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: hIHO a
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CountBean.java k.hSN8
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/* je0 ?iovY
* CountData.java 2 z l
* ~#xRoBy3
* Created on 2007年1月1日, 下午4:44 LD"}$vfs
* +w/o
* To change this template, choose Tools | Options and locate the template under p_N=V. w
* the Source Creation and Management node. Right-click the template and choose p#I1l2nE
* Open. You can then make changes to the template in the Source Editor. L3Iz]D3s
*/ 3<SC`6'?
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package com.tot.count; U%olH >1K
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/** |1x,_uyQ%
* w/@%xy
* @author iSax-Mc
*/ od|.E$B
public class CountBean { +d15a%^`
private String countType; e$h\7i:(
int countId; IT"jtV
/** Creates a new instance of CountData */ Tj#XsD?J
public CountBean() {} HyMb-Us
public void setCountType(String countTypes){ O2B$c\pw
this.countType=countTypes; 7u(i4O&
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} &ICO{#v5
public void setCountId(int countIds){ F!<x;h(
this.countId=countIds; 8hY)r~!b'
} G
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public String getCountType(){ x]M1UBnMN
return countType; }9dgm[C[b
} gr7_oJ:R
public int getCountId(){ &0TheY;srf
return countId; ;U4X
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} Hs` '](
} Sy55w={
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CountCache.java 7]Yd-vA
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/* R&p5 3n
* CountCache.java t~M_NEPxV
* <k1gc,*
* Created on 2007年1月1日, 下午5:01 %mJ)pMV
* }mK_d9d x
* To change this template, choose Tools | Options and locate the template under 4#uoPkLK
* the Source Creation and Management node. Right-click the template and choose o%iTYR:x
* Open. You can then make changes to the template in the Source Editor. G[ea@u$?
*/ /cn_|DwN5
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package com.tot.count; |@F<ajlV
import java.util.*; Y_B(R
/** j.*}W4`Q_
* [d}1Cq=_
* @author \~>#<@h
*/ #wfR$Cd
public class CountCache { ;'kH<Iq
public static LinkedList list=new LinkedList(); d0d2QRX
/** Creates a new instance of CountCache */ YVi]f2F%
public CountCache() {} AnQRSB (
public static void add(CountBean cb){ #e[5O|V~
if(cb!=null){ P[~a'u
list.add(cb); :n4x}%
} @nK08Kj-
} o^_am>h
} jLg4_N1SD
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CountControl.java g=wnly
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/* t!LvV.g+
* CountThread.java Bdi~B")
* .*{LPfD|
* Created on 2007年1月1日, 下午4:57 YDJc@*D
* !% Md9Mu!o
* To change this template, choose Tools | Options and locate the template under (nm&\b~j
* the Source Creation and Management node. Right-click the template and choose H^~!t{\
* Open. You can then make changes to the template in the Source Editor. ic+iTH
*/ bVym
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package com.tot.count; L`BLkDm
import tot.db.DBUtils; 6IA~bkc}
import java.sql.*; O B:G5B`
/** 0FBifK
* {^F_b% a4z
* @author A'T! og|5
*/ <\u%ZB
public class CountControl{ QQcJUOxT9
private static long lastExecuteTime=0;//上次更新时间 wSGUNP9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Zx6BK=4G
/** Creates a new instance of CountThread */ B(hNBq7
public CountControl() {} .+.Pc_fv
public synchronized void executeUpdate(){ Im2g2]
Connection conn=null; ]4PG[9J@
PreparedStatement ps=null; 0T*jv! q>
try{ /$E1!9J
conn = DBUtils.getConnection(); g"xZ{k_3
conn.setAutoCommit(false); ev`p!p
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Y (Q8P{@(
for(int i=0;i<CountCache.list.size();i++){ d{Z
CountBean cb=(CountBean)CountCache.list.getFirst(); 3JwmLGj}
CountCache.list.removeFirst(); mT;z `*
ps.setInt(1, cb.getCountId()); :gmVX}
ps.executeUpdate();⑴ y9 "!ys
//ps.addBatch();⑵ zPn8>J<.0Q
} zT@vji%Y
//int [] counts = ps.executeBatch();⑶ mYZH]oo
conn.commit(); U<t Qj`
}catch(Exception e){ 0>vm&W<?)
e.printStackTrace(); iVA_a8}
} finally{ k~R_Pq
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try{ CR<*<=rI
if(ps!=null) { 5}f$O
ps.clearParameters(); 1K!7FiqY
ps.close(); .d;/6HD[y
ps=null; %tpjy,
} x9a0J1Nb-h
}catch(SQLException e){} K:y>wyzl
DBUtils.closeConnection(conn); 0 }q/VH57
} Q"KH!Bu%P
} |yS4um(w
public long getLast(){ |m ~|
return lastExecuteTime; ,MdCeA%`
} 9.<$&mVk7`
public void run(){ r*$KF!-dg
long now = System.currentTimeMillis(); %gN8-~$1
if ((now - lastExecuteTime) > executeSep) { mR@iGl\\
//System.out.print("lastExecuteTime:"+lastExecuteTime); rz4S"4
//System.out.print(" now:"+now+"\n"); :E.mU{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
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lastExecuteTime=now; e_Y>[/Om
executeUpdate(); Gz`Zp "i%0
} c#_%|gg
else{ xi ^_C!*J
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]:F]VRPT
} fZgZ
} 8YCtU9D
} 7:]I@Gc'
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 u4%-e)$X
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类写好了,下面是在JSP中如下调用。 UJO+7h'
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<% "w N
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CountBean cb=new CountBean(); !r$/-8b
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); oo`mVRVf
CountCache.add(cb); /@q_`tU
out.print(CountCache.list.size()+"<br>"); $L(,q!DvH
CountControl c=new CountControl(); T. {P}#'|
c.run(); =r`>tWs
out.print(CountCache.list.size()+"<br>"); X)\t=><<
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