace(); =6dAF"b)
} finally{ NF8<9
try{ }?,?2U,8:
if(ps!=null) { Q^f{H.
ps.clearParameters(); ^5E9p@d"J
ps.close(); N4+Cg t(
ps=null; (SRY(q
} 2V)+ba|+
}catch(SQLException e){} g9" wX?*
DBUtils.closeConnection(conn); F9o7=5WAb
} / rc[HbNg.
} vWoppt
public long getLast(){ /*y5W-'d^
return lastExecuteTime; Q[#}Oh6$
} ?0t^7HMP
public void run(){ L=#NUNiXr
long now = System.currentTimeMillis(); rgVRF44X{
if ((now - lastExecuteTime) > executeSep) { P$U"y/
//System.out.print("lastExecuteTime:"+lastExecuteTime); H\QkU`b
//System.out.print(" now:"+now+"\n"); Qz[^J
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); /Ot3[B
lastExecuteTime=now; @G2# Z
executeUpdate(); ;-VZV p}Y
} r"2lcNE
else{ X=#us7W}
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); pZ>yBY?R8>
} [o<hQ`&
} v>wN
O
}
%!nI]|
//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 !vf:mMo
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类写好了,下面是在JSP中如下调用。 o9e8Oj&
T9V=#+8#"
<% Bn]=T
CountBean cb=new CountBean(); E_=F'sP?
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $97O7j@
CountCache.add(cb); T>asH
out.print(CountCache.list.size()+"<br>"); .1[.f}g$J
CountControl c=new CountControl(); 4 -tC=>>wc
c.run(); S&}7XjY
out.print(CountCache.list.size()+"<br>"); {d[Nc,AMb
%>