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: CDXN%~0h
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CountBean.java s]0 J'UN
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/* @ <2y+_e
* CountData.java 8 l)K3;q_
* JhwHsx/
* Created on 2007年1月1日, 下午4:44 V_D wHq2
* DTM(SN8R+n
* To change this template, choose Tools | Options and locate the template under Lk@+iHf
* the Source Creation and Management node. Right-click the template and choose frW\!r{LT
* Open. You can then make changes to the template in the Source Editor. :A!EjIL`#
*/ VS ;y
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package com.tot.count; m.`I}
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/** K5T1dBl,0
* X=Ar"Dx}}s
* @author DNqV]N_W
*/ $ta JVVF
public class CountBean { %e0X-tXcmX
private String countType; z;2& d<h
int countId; Y3FFi M[s~
/** Creates a new instance of CountData */ +;,J0,Yn
public CountBean() {} rr\9HA
public void setCountType(String countTypes){ #3LZX!
this.countType=countTypes; DO-M0L
} DNgh#!\X
public void setCountId(int countIds){ ("j;VqYUL
this.countId=countIds; n7~4*B
} E'D16Rhp
public String getCountType(){ &v1E)/q{Z
return countType; ?u:mscb
} Qjnh;uBO
public int getCountId(){ bpU>(j
return countId; oQV3
} @M-Q|
} yHC[8l8%
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CountCache.java LEtGrA/%@b
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/* btnD+O66<
* CountCache.java ,xrA2
* iHc(e(CB<
* Created on 2007年1月1日, 下午5:01 Fq <JxamR
* I ~YV&12
* To change this template, choose Tools | Options and locate the template under `uk=2k}&m
* the Source Creation and Management node. Right-click the template and choose GYb&'#F~t
* Open. You can then make changes to the template in the Source Editor. fK]%*i_"
*/ CMbID1M3
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package com.tot.count; _[(EsIqc(F
import java.util.*; Pw]r&)I`y[
/** nsXG@C S:
* z)v o
* @author LWhy5H;Es
*/ [*(1~PrlO,
public class CountCache { 4VeT]`C^h
public static LinkedList list=new LinkedList(); edcz%IOM(
/** Creates a new instance of CountCache */ D*VO;?D
public CountCache() {} ntPj9#lf
public static void add(CountBean cb){ o@dTiQK_
if(cb!=null){ J1cz
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list.add(cb); u*5}c7)uId
} 4|5;nxkGm8
} \4j_K*V
} 1i.3P$F
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CountControl.java 0m.`$nlV-
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/* +_*NY~
* CountThread.java F@Wi[K
* J@<f*
* Created on 2007年1月1日, 下午4:57 R<Mp$K^b
* [4YRyx&:++
* To change this template, choose Tools | Options and locate the template under Ah@e9`_r
* the Source Creation and Management node. Right-click the template and choose !ii(2U
* Open. You can then make changes to the template in the Source Editor. "+qZv(
*/ `^on`"\{u
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package com.tot.count; e:4,rfF1
import tot.db.DBUtils; Ei+lVLoC
import java.sql.*; 6(htpT%J
/** KVEc:<|x
* 9eP*N(m<
* @author aQY.96yo
*/ NRP)'E
public class CountControl{ yil5aUA
private static long lastExecuteTime=0;//上次更新时间 Gl3g.`X{$@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 TxN+-< f
/** Creates a new instance of CountThread */ f>cUdEPBb
public CountControl() {} O0BDUpH
public synchronized void executeUpdate(){ Q hRj*,
Connection conn=null; c w)J+Lyh
PreparedStatement ps=null; lWJYT<kt
try{ 9fTl6?x
conn = DBUtils.getConnection(); R8!~>$#C6)
conn.setAutoCommit(false); .8ikcs
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); [h' 22W
for(int i=0;i<CountCache.list.size();i++){ ;QCGl$8A
CountBean cb=(CountBean)CountCache.list.getFirst(); HpUJ_pZ
CountCache.list.removeFirst(); l<S3<'&
ps.setInt(1, cb.getCountId()); +"WNG
ps.executeUpdate();⑴ P92pQ_W
//ps.addBatch();⑵ i
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} }z\ t}lven
//int [] counts = ps.executeBatch();⑶ -H[@]Q4w
conn.commit(); g}hNsU=$5~
}catch(Exception e){ Pd d(1K*
e.printStackTrace(); Td7Q%7p:
} finally{ 7oUo [
try{ F/tRyq`D
if(ps!=null) { <j#IR
ps.clearParameters(); CV{ZoY
ps.close(); :U'n0\
ps=null; VB8eGMo
} &\6(iL
}catch(SQLException e){} SLN OOEN
DBUtils.closeConnection(conn); QL2LIs
} F`,bFQ
} e,#5I(E
public long getLast(){ HD$`ZV
return lastExecuteTime; A93(} V7I
} {LqYb:/C5U
public void run(){ tId,Q>zH
long now = System.currentTimeMillis(); lq`7$7-4
if ((now - lastExecuteTime) > executeSep) { |)O;+e\
//System.out.print("lastExecuteTime:"+lastExecuteTime); oHSDi
//System.out.print(" now:"+now+"\n"); MDd2B9cy[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !rqs!-cCQ
lastExecuteTime=now; fffWvf
executeUpdate(); Jzy:^PObT
} ab)ckRC
else{ *(i%\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0CX9tr2J
} AtAu$"ue
} YLSDJ$K6
} 6BQq|:U
//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 -,mV~y
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类写好了,下面是在JSP中如下调用。 t0:~BYXu
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<% Z%3)w.
CountBean cb=new CountBean(); L!ms{0rJ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); * "?,.
CountCache.add(cb); OMYbCy^
out.print(CountCache.list.size()+"<br>"); -I#<?=0B
CountControl c=new CountControl(); m,w^,)
c.run(); }>YEtA
out.print(CountCache.list.size()+"<br>"); ^QHgc_oDm
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