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: PI<vxjOK`
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CountBean.java nj4/#W
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/* 0CvUc>Pj`"
* CountData.java -{A<.a3P}=
* u= yOu^={
* Created on 2007年1月1日, 下午4:44 |cY`x(?yP
* GKCroyor
* To change this template, choose Tools | Options and locate the template under 2"~8Z(0
* the Source Creation and Management node. Right-click the template and choose :Qq#Z
* Open. You can then make changes to the template in the Source Editor. mA} "a<0
*/ -']56o_sQ/
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package com.tot.count; mVmGg,
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/** mBC+6(5V
* YbLW/E\T
* @author |nF 8gh~}
*/ L=h'Qgk%
public class CountBean { .sA.C]f
private String countType; <\FH fE
int countId; :H[6Lg\*
/** Creates a new instance of CountData */ r_.S>]
public CountBean() {} *$*ce|V5
public void setCountType(String countTypes){ Vz[C=_m
this.countType=countTypes; M:V_/@W.
} @|)Z"m7
public void setCountId(int countIds){ 8r!zBKq2~
this.countId=countIds; qY#6SO`_iy
} ~_ a-E
public String getCountType(){ 4/)k)gLI
return countType; Qci]i)s$js
} -{_PuJ "
public int getCountId(){ =":,.Ttq41
return countId; 3mni>*q7d
} Sx\]!B@DSu
} h.fq,em+H
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CountCache.java lys#G:H]
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/* BluVmM3Vj
* CountCache.java 9{uO1O\
* P
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* Created on 2007年1月1日, 下午5:01 $wU\Js`/S]
* u-C)v*#L
* To change this template, choose Tools | Options and locate the template under i@CxI<1'
* the Source Creation and Management node. Right-click the template and choose L.WljNo
* Open. You can then make changes to the template in the Source Editor. 39jG8zr=Z[
*/ W'.m'3#z
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package com.tot.count; Ca3~/KrM
import java.util.*; t0I{q0
/** ]:\dPw`A
* }d }lR
* @author 8.~kK<)!
*/ E~:x(5'%d
public class CountCache { jA/w|\d!
public static LinkedList list=new LinkedList(); D,ln)["xm
/** Creates a new instance of CountCache */ Q3SS/eNP
public CountCache() {} Y4(
public static void add(CountBean cb){ K4);HJ|=
if(cb!=null){ 8x{'@WCG%
list.add(cb); bYPK h
} 'Z |mQZN
} ctJE+1#PH
} 8sCv]|cn
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CountControl.java ]0\MmAJRn
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/* e0 T\tc
* CountThread.java A +)`ZTuO
* 2Wb]4-
* Created on 2007年1月1日, 下午4:57 F}qc0
* Hq 188<
* To change this template, choose Tools | Options and locate the template under K_-MYs.
* the Source Creation and Management node. Right-click the template and choose j8`BdKg
* Open. You can then make changes to the template in the Source Editor.
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*/ +2j AC r
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package com.tot.count; 40<mrVl
import tot.db.DBUtils; PiYxk+N
import java.sql.*; 6JQ'Ik;$wX
/** V$?SR44>nH
* 8&aq/4:q0
* @author J)C/u{o
*/ K96<M);:g
public class CountControl{ !0cD$^7
private static long lastExecuteTime=0;//上次更新时间 "-J-k=
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ?I@W:#>o
/** Creates a new instance of CountThread */ ,4oo=&
public CountControl() {} bY0|N[g
public synchronized void executeUpdate(){ o0vUj
Connection conn=null; N8FF3}>
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PreparedStatement ps=null; @|%2f@h
try{ #lW`{i
conn = DBUtils.getConnection(); Wiu"k%Qsh
conn.setAutoCommit(false); &JI8]JmU)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (J!+(H8
for(int i=0;i<CountCache.list.size();i++){ Z)aUt
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CountBean cb=(CountBean)CountCache.list.getFirst(); _f:W?$\ho
CountCache.list.removeFirst(); 3Ims6I]
ps.setInt(1, cb.getCountId()); >oe]$r
ps.executeUpdate();⑴ J9[r|`gJ(
//ps.addBatch();⑵ :[!j?)%>
} H'hpEwG
//int [] counts = ps.executeBatch();⑶ zI<<Q2
conn.commit(); 8pgEix/M5o
}catch(Exception e){ 'X2POay1
e.printStackTrace(); (*)hD(C5
} finally{ ox (%5c)b|
try{ Q)[C?obd v
if(ps!=null) { >
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ps.clearParameters(); J6aef^>
ps.close(); & 9 ?\b7
ps=null; [1
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} KyQX!,rV
}catch(SQLException e){} Hg$lXtn]
DBUtils.closeConnection(conn); w
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} 46&/gehr
} /d<P-!fK
public long getLast(){ ~La>?:g <+
return lastExecuteTime; EJNU761
} >s?S+W[L
public void run(){ :zF,A,)
long now = System.currentTimeMillis(); 'y3!fN=h
if ((now - lastExecuteTime) > executeSep) { .xWC{}7[
//System.out.print("lastExecuteTime:"+lastExecuteTime); OH(waKq2I
//System.out.print(" now:"+now+"\n"); +&2%+[nBZ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); %n: k#
lastExecuteTime=now; b`O'1r\Y;
executeUpdate(); q(2'\ _`u
} nK%LRcAs
else{ R[x_j
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [ ~&/s:Vvo
} ah+iZ}E%
} 5S--'=fu+
} X*@dj_,
//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 xx%j.zDI]
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类写好了,下面是在JSP中如下调用。 _8_R 1s
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<% ]F'e
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CountBean cb=new CountBean(); @7j AL -
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); v<(
CountCache.add(cb); "mvt>X
out.print(CountCache.list.size()+"<br>"); h|{]B,.Lh
CountControl c=new CountControl(); DG:Z=LuJr
c.run(); &AbNWtCV+G
out.print(CountCache.list.size()+"<br>"); *.d)OOpLo
%>