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: ;vbMC74J#
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CountBean.java _A0X[}^K
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/* Q("4R
* CountData.java /FC(d5I
* 2^w{Hcf
* Created on 2007年1月1日, 下午4:44 @2-;,VL3
* L]&y[/\E1
* To change this template, choose Tools | Options and locate the template under kLpq{GUv:
* the Source Creation and Management node. Right-click the template and choose j |o&T41
* Open. You can then make changes to the template in the Source Editor. c%(Ndi
*/ )r)ZmS5O
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package com.tot.count; 1?.NJ<)F
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/** cqW(9A|8
* 2"%f:?xV{
* @author L=M'QJl9
*/ bD|VT
public class CountBean { .b^!f<j
private String countType; BNFYUcVP
int countId; ]<c\+9
/** Creates a new instance of CountData */ $jv"$0Fc
public CountBean() {} 475g-t2"@
public void setCountType(String countTypes){ ^!n|j]aw
this.countType=countTypes; i
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} J+N
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public void setCountId(int countIds){ \C$cbI=;+
this.countId=countIds; G-;EB
} oL<5hN*D
public String getCountType(){ ?C
return countType; CVEo<Tz
} #uCfXJ-
public int getCountId(){ >g@@ yR,
return countId; -%{+\x2
} P97i<pB Y_
} AEElaq.B
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CountCache.java J(=y$8xje
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/* #uICHt3
* CountCache.java GZY:EHuz[
* GxC\Nj#
* Created on 2007年1月1日, 下午5:01 aH8]$e8_,\
* pr,1pqiAf
* To change this template, choose Tools | Options and locate the template under 2k&Voa
* the Source Creation and Management node. Right-click the template and choose \$F#bIjC
* Open. You can then make changes to the template in the Source Editor. =U8+1b
*/ hb)C"q=
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package com.tot.count; pZt>rv
import java.util.*; sr(nd35
/** %,aSD#l`f
* bMv[.Z@v(
* @author T\:*+W37
*/ Z/4bxO=m
public class CountCache { [6/8O
public static LinkedList list=new LinkedList(); kr!>rqN5
/** Creates a new instance of CountCache */ OIjG`~Rx
public CountCache() {} ld 1[Usaq
public static void add(CountBean cb){ 0(&RmR
if(cb!=null){ S?VKzVDB.S
list.add(cb); NdXC8
} G{Uqp'=G
} UDnCHGq
} =5YbK1Q^
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CountControl.java jyidNPLm4
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/* &4l!2
* CountThread.java QA)W( 1
* Lc "{ePFh
* Created on 2007年1月1日, 下午4:57 #cb9g
* >enP~uW[#
* To change this template, choose Tools | Options and locate the template under Ea0EG>Y
* the Source Creation and Management node. Right-click the template and choose /BhP`a%2Q
* Open. You can then make changes to the template in the Source Editor. 7_lgo6
*/ Fx)><+-
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package com.tot.count; =2vZqGO30
import tot.db.DBUtils; yD8Qy+6L
import java.sql.*; h53G$Ol.
/** :R$v7{1
* #$!^1yO
* @author *e<'|Kq
*/ m"AyO"}I5
public class CountControl{ 2^U?Ztth6
private static long lastExecuteTime=0;//上次更新时间 vy>(?[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 r]wy-GT
/** Creates a new instance of CountThread */ U<'z,Px6
public CountControl() {} <xH!
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public synchronized void executeUpdate(){ [?g}<fa
Connection conn=null; vSH-hAk
PreparedStatement ps=null; (dV7N
try{ ma"M? aM
conn = DBUtils.getConnection(); %Rk0sfLvn
conn.setAutoCommit(false); oB'5':
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); c]ga)A(
for(int i=0;i<CountCache.list.size();i++){ i=fhK~Jd
CountBean cb=(CountBean)CountCache.list.getFirst(); vH E:TQo4
CountCache.list.removeFirst(); Z hCjY
ps.setInt(1, cb.getCountId()); `;m0GU68
ps.executeUpdate();⑴ f&&Ao
//ps.addBatch();⑵ C?6q]k]r
} -:b<~S[
//int [] counts = ps.executeBatch();⑶ [:A">eYI
conn.commit(); 2{g&9
}catch(Exception e){ {WeRFiQ?-
e.printStackTrace(); jX t5.9 t
} finally{ \oP
try{ i9peQ61{
if(ps!=null) { +hlR
ps.clearParameters(); 4(,X.GVY/
ps.close(); R m2M
ps=null; hWX4 P
} gDX\ p>7
}catch(SQLException e){} >9<rc[
DBUtils.closeConnection(conn); XqcNFSo)
} Jr>Nc}!U
} ^{E_fQJX
public long getLast(){ f
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return lastExecuteTime; nGTqW/k[+s
} Fg2/rC:_
public void run(){ ;BHIss7
long now = System.currentTimeMillis(); \z.p [;'ir
if ((now - lastExecuteTime) > executeSep) { |I.5]r-EK
//System.out.print("lastExecuteTime:"+lastExecuteTime); GB6(WAmr
//System.out.print(" now:"+now+"\n"); +>%AG&Pc
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 'sk M$jr
lastExecuteTime=now; ;b_<5S
executeUpdate(); vgr5j
} \,I{*!hw
else{ a3He-76
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Q"oJhxS
} }MM:q R
} 1O90 ]c0
} fECmELd
//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 = mhg@N4
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类写好了,下面是在JSP中如下调用。 t
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<% 8PG&/"K
CountBean cb=new CountBean(); FGpV
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); J]Q-#g'Z
CountCache.add(cb); h?GE-F
out.print(CountCache.list.size()+"<br>"); P>|sCF
CountControl c=new CountControl(); ~k ]$J|}za
c.run(); 8,B#W#*{
out.print(CountCache.list.size()+"<br>"); G/KTF2wl7
%>