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: vyNxT* ,[K
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CountBean.java 5d Eh7XL
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/* Pr':51(
* CountData.java Q{s H3Y#l
* #xsE3Wj-X
* Created on 2007年1月1日, 下午4:44 wN_Vfb
* [M]
* To change this template, choose Tools | Options and locate the template under =upeRY@u5
* the Source Creation and Management node. Right-click the template and choose u^@f&BIG]:
* Open. You can then make changes to the template in the Source Editor. }eCw6
*/ H%qsjB^
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package com.tot.count; b|l:fT?&
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/** eBZXI)pPh
* .F98G/s
* @author u_w#gjiC
*/ 2Q/x@aT,h
public class CountBean { 2e+UM$
private String countType; SE@LYeC}dE
int countId; &47i"%
/** Creates a new instance of CountData */ /?uPEKr
public CountBean() {} 1F5XvQl
public void setCountType(String countTypes){ cM(:xv
this.countType=countTypes; OcR$zlgs[v
} %<\vGqsM
public void setCountId(int countIds){ mitHT :%r2
this.countId=countIds; 8g@<d^8@
} <GS^
public String getCountType(){ q(
return countType; 1-8mFIK
} dP9qSwTa
public int getCountId(){ b6c Bg
return countId; N]>=p.#j
} zGb|) A~,
} F+YZE[h%
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CountCache.java \j@OZ
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/* ,Xu-@br{
* CountCache.java xgwY@'GN
* b1(T4w6
* Created on 2007年1月1日, 下午5:01 >!eAM )
* ,`'Qi%O
* To change this template, choose Tools | Options and locate the template under @6Y?\Wx$w
* the Source Creation and Management node. Right-click the template and choose v [wb~uw\
* Open. You can then make changes to the template in the Source Editor. :}He\V
*/ 9P1OP Xv*p
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package com.tot.count; nHM~
import java.util.*; :(/~:^!
/** LdYB7T,
* v> LIvi|]
* @author h9t$Uz^N
*/ 2,DXc30I
public class CountCache { R{C(K(5/
public static LinkedList list=new LinkedList(); `l\7+0W
/** Creates a new instance of CountCache */ m(r,Acy6
public CountCache() {} ak7bJ~)X=
public static void add(CountBean cb){ hi_NOx
if(cb!=null){ [`ebM,W
list.add(cb); l.q&D< _
} vLv@&lMW
} kjTduZ/3"
} {DV_*5
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CountControl.java 5MroNr
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/* I:=S0&%)
* CountThread.java :tz#v`3o
* *z5.vtfu!
* Created on 2007年1月1日, 下午4:57 .<->C?#
* 4X!/hI=jq
* To change this template, choose Tools | Options and locate the template under 7BE>RE=)
* the Source Creation and Management node. Right-click the template and choose ux=w!y;}
* Open. You can then make changes to the template in the Source Editor. =mO vs
*/ 2i)^!c
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package com.tot.count; W,K;6TZhh
import tot.db.DBUtils; JgxtlYjl
import java.sql.*; \Z?9{J
/** R|6Cv3:
*
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* @author tZ]?^_Y1
*/ /
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public class CountControl{ 8V~k5#&Ow
private static long lastExecuteTime=0;//上次更新时间 Cz9xZA{[M
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4-l8,@9
/** Creates a new instance of CountThread */ $jjfC
public CountControl() {} p\ Q5,eg
public synchronized void executeUpdate(){ W/=.@JjI
Connection conn=null; G4Q[Th
PreparedStatement ps=null; &agWaf1%a
try{ `
)/vq-9
conn = DBUtils.getConnection(); pd:WEI
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conn.setAutoCommit(false); ts,ZvY]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); V><,UI=,n
for(int i=0;i<CountCache.list.size();i++){ RFi
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CountBean cb=(CountBean)CountCache.list.getFirst(); 4)S,3G
CountCache.list.removeFirst(); .UQzPnK
ps.setInt(1, cb.getCountId()); ;0Q4<F
ps.executeUpdate();⑴ DHyq^pJ
//ps.addBatch();⑵
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} S.mG?zbw
//int [] counts = ps.executeBatch();⑶ {AhthR%(1
conn.commit(); U'k*_g
}catch(Exception e){ pI1-cV,`
e.printStackTrace(); TtJH7
} finally{ T]^62(So
try{ Fe# 1
if(ps!=null) { &DS/v)]
ps.clearParameters(); g&^quZ"H
ps.close(); +G$4pt|=
ps=null; ]{sU&GqBLe
} 7!$Q;A
}catch(SQLException e){} WQx?[tW(U
DBUtils.closeConnection(conn); TtK[nP
} ~Zun&b)S
} 5-FQMXgThc
public long getLast(){ 2Sle#nw3
return lastExecuteTime; F3y9@dA]
} S50k>_a;
public void run(){ s,"]aew
long now = System.currentTimeMillis(); EB0TTJR?#
if ((now - lastExecuteTime) > executeSep) { ]RZ|u*l=x
//System.out.print("lastExecuteTime:"+lastExecuteTime); &9.C l;I
//System.out.print(" now:"+now+"\n"); Wjo[ENHM
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); vt/x
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lastExecuteTime=now; cb@?}(aFl
executeUpdate(); ](Xb_xMf
} %@<8<6&q
else{ fnpYT:%fG
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); EH-sZAv
} `jDTzhO~
} 5^}\4.eXo
} %p Ynnfr
//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 SU MrFd~
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类写好了,下面是在JSP中如下调用。 GiJ *Wp
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<% TeMHm?1^
CountBean cb=new CountBean(); b}2ED9HG\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); mbKZJ{|4s
CountCache.add(cb); S%$ }(
out.print(CountCache.list.size()+"<br>"); ^8]NxV@l
CountControl c=new CountControl(); )~&CvJ
c.run(); aacpM[{f
out.print(CountCache.list.size()+"<br>"); /RG:W0=K
%>