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: ^J]_O_ee$
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CountBean.java $yoIz.?V
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/* *mVQN1
* CountData.java s^vw]D
* exP:lO_0n
* Created on 2007年1月1日, 下午4:44 4S7#B
* S
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* To change this template, choose Tools | Options and locate the template under azCod1aL{
* the Source Creation and Management node. Right-click the template and choose m|by^40A(
* Open. You can then make changes to the template in the Source Editor. pl4:>4l/
*/ Tu[I84
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package com.tot.count; bd$``(b`v
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/** x)0''}E~
* H'_ v
* @author CTP!{<ii
*/ -TT{4\%s
public class CountBean { YLU.]UC
private String countType; . l>.
int countId; %p}xW V .
/** Creates a new instance of CountData */ |!?lwBs4
public CountBean() {} ~:xR0dqx
public void setCountType(String countTypes){ `=.A])>
this.countType=countTypes; k>V~iA
} .Z9{\tj
public void setCountId(int countIds){ <t"KNKI
this.countId=countIds; .Y*jL &!
} 2E$K='H:,
public String getCountType(){ v1aE[Q
return countType; x1'4njTV$
} 4R&e5!
public int getCountId(){ dm~Uj
return countId; p?H2W-
} xWuvT, ^
} p\G1O*Z
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CountCache.java h~r&7G@[}
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/* (/^dyG|X'
* CountCache.java 3;<Vv*a"Dm
* I*`;1+`
* Created on 2007年1月1日, 下午5:01
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* %h9'kJzNk
* To change this template, choose Tools | Options and locate the template under t^|GcU]
* the Source Creation and Management node. Right-click the template and choose .:(T}\]R
* Open. You can then make changes to the template in the Source Editor. r=4vN=:
*/ *!c&[- g
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package com.tot.count; QTmMj@R&(
import java.util.*; zk^uS #
/** =}OcMM`f
* h}n?4B~Gi
* @author ["~T)d'
*/ +]$c+!khj
public class CountCache { <HXzcWQ$
public static LinkedList list=new LinkedList(); 4%"Df1U
/** Creates a new instance of CountCache */ + :;6kyM6X
public CountCache() {} kVY0
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public static void add(CountBean cb){ *Kmo1>^
if(cb!=null){ -Crm#Ib~
list.add(cb); `s|^
} ~(P\'H&(h
} &S9O:>=*
} pp1kcrE\M
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CountControl.java q!Q*T^-rO
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/* ]?*L"()kp
* CountThread.java ?atHZLF
* xO
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* Created on 2007年1月1日, 下午4:57 Prqr,
* | h%0)_
* To change this template, choose Tools | Options and locate the template under |576)
* the Source Creation and Management node. Right-click the template and choose ,UATT]>
* Open. You can then make changes to the template in the Source Editor. iNG =x
*/ %j.
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package com.tot.count; =j^wa')
import tot.db.DBUtils; rL23^}+^`
import java.sql.*; `-yiVUp1:z
/** W+'f|J=
* eQ80Kf~
* @author !vGJ7
*/ _M)J{ {?:
public class CountControl{ (3
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private static long lastExecuteTime=0;//上次更新时间 n,*E
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ^2-+MWW.
/** Creates a new instance of CountThread */ LLU]KZhtY|
public CountControl() {} HbMD5(
public synchronized void executeUpdate(){ <Url&Z
Connection conn=null; Jie=/:&
PreparedStatement ps=null; *f
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try{ 5fuYva
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conn = DBUtils.getConnection(); q!whWA
conn.setAutoCommit(false);
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); -oB`v'
for(int i=0;i<CountCache.list.size();i++){ a(IZ2Zmr
CountBean cb=(CountBean)CountCache.list.getFirst(); m.&"D>
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CountCache.list.removeFirst(); 2bt).gGm
ps.setInt(1, cb.getCountId()); Ox^VU2K;&.
ps.executeUpdate();⑴ _qU;`Q
//ps.addBatch();⑵ ~ea&1+Z[3
} jUCDf-_ m
//int [] counts = ps.executeBatch();⑶ evro]&N{
conn.commit(); iXD=_^^o .
}catch(Exception e){ VdE$ig@
e.printStackTrace(); M2piJ'T4u
} finally{ W&p f%?
try{ !+Zso&
if(ps!=null) { +1>\o|RF
ps.clearParameters(); 3fq'<5 ^
ps.close(); EE,C@d!*k7
ps=null; P%y$e0
} 6T-iBJT
}catch(SQLException e){} QB6.
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DBUtils.closeConnection(conn); 6(-c$d`C.0
} %Zi}sm1t
} 3&5AbIZ
public long getLast(){ [9,34/i
return lastExecuteTime; my*E7[
} N51WY7
public void run(){ YE[{Y(5;q
long now = System.currentTimeMillis(); 9YVr9BM'K
if ((now - lastExecuteTime) > executeSep) { 6UAw9
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//System.out.print("lastExecuteTime:"+lastExecuteTime); jM;?);Dd
//System.out.print(" now:"+now+"\n"); CQI\/oaO
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); o0#zk
lastExecuteTime=now; IIUTo
executeUpdate(); 7~2V5@{<
} 2O
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else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); gjc[\"0a5h
} =fcRH:B:
} 'tMS5d)4:
} 1)!?,O\ey
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 f (ug3(j
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类写好了,下面是在JSP中如下调用。 g]m}@b6(h
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<% ]6;oS-4gu?
CountBean cb=new CountBean(); E#/vgm=W;
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); I^!c1S
CountCache.add(cb); xG|n7w*
out.print(CountCache.list.size()+"<br>"); ^k4 n
CountControl c=new CountControl(); O+PRP"$g"
c.run(); ?RU_SCp-
out.print(CountCache.list.size()+"<br>"); ,Laz515
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