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: ut\9@>*J=Q
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CountBean.java &F.lo9JJ
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/* ~^5uOeTZ~
* CountData.java zcZr
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* n.A[Z
* Created on 2007年1月1日, 下午4:44 /VJ@`]jhDf
* `DA=';>Y
* To change this template, choose Tools | Options and locate the template under _t;w n7p
* the Source Creation and Management node. Right-click the template and choose M6X f}>
* Open. You can then make changes to the template in the Source Editor. WHpbQQX
*/ #K)HuT
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package com.tot.count; R
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dR=SW0Oa{
/** ,bH
* |
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* @author *i$+i
*/ Wq>j;\3b3
public class CountBean { mU\$piei
private String countType; r% B5@+{so
int countId; xMuy[)b
/** Creates a new instance of CountData */ ]}5jX^j
public CountBean() {} b?y1cxTT
public void setCountType(String countTypes){ c|O5Vp}
this.countType=countTypes; 3}T&|@*
} -nd6hx
public void setCountId(int countIds){ <N`rcKE%~P
this.countId=countIds; T%]:
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} 75v*&-
public String getCountType(){ RyM2CQg[
return countType; igo7F@_,
} wvh4AE5F|z
public int getCountId(){ ]mqB&{g
return countId; u>? VD%
} Y*AHwc<w`
} t(_XB|AKm
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CountCache.java ' Uc|[l]
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/* <$=8'$T81
* CountCache.java n1;V2k{uV
* {< wq }~
* Created on 2007年1月1日, 下午5:01 m3|,c[M1
* <QJmdcG
* To change this template, choose Tools | Options and locate the template under )8N/t6Q
* the Source Creation and Management node. Right-click the template and choose je{5iIr3/
* Open. You can then make changes to the template in the Source Editor. #pVk%5N
*/ mC93
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package com.tot.count; y-Ol1R3:c#
import java.util.*; hZJ Nh,,w
/** /3c1{%B\
* <w:fR|O
* @author C<7J5
*/ ! TRiFD
public class CountCache { %-SP
public static LinkedList list=new LinkedList(); ~&qe"0
/** Creates a new instance of CountCache */ I7Eg$J&
public CountCache() {} M1g|m|H7
public static void add(CountBean cb){ '"KK|]vJ
if(cb!=null){ U{_O=S u
list.add(cb); >H%8~ Oek
} #".{i+3E
} aY?}4Bx
} P$oa6`%l
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CountControl.java ^wHO!$
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/* q6D hypB
* CountThread.java onmO>q*
* \e?T9c6,
* Created on 2007年1月1日, 下午4:57 &\(YmY
* Uexb>|
* To change this template, choose Tools | Options and locate the template under Y/hay[6
* the Source Creation and Management node. Right-click the template and choose dGfWRqS]
* Open. You can then make changes to the template in the Source Editor. u9&p/qMx2
*/ i4-L!<bJ
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package com.tot.count; 0b|!S/*A3
import tot.db.DBUtils; WFdS#XfV
import java.sql.*; \:#b9t{B-
/** tDwXb>
* '-~86Q
* @author +pV3.VMH0
*/ H_2hr[
public class CountControl{ <zUmcZ
private static long lastExecuteTime=0;//上次更新时间 *X>rvAd3
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 [v&_MQ
/** Creates a new instance of CountThread */ *%8us~w5/
public CountControl() {} $C>EnNx
public synchronized void executeUpdate(){ N ;hq
Connection conn=null; @s[bRp`gd
PreparedStatement ps=null; XR&*g1
try{ V]8fn MH
conn = DBUtils.getConnection(); {P3,jY^
conn.setAutoCommit(false); h '}5"m
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); :G`_IB\
for(int i=0;i<CountCache.list.size();i++){ rm
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CountBean cb=(CountBean)CountCache.list.getFirst(); 1,mf]7k$
CountCache.list.removeFirst(); o60wB-y
ps.setInt(1, cb.getCountId()); [|>.iH X
ps.executeUpdate();⑴ msCAC*;,
//ps.addBatch();⑵ W=b5{
6
} '(Bs<)(H
//int [] counts = ps.executeBatch();⑶ ^aC[ZP:
conn.commit(); HC0puLt_
}catch(Exception e){ k~gQn:.Cx
e.printStackTrace(); b6i0_fOO
} finally{ E=B9FIx~<
try{ COT;KC6
n
if(ps!=null) { *?8Q:@:
ps.clearParameters(); b
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_
ps.close(); 4VooU [Ka(
ps=null; FD6|>G
} x=Ru@n K;
}catch(SQLException e){} 1TVTP2&Rd
DBUtils.closeConnection(conn); BAPi<U'D
} [DE8s[i-
} +:t1P V;l
public long getLast(){ HOw][}M_w
return lastExecuteTime; [Cs2H8=#
} }FK6o
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public void run(){ vZKo&jUk
long now = System.currentTimeMillis(); Jk~T.p?tF
if ((now - lastExecuteTime) > executeSep) { "pH+YqJ$
//System.out.print("lastExecuteTime:"+lastExecuteTime); eMF%!qUr
//System.out.print(" now:"+now+"\n"); `b2I)xC#
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ALG
#)$|
lastExecuteTime=now; }cP3i
executeUpdate(); +j<Nu)0iY
} g&za/F
else{ ;aF / <r
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,aN/``j=
} S*]IR"YL
} <O*q;&9
} !1l2KW<be
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 dfrq8n]
!!QMcx_C#/
类写好了,下面是在JSP中如下调用。 EmH{G
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<% hZFbiGQr\
CountBean cb=new CountBean(); !pN,,H6Y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); X3"V1@-i4$
CountCache.add(cb); mA4v 4z
out.print(CountCache.list.size()+"<br>"); 4j | vzyc
CountControl c=new CountControl(); lDH0bBmd0
c.run(); h!Ka\By8#
out.print(CountCache.list.size()+"<br>"); ve.4""\a
%>