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: V8C62X
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CountBean.java FZk=-.Hk
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/* h?8I`Z)h
* CountData.java &d%0[Ui`
* ' F,.y6QU
* Created on 2007年1月1日, 下午4:44 E]aQK.
* ?3duW$`
* To change this template, choose Tools | Options and locate the template under X&bz%I>v
* the Source Creation and Management node. Right-click the template and choose XCN^>ToD
* Open. You can then make changes to the template in the Source Editor. {E 'go]
*/ =%i~HDiy
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package com.tot.count; uV|%idC
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/** N I*x):bx
* #;+ABV
* @author 'joc8o sS
*/ ><HHO
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public class CountBean { ]%Db %A
private String countType; u/ Gk>F
int countId; ,f[`C-\Q%
/** Creates a new instance of CountData */ *WQl#JAr
public CountBean() {} pXE'5IIN
public void setCountType(String countTypes){ .Fl5b}C(
this.countType=countTypes; KAFx^JLo
} cns~)j~
public void setCountId(int countIds){ *7JsmN?
this.countId=countIds; LQo>wl
} n N_Ylw
public String getCountType(){ ^&|KuI+u
return countType; A8zh27[w%
} 1y{@fg~..
public int getCountId(){ 32S5Ai@Cd"
return countId; GV"X) tGo
} `pJWZ:3
} ( +x!wX( x
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CountCache.java A`I ;m0<
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/* vNn$dc
* CountCache.java QcN$TxU >
* }rKKIF^f\S
* Created on 2007年1月1日, 下午5:01 M&h`uO/[
* uO{'eT~
* To change this template, choose Tools | Options and locate the template under r.vezsH
* the Source Creation and Management node. Right-click the template and choose ?3t]9z
* Open. You can then make changes to the template in the Source Editor. },& =r= B
*/ )zMsKfQ
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package com.tot.count; W*!u_]K>
import java.util.*; `9vCl@"IV
/** }|-Yd"$
* ][[\!og
* @author -udKGrT+
*/
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public class CountCache { #*v:.0%
public static LinkedList list=new LinkedList(); bmd3fJb`r
/** Creates a new instance of CountCache */ h;RKF\U:"
public CountCache() {} `U6bI`l
public static void add(CountBean cb){ a(|,KWHn
if(cb!=null){ ^1jZwP;5eW
list.add(cb); vbMt}bM(GD
} O@)D%*;v
} JXNfE,_
} v0uA]6:
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CountControl.java hL(zVkYI
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/* slRD /
* CountThread.java w.0:#4
* QBwgI>zfS"
* Created on 2007年1月1日, 下午4:57 =zXA0%
* -A3>+G3[
* To change this template, choose Tools | Options and locate the template under meM61ue_2
* the Source Creation and Management node. Right-click the template and choose sncc DuS
* Open. You can then make changes to the template in the Source Editor. |.;LI=CT
*/ uHu (
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package com.tot.count; f !D~aJ
import tot.db.DBUtils; ry[NR$L/m
import java.sql.*; oHvVZ
/** D8r=Vf
* %$3)xtS6
* @author D@
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*/ ^a?H"
public class CountControl{ *5Aq\g,n
private static long lastExecuteTime=0;//上次更新时间 DAHQ7#qfQC
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Q?7:XbN
/** Creates a new instance of CountThread */ 6d%'>^`(o-
public CountControl() {} LI/;`Y=
public synchronized void executeUpdate(){ Ljq!\D
Connection conn=null; 0{'%j~"
PreparedStatement ps=null; [7|j:!
try{ Rb=8(#
conn = DBUtils.getConnection(); *LZ^0c: r
conn.setAutoCommit(false); *]]C.t-cd
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =3=
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for(int i=0;i<CountCache.list.size();i++){ :4'Fq;%C
CountBean cb=(CountBean)CountCache.list.getFirst(); -|\SNbPTV
CountCache.list.removeFirst(); Ei&
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ps.setInt(1, cb.getCountId()); @w]z"UCwV@
ps.executeUpdate();⑴ N-9qNLSP
//ps.addBatch();⑵ X1GpLy)p
} V {H/>>k7
//int [] counts = ps.executeBatch();⑶ BMlu>,
conn.commit(); 1;$8=j2
}catch(Exception e){ xO nW~Z
e.printStackTrace(); fj,]dQT
} finally{ e9e7_QG_-
try{ sKU?"|G81G
if(ps!=null) { |4tnG&=
ps.clearParameters(); ctB(c`zcY
ps.close(); 3Q-[)Z )
ps=null; Tl2e?El;4
}
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x`|!
}catch(SQLException e){} ! !9l@
DBUtils.closeConnection(conn); nL[zXl
} yxpDQO~x
} vxrRkOU1
public long getLast(){ ./!6M
return lastExecuteTime; pHpHvSI
} >*"6zR2 o
public void run(){ u|'}a3
long now = System.currentTimeMillis(); pPX ~pPIj2
if ((now - lastExecuteTime) > executeSep) { lx vRF93a.
//System.out.print("lastExecuteTime:"+lastExecuteTime); "Nx3_mQ
//System.out.print(" now:"+now+"\n"); NX5A{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [=xJh?*P
lastExecuteTime=now; G',*"mZQ[
executeUpdate(); )f6:{ma
} V&>\U?q:
else{ !^/Mn
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); k5=VH5{S
} 4\6-sL?rW
} sivd@7r\Fa
} 3n=`SLj/a
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 %j=xL V\
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类写好了,下面是在JSP中如下调用。 s, 8a1o
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<% [v!TQwMU
CountBean cb=new CountBean(); Y^(Sc4 W
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =CE(M},d
CountCache.add(cb); u?>]C6$
out.print(CountCache.list.size()+"<br>"); |=Mn~`9p
CountControl c=new CountControl(); 5"]t{-PD
c.run(); +C(v4@=nd
out.print(CountCache.list.size()+"<br>"); JrkjfoN
%>