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: 1o$<pZZ
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CountBean.java L'Wcb
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/* F4:ssy^
* CountData.java gmM79^CEF
* +XIN-8
* Created on 2007年1月1日, 下午4:44 `@:^(sMo
* 4+uAd"
* To change this template, choose Tools | Options and locate the template under ukPV nk
* the Source Creation and Management node. Right-click the template and choose zz$*upxK
* Open. You can then make changes to the template in the Source Editor.
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*/ \dCdyl6V
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package com.tot.count; x2nNkd0h
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/** AFY;;_Xks
* au#IA
* @author M9i u#6P
*/ Ml)WY#7
public class CountBean {
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private String countType; S[%86(,*gP
int countId; B,A/
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/** Creates a new instance of CountData */ ,iHl;3bu
public CountBean() {} LUCpZ3F1
public void setCountType(String countTypes){ /
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this.countType=countTypes; . Bv;Zv
} jgC/
public void setCountId(int countIds){ uEk$Y=p7!
this.countId=countIds; W"~G]a+
} rK`*v*
public String getCountType(){ Ddu$49{S:
return countType; kgA')]
} ++FMkeHZ
public int getCountId(){ 2B*9]AHny
return countId; JNsK
} u9?85
} 7o;}"Y1
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CountCache.java d_OHQpfK
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/* vZk+NS<
* CountCache.java Dn9Ta}miTO
* +p_SKk!%+
* Created on 2007年1月1日, 下午5:01 Q"\*JV5
* d F),
* To change this template, choose Tools | Options and locate the template under gB&'MA!
* the Source Creation and Management node. Right-click the template and choose ?6a:!^eL
* Open. You can then make changes to the template in the Source Editor. 6@nE cr
*/ F+}MW/ra@
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package com.tot.count; =>ignoeI
import java.util.*; NBLOcRSh
/** (h2bxfV~+
* TMq\}k-I5
* @author \N!k)6\
*/ *P9)M%
public class CountCache { F9Mv$g79
public static LinkedList list=new LinkedList(); 6Si z9
/** Creates a new instance of CountCache */ *)"`v]
public CountCache() {} (LGx;9S?
public static void add(CountBean cb){ "Z#&A
if(cb!=null){ Vw+U?
list.add(cb); )|*HkdF`
} QQ pe.oF
} {E>kFeg
} 3F<My+J
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CountControl.java 9.>v
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/* T?Hs_u{
* CountThread.java P1)9OE
* A5/Q:8b
* Created on 2007年1月1日, 下午4:57 $+
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* &;*jMu6
* To change this template, choose Tools | Options and locate the template under &i6WVNGy
* the Source Creation and Management node. Right-click the template and choose z0doLb^!
* Open. You can then make changes to the template in the Source Editor. Xul<,U~w6
*/ c"6<p5j!
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package com.tot.count; ~6E
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import tot.db.DBUtils; #_|6yo}
import java.sql.*; Bg Uf:PT
/** V"k*PLt
* ^ WidA-
* @author CH!Lf,G
*/ YY'46
public class CountControl{ b,~6cDU
private static long lastExecuteTime=0;//上次更新时间 = gOq
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ..;}EFw5
/** Creates a new instance of CountThread */ ub7|'+5
public CountControl() {} /+iU1m'(
public synchronized void executeUpdate(){ U z[#t1*
Connection conn=null; 4E<iIA\x
PreparedStatement ps=null; 6[w_/X"
try{ A6pPx1-&
conn = DBUtils.getConnection(); <4D.P2ct
conn.setAutoCommit(false); \"|E8A6/
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 0LeR#l:I
for(int i=0;i<CountCache.list.size();i++){ M qFuZg
CountBean cb=(CountBean)CountCache.list.getFirst(); IP9mv`[
CountCache.list.removeFirst(); hvwKhQ}wX
ps.setInt(1, cb.getCountId()); 7c5+8k3
ps.executeUpdate();⑴ jgK8} C
//ps.addBatch();⑵ .\".}4qQ
} 1T!(M"'Ij
//int [] counts = ps.executeBatch();⑶ tp7cc;0
conn.commit(); Am{Vtl)i
}catch(Exception e){ nj]l'~Y0
e.printStackTrace(); LJ\uRfs
} finally{ p gWBW9\
try{ {ZrIA+eH
if(ps!=null) { zU}Ru&T9
ps.clearParameters(); Pq KbG<}Y
ps.close(); V*Ta[)E
ps=null; U\s.fIr
} lhZXq!2p
}catch(SQLException e){} >;:235'(M
DBUtils.closeConnection(conn); 7A<X!a
} "**Tw'
} F-D9nI4{X
public long getLast(){ p.~hZ+ x_
return lastExecuteTime; RoS&oGYqR
} *6IytWOX5
public void run(){ Wl\.*^`k
long now = System.currentTimeMillis(); bbddbRj;
if ((now - lastExecuteTime) > executeSep) { 6QO[!^lY
//System.out.print("lastExecuteTime:"+lastExecuteTime); leR-oeSO
//System.out.print(" now:"+now+"\n"); ~
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); pMndyuoJl
lastExecuteTime=now; KxhMPvN'
executeUpdate(); +-"uJIwMD
} n
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else{ |KY6IGcqV
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8A'oK8Q
} QMwrt
} @komb IK
} __LR!F]=i
//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 (
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类写好了,下面是在JSP中如下调用。 L6<.>\^Z"
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<% FabgJu
CountBean cb=new CountBean(); {8p<iY- %
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); @$mh0K>
CountCache.add(cb); r9sq3z|%
out.print(CountCache.list.size()+"<br>"); V7DMn@Ckw
CountControl c=new CountControl(); =[5F~--Tf
c.run(); eO%w
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out.print(CountCache.list.size()+"<br>"); #$n >+lc
%>