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: SiLWy=qbR
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CountBean.java *)bh6b=7
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/* 6qR5A+|;
* CountData.java GahIR9_2
* >1BDt:G36
* Created on 2007年1月1日, 下午4:44 bt=z6*C>A
* Rt.2]eZEJ
* To change this template, choose Tools | Options and locate the template under |\FJ
* the Source Creation and Management node. Right-click the template and choose \ORE;pG
* Open. You can then make changes to the template in the Source Editor. 6DVHJ+WTV
*/ ?G>E[!8ev
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package com.tot.count; B,b^_4XX$
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/** sW]>#e
* X"!tx
* @author EG!Nsb^,
*/ Ex<@:
public class CountBean { yYH>~,
private String countType; w!r.MWE
int countId; G?+0#?'Y
/** Creates a new instance of CountData */ ~P fk
public CountBean() {} tq=7HM
public void setCountType(String countTypes){ w&eq
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this.countType=countTypes; *4y0Hq
} {Q021*xt/
public void setCountId(int countIds){ bQ`2ll*(
this.countId=countIds; M~U>"kX
} 0ky3rFSh1
public String getCountType(){ }hA)p:
return countType; Lvb'qZ6n
} h'B0rVQia>
public int getCountId(){ Pd+Wb3
return countId; wBCBZs$H
} ^tL]QE?|
} Ri/D>[
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CountCache.java 9Xe|*bT
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/* uoq|l
* CountCache.java byHXRA)39
* Dco3`4pl
* Created on 2007年1月1日, 下午5:01 i4<n#]1!t
* !-Uq#Ea0/
* To change this template, choose Tools | Options and locate the template under \7WZFh%:
* the Source Creation and Management node. Right-click the template and choose _b!
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* Open. You can then make changes to the template in the Source Editor. ({<qs}H"
*/ | MXRNA~
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package com.tot.count; wV q4DE
import java.util.*; Y z],["*Q
/** %GigRA@no
* $r1{Nh
* @author 2OwO|n
*/ ow9Vj$m
public class CountCache { 0Wb3M"#9<
public static LinkedList list=new LinkedList(); YK V"bI
/** Creates a new instance of CountCache */ (m() r0:@
public CountCache() {} >mMmc!u>G
public static void add(CountBean cb){ V9;O1
if(cb!=null){ ;F:Qz^=.a
list.add(cb); ejpSbVJ
} rT'<6]`
} JqK-vvI
} Zr|\T7w 3
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CountControl.java 6'|NALW
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/* ub-vtRpm
* CountThread.java *#Iqz9X.Y3
* ug?#Oa
* Created on 2007年1月1日, 下午4:57 ^,#MfF6
* "|GX%>/
* To change this template, choose Tools | Options and locate the template under -:Jn|=
* the Source Creation and Management node. Right-click the template and choose ]m\:XhI*<
* Open. You can then make changes to the template in the Source Editor. S~ZRqL7ZO
*/ ?Lem|zo
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package com.tot.count; 2f2.;D5g_'
import tot.db.DBUtils; Q oWjC
import java.sql.*;
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/** d[&Ah~,
* i> PKE.
* @author }-PV%MNud
*/ $ItPUYi";
public class CountControl{ ^20x\K
private static long lastExecuteTime=0;//上次更新时间 +pjU4>)
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *}Gu'EU
/** Creates a new instance of CountThread */ aFDCVm%U|
public CountControl() {} h5ZxxtGU
public synchronized void executeUpdate(){ VMW<?V
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Connection conn=null; hQLh}}B
PreparedStatement ps=null; S %(R9N|
try{ JT*Pm"}
conn = DBUtils.getConnection(); wb6$R};?
conn.setAutoCommit(false); u\@L|rh
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); GI/4<J\
for(int i=0;i<CountCache.list.size();i++){ K@@Jt
CountBean cb=(CountBean)CountCache.list.getFirst(); 0hX@ta[Up
CountCache.list.removeFirst(); E akS(Q?
ps.setInt(1, cb.getCountId()); oT^r
ps.executeUpdate();⑴ 6gD|QC~;
//ps.addBatch();⑵ l`vr({A
} k6??+b:rE
//int [] counts = ps.executeBatch();⑶ 2"B3Q:0he|
conn.commit(); ?v Z5 ^k
}catch(Exception e){ n$jf($*
e.printStackTrace(); V2*m/JyeB
} finally{ Op
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try{ F>rf
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if(ps!=null) { &:Sb$+z
ps.clearParameters(); 23gJD8i8
ps.close(); #*;Nb
ps=null; l(?Yx
} EhHW`
}catch(SQLException e){} } bEu+bZ
DBUtils.closeConnection(conn); ?r}!d2:dX
} FUKE.Uxd
} u^uo=/
public long getLast(){ 6|{uZNz
return lastExecuteTime; d5tpw$A
} W'<cAg?
public void run(){ ?p!+s96
long now = System.currentTimeMillis(); KDy:A>_ G"
if ((now - lastExecuteTime) > executeSep) { W'M\DKJ?
//System.out.print("lastExecuteTime:"+lastExecuteTime); fSzX /r
//System.out.print(" now:"+now+"\n"); 21G:!t4/?n
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Y\ G^W8
lastExecuteTime=now; :@q9ll`6u
executeUpdate(); nwAx47>{
} T(6B,
else{ 8Zvh"Z?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); t+BLO<
} -g)*v<Fb5
} IP+1 :M
} 1@A*Jj[R%
//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 4r>buEU
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类写好了,下面是在JSP中如下调用。 m&Lc."
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<% c}g:vh
CountBean cb=new CountBean(); X5eTj
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); xn)r6
CountCache.add(cb); &_y+hV{
out.print(CountCache.list.size()+"<br>"); [EV}P&U
CountControl c=new CountControl(); N0G-/
c.run(); R7!^ M
out.print(CountCache.list.size()+"<br>"); ;t}ux
%>