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: \]=''C=J
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CountBean.java ]5Mq^@mD'
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/* K*[`s'Ip-
* CountData.java Yfd0Np~
* }@H(z
* Created on 2007年1月1日, 下午4:44 "F+m}GJ=a
* Q^!x8oUF
* To change this template, choose Tools | Options and locate the template under 1HS43!
* the Source Creation and Management node. Right-click the template and choose @&xWd{8'
* Open. You can then make changes to the template in the Source Editor. [ qx[ 0
*/ WAqH*LB
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package com.tot.count; x^]J^L45
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/** 3F ]30
* qb1JE[2F
* @author s5cY>
*/ %;MM+xVVX
public class CountBean { NA;OT7X[
private String countType; SWWeN#Q
int countId; w1J%%//(h
/** Creates a new instance of CountData */ ~,O&A B
public CountBean() {} V+Y;
public void setCountType(String countTypes){ %-J}m
this.countType=countTypes; ;:A/WU.^
} 3s
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public void setCountId(int countIds){ .TpM3b#r
this.countId=countIds; /=IBK`
} jH~VjE>
public String getCountType(){ IJ E{JH
return countType; yYN _]&ag
} % db
public int getCountId(){ V3v/hV:
return countId; J-d>#'Wb|
} mP[Z lS~"
} /JbO $A
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CountCache.java Mv\]uAT`
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/* KzWqHq
* CountCache.java gO%oA} !i
* i8|0zI
* Created on 2007年1月1日, 下午5:01 bTep TWv
* _y5J]Yu`j
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. g?OC-zw
*/ 7+;CA+;
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package com.tot.count; o/4U`U)Q0v
import java.util.*; (t_%8Eu
/** |kK_B
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* 26B+qXEt
* @author 94Q?)0W$
*/ q)Qg'l^f
public class CountCache { *wp>a?sG\
public static LinkedList list=new LinkedList(); _Y _v&
/** Creates a new instance of CountCache */ q>f|1Pf
public CountCache() {} fq4[/%6,O
public static void add(CountBean cb){ JS2h/Y$
if(cb!=null){ Zt/4|&w
list.add(cb); HVH <S
} 7v]9) W=y
} S2<evs1d
} BBDt^$
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CountControl.java D&*'|}RZ
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/* Gc*p%2c
* CountThread.java |{V@t1`
* -F`uz,wZ
* Created on 2007年1月1日, 下午4:57 K.r
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* BRTCo,i
* To change this template, choose Tools | Options and locate the template under G/4~_\YMq
* the Source Creation and Management node. Right-click the template and choose D/&nEMp6
* Open. You can then make changes to the template in the Source Editor. T0v{qQ
*/ G7SmlFn?
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package com.tot.count; QA=mD^A
import tot.db.DBUtils; GD@|XwK){
import java.sql.*; RGe2N|
/** ,%d?gi"&
* R4g;-Ci->
* @author d:3OC&
*/ t
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public class CountControl{ .!Q*VTW
private static long lastExecuteTime=0;//上次更新时间 =g{Hs1W
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 y134m
/** Creates a new instance of CountThread */ yt[*4gF4
public CountControl() {} Xv2Q8-}w
public synchronized void executeUpdate(){ ;i-<dAV8B
Connection conn=null; 0dCg/wJx
PreparedStatement ps=null; p-f"4vH
try{ `EWQ>m+
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); %_.
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @FaK/lKK
for(int i=0;i<CountCache.list.size();i++){ s6(bTO.
CountBean cb=(CountBean)CountCache.list.getFirst(); `G "&IQ8.
CountCache.list.removeFirst(); 7u<C&Z/
ps.setInt(1, cb.getCountId()); P-?R\(QYtR
ps.executeUpdate();⑴ LXS)(-&
//ps.addBatch();⑵ T7LO}(I.&
} {66P-4Ev(
//int [] counts = ps.executeBatch();⑶ =`E{QCW
conn.commit(); Ft<B[bQ
}catch(Exception e){ VI k]`)#
e.printStackTrace(); ^SWV!rrg
} finally{ b*TQKYT
try{ i%n9RuULh
if(ps!=null) { |31/*J!@z*
ps.clearParameters(); UH`cWV Lpr
ps.close(); m8<.TCIQ
ps=null; %`\=qSf*
} Wa<SYJ
}catch(SQLException e){} Lk2;\ D>
DBUtils.closeConnection(conn); ,;)_$%bHc
} qQp;i{X
} bY}:!aR<mK
public long getLast(){ w`X0^<Fv
return lastExecuteTime; o:PdPuZVR
} "5@\"L
public void run(){ M,dp;
long now = System.currentTimeMillis(); g=e~YM85
if ((now - lastExecuteTime) > executeSep) { e'T|5I0K
//System.out.print("lastExecuteTime:"+lastExecuteTime); (d*~Qpi{7
//System.out.print(" now:"+now+"\n"); o}e]W,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &f-x+y
lastExecuteTime=now; X86r`}
executeUpdate(); ZZrvl4h
} zbAyYMtEk
else{ Mz: "p.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); S!8q>d,%L
} UTVqoCHA
} UO4z~
} #n.XOet<\
//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 )St`}qu;
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类写好了,下面是在JSP中如下调用。 5%]O'h
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<% |* B9{/;4
CountBean cb=new CountBean(); WSqo\]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .f9&.H#
CountCache.add(cb); j5!pS xOC
out.print(CountCache.list.size()+"<br>"); q$kx/6=k
CountControl c=new CountControl(); _18Aek
c.run(); A7R [~
out.print(CountCache.list.size()+"<br>"); PYyT#AcW2
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