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: t\ewHZG"
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CountBean.java )53y
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/* 8)I^ t81
* CountData.java (dSL7nel;L
* @f_+=}|dc
* Created on 2007年1月1日, 下午4:44 [!OxZ!
* |ZBI *
* To change this template, choose Tools | Options and locate the template under #Mw8^FST
* the Source Creation and Management node. Right-click the template and choose #>+ HlT
* Open. You can then make changes to the template in the Source Editor. Y:a]00&)#Y
*/ H7:] ]j1
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package com.tot.count; ]z9=}=If
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/** ?6Y?a2 |
* D}/vLw :v
* @author a:6m7U)P#5
*/ Tnm.A?
public class CountBean { M =r)I~
private String countType; 5XBH$&Td
int countId; Ph>%7M%
/** Creates a new instance of CountData */ +srGN5!
public CountBean() {} ')3
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public void setCountType(String countTypes){ gB'6`'
this.countType=countTypes; Q'0d~6n&{
} 6NHX2Ja
public void setCountId(int countIds){ &.?'i1!
this.countId=countIds; n.(FQx.F
} @MCg%Afw
public String getCountType(){ g}',(tPMZ
return countType; K(Bf2Mfq
} tZG:Pr1U@
public int getCountId(){ z' >_Mc6
return countId; n6a`;0f[R
} HC,Se.VYS
} [IhYh<i
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CountCache.java CizX<Cr}
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/* Jz e:[MYS
* CountCache.java JFk
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* 9-*uPK]m9
* Created on 2007年1月1日, 下午5:01 omBoo5e
* BR yl4
* To change this template, choose Tools | Options and locate the template under }U"&8%PZr
* the Source Creation and Management node. Right-click the template and choose W:L
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* Open. You can then make changes to the template in the Source Editor. WI-1)1t
*/ yaH
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package com.tot.count; rh}J3S5vp
import java.util.*; gSQJJxZ{?
/** ikiypWq
* >V}#[ /n
* @author v^ VitLC
*/ :G%61x&=Zc
public class CountCache { $ gS>FJ
public static LinkedList list=new LinkedList(); }Kbb4]t|"
/** Creates a new instance of CountCache */ E09:E
public CountCache() {} v
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public static void add(CountBean cb){ | h#u^v3
if(cb!=null){ ^3L0w}#
list.add(cb);
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} |_@>*Vmg
} IB]l1<
} j+
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CountControl.java b}TS0+TF
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/* Dwfu.ZJa
* CountThread.java P\rg"
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* YglmX"fLf
* Created on 2007年1月1日, 下午4:57 y/ef>ZZ
* dVT$ VQg
* To change this template, choose Tools | Options and locate the template under @QP z#-
* the Source Creation and Management node. Right-click the template and choose M:B=\&.O
* Open. You can then make changes to the template in the Source Editor. 338k?nHxv
*/ n8ZZ#}Nhg
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package com.tot.count; _.Uh)-yR
import tot.db.DBUtils; %aVq+kC h
import java.sql.*; x-&@wMqkc
/** |H+UOEiv,p
* 8NAON5.!
* @author PBTnIU
*/ CN8Y\<Ar
public class CountControl{ *mvlb
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private static long lastExecuteTime=0;//上次更新时间 t=W}SH
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 mSl.mi(JiZ
/** Creates a new instance of CountThread */ Trz@~d/[,n
public CountControl() {} ok\vQs(a
public synchronized void executeUpdate(){ Q:d]imw!O
Connection conn=null; 0[?Xxk}s0
PreparedStatement ps=null; ?QdWrE_
try{ aQ\$A`?
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); [~c|mOk
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); a'yK~;+_9
for(int i=0;i<CountCache.list.size();i++){ SbrecZ
CountBean cb=(CountBean)CountCache.list.getFirst(); )W
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CountCache.list.removeFirst(); 3K0A)W/YEs
ps.setInt(1, cb.getCountId()); o9yJf#-En
ps.executeUpdate();⑴ dn$!&
//ps.addBatch();⑵ w-L=LWL\
} PmEsN&YP]
//int [] counts = ps.executeBatch();⑶ 3kp+<$
conn.commit(); 6)
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}catch(Exception e){ XrGglBIV
e.printStackTrace(); V#gK$uv
} finally{ gu.}M:u
try{ eiaFaYe\
if(ps!=null) { XW)lDiJl
ps.clearParameters(); hH8oyIC
ps.close(); <
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ps=null; ['tY4$L(
} 4*cEag
}catch(SQLException e){} w;:*P
DBUtils.closeConnection(conn); ,G?WAOy,
} lE(HFal0-(
} /dI&o,sA
public long getLast(){ YWO)HsjP
return lastExecuteTime; bI9~jWgGp
} ~H<6gN<j(.
public void run(){ yg=q;Z>[~
long now = System.currentTimeMillis(); ~[nSXnPO
if ((now - lastExecuteTime) > executeSep) { hT&Y#fh
//System.out.print("lastExecuteTime:"+lastExecuteTime); >rmqBDKaQ
//System.out.print(" now:"+now+"\n"); ZI}F om<
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Q1I6$8:7
lastExecuteTime=now; ]dmrkZz:
executeUpdate(); &d?CCb$|0Y
} }?_?V&K|
else{ 4-y:/8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); By",rD- r
} :v&$o'Sak
} SBk4_J/_
} u$Jz~:=,
//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 .|>3k'<l
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类写好了,下面是在JSP中如下调用。 )e=D(qd
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<% cj|80$cSA
CountBean cb=new CountBean(); U-(01-
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $$;M^WV^?.
CountCache.add(cb); s.QwSbw-g
out.print(CountCache.list.size()+"<br>"); d_E/8R_$L
CountControl c=new CountControl(); rCbDu&k]
c.run(); SaAFz&WRl
out.print(CountCache.list.size()+"<br>"); Q}K"24`=
%>