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: :dQ B R
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CountBean.java @dPTk"P
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/* )j0TeE1R
* CountData.java /q`xCS
* 9vvx*rD
* Created on 2007年1月1日, 下午4:44 .w8J*JZ
* n' q4
* To change this template, choose Tools | Options and locate the template under VYk!k3qS
* the Source Creation and Management node. Right-click the template and choose Dw<bn<e-
* Open. You can then make changes to the template in the Source Editor. zPjHsulK
*/ }%_ b$
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package com.tot.count; e(GP^oK
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/** Pn>Xbe
* "Pu!dJ5[]
* @author E4~<V=2l
*/ ov_j4j>6P
public class CountBean { &p4&[H?
private String countType; rFj-kojg
int countId; SfaQvstN
/** Creates a new instance of CountData */ n
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public CountBean() {} |m^k_d!d
public void setCountType(String countTypes){ M$>1L
this.countType=countTypes; 6MT1$7|P&x
} rp!oO>F
public void setCountId(int countIds){ -v]Sr33L
this.countId=countIds; n O\"HLM
} z4jR[x,
public String getCountType(){ vnM@QfN
return countType; uP~@U" !
} lE&&_INHQ
public int getCountId(){ 6sx'S?Qa*
return countId; d\R,Q
} { +
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} }}\vV} s
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CountCache.java QSszn`e
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/* /tf5Bv'<
* CountCache.java LHkc7X$
* %'s>QF]'
* Created on 2007年1月1日, 下午5:01 3TY5 ;6
* )GM41t1i
* To change this template, choose Tools | Options and locate the template under &3J_^210
* the Source Creation and Management node. Right-click the template and choose }dWq=)*
* Open. You can then make changes to the template in the Source Editor. SEGri#s
*/ > dI LF
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package com.tot.count; iw8yb;|z;A
import java.util.*; N343qU
/** ;>?rP88t
* kt["m.
* @author =}DR)
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*/ LWz&YF#T-
public class CountCache { ,!Z*5
public static LinkedList list=new LinkedList(); ND>r#(_\
/** Creates a new instance of CountCache */ ifUGY[ L
public CountCache() {} 2[RoxKm
public static void add(CountBean cb){ O4cr*MCb5
if(cb!=null){ Jrti
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list.add(cb); E[@ u
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} |
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} &eCa0s?mI
} z$/_I0[
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CountControl.java p?);eJtV/
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/* .!$*:4ok
* CountThread.java gcPTLh[^Er
* VEqS;~[
* Created on 2007年1月1日, 下午4:57 4E]l{"k<
* =|3ek
* 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 7hlO#PYZ
* Open. You can then make changes to the template in the Source Editor.
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*/ H%UL%l$
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package com.tot.count; wsIW
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import tot.db.DBUtils; aT)BR?OYSJ
import java.sql.*; 4'`{H@]tb
/** E*V`":efS
* {*0<T|<n
* @author `e}bdj
*/ Tx|Ir+f6L
public class CountControl{ E9Np 0M<
private static long lastExecuteTime=0;//上次更新时间 RrX[|GLSJ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 "a
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/** Creates a new instance of CountThread */ [ sN EHf
public CountControl() {} XC0bI,Fu,
public synchronized void executeUpdate(){ -:2$ %
Connection conn=null; :km61
PreparedStatement ps=null; V5sg#|&
try{ i'H/ZwU
conn = DBUtils.getConnection(); wRcAX%n&
conn.setAutoCommit(false); WN?O'E=2
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); [F0s!,P
for(int i=0;i<CountCache.list.size();i++){ b J=Jg~&
CountBean cb=(CountBean)CountCache.list.getFirst(); bJRN;g
CountCache.list.removeFirst(); h{HF8>u[
ps.setInt(1, cb.getCountId()); (l-tvk4Ln
ps.executeUpdate();⑴ NdtB1b
//ps.addBatch();⑵ !sDh4jQ`
} F(k.,0Nc
//int [] counts = ps.executeBatch();⑶ e+$p9k~
conn.commit(); k2c}3 MeP
}catch(Exception e){ v,
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e.printStackTrace(); WG6FQAo^8
} finally{ |Y$uqRdV
try{ 96 q_K84K
if(ps!=null) { {1V($aBl
ps.clearParameters(); QMa;Gy
ps.close(); $@^pAP
ps=null; Hyb3 ;yQ
} k9:{9wW
}catch(SQLException e){} MBt9SXM
DBUtils.closeConnection(conn); OMWbZ>jB
} P3cR l']
} %_+2@\
public long getLast(){ ,uo'c_f(e
return lastExecuteTime; A'q#I>j`
} ]h>_\9qO
public void run(){ T&%ux=Jt
long now = System.currentTimeMillis(); A?CcHw
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if ((now - lastExecuteTime) > executeSep) { Bt>}rYz1
//System.out.print("lastExecuteTime:"+lastExecuteTime); r"``QmM
//System.out.print(" now:"+now+"\n"); ,TXTS*V?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); l>Z5 uSG
lastExecuteTime=now; $FlW1E j
executeUpdate(); E~%jX
}/
} &u /Nf&A
else{ ;A|-n1e>Hc
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 4{hps.$?~
} YVYu:}e3)
} sm0x LZ
} >TOu|r
//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 b7NM#Hb
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类写好了,下面是在JSP中如下调用。 i=i(%yQ%
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<% M)eO6oX|
CountBean cb=new CountBean(); [q/Abz'i
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); qQA}Z*(m
CountCache.add(cb); +?u~APjNN
out.print(CountCache.list.size()+"<br>"); &