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: ;*2Cm'8E
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CountBean.java {R{=+2K!|k
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/* 0jWVp-y
* CountData.java b"
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* %^6F_F_jS
* Created on 2007年1月1日, 下午4:44 =($xG#g`
* Qn2&nD%zi
* To change this template, choose Tools | Options and locate the template under \a3+rNdj
* the Source Creation and Management node. Right-click the template and choose Y8t8!{ytg
* Open. You can then make changes to the template in the Source Editor. ;}p
*/ wVtwx0|1
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package com.tot.count; @IZnFHN
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/** YuwI&)l
* e]$s
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* @author <wHP2|<l*
*/ /G`]=@~
public class CountBean { WTiD[u
private String countType; Rf% a'b
int countId; 0<*<$U
/** Creates a new instance of CountData */ tX~w{|k
public CountBean() {} qmP].sA
public void setCountType(String countTypes){ B`sAk
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this.countType=countTypes; tO&^>&;5
} 86H+h(R/
public void setCountId(int countIds){ ksm~<;td
this.countId=countIds; e+=K d+:k
} iN.n8MN=I
public String getCountType(){ $<OD31T
return countType; y>ktcuML
} eszG0Wu
public int getCountId(){ ~F#j#n(=`q
return countId; ^=*;X;7
} _t ycgq#
} Ew$C
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CountCache.java 5`_SN74o
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/* f?)-}\[IR{
* CountCache.java @E8+C8'
* >.D4co>
* Created on 2007年1月1日, 下午5:01 u]G\H!WkQ
* H%{+QwzZ[j
* To change this template, choose Tools | Options and locate the template under 2>59q$|
* the Source Creation and Management node. Right-click the template and choose JsS-n'gF'
* Open. You can then make changes to the template in the Source Editor. ^kSqsT"
*/ A/?7w
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package com.tot.count; 8l">cVo]T
import java.util.*; TJ*T:?>e
/** oD@7
SF
* /<BI46B\
* @author A_UjC`
*/ 4`=mu}Y2
public class CountCache { {7pli{`
public static LinkedList list=new LinkedList(); ~bpgSP"
/** Creates a new instance of CountCache */ lUMdrt0@z
public CountCache() {} \.}c9*)
public static void add(CountBean cb){ NyuQMU
if(cb!=null){ J?$,c4;W2
list.add(cb); Yz93'HDB
} ijU*|8n{>
} {(?4!rh
} QSf|nNT
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CountControl.java >c}u>]D
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/* 9-m=*|p
* CountThread.java 0C,`h`
* 7 Fsay+a
* Created on 2007年1月1日, 下午4:57 |(^PS8wG
* |
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* To change this template, choose Tools | Options and locate the template under )}O8?d`
* the Source Creation and Management node. Right-click the template and choose IEvdV6{K
* Open. You can then make changes to the template in the Source Editor. `~q <N
*/ UJ6v(:z<
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package com.tot.count; 0+b1vhQ
import tot.db.DBUtils; ,5<Cd,`*
import java.sql.*; C$)onk
/** l%i+cO D
* x'R`.
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* @author \Y}8S/]
*/ mpJ#:}n
public class CountControl{ D^;Uq8NDKq
private static long lastExecuteTime=0;//上次更新时间 @"H>niG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 "" ZQ/t\
/** Creates a new instance of CountThread */ Aq7osU1B
public CountControl() {} @7n"yp*"
public synchronized void executeUpdate(){ 0_t!T'jr7
Connection conn=null; b>JDH1)
PreparedStatement ps=null; qJUK_6|3
try{ y:l\$pGC%
conn = DBUtils.getConnection(); {.mngRQF
conn.setAutoCommit(false); $ L]lHji
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); K@hw.Xq"
for(int i=0;i<CountCache.list.size();i++){ u\JNr}bL
CountBean cb=(CountBean)CountCache.list.getFirst(); Nda *L|
CountCache.list.removeFirst(); UW
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ps.setInt(1, cb.getCountId()); Owk |@6!
ps.executeUpdate();⑴ )53y
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//ps.addBatch();⑵ 65^9
} 5/Uy{Xt
//int [] counts = ps.executeBatch();⑶ 7D5]G-}x.
conn.commit(); lHX72s|V
}catch(Exception e){ b|W=pSTY
e.printStackTrace(); N] sAji*
} finally{ HyWCMK6b
try{ E< fV Z,
if(ps!=null) { !C:$?oU
ps.clearParameters(); =rX>.P%Q 5
ps.close(); }vM("v|M
ps=null; V~5jfcd
} ~/P[J
}catch(SQLException e){} wAW5
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DBUtils.closeConnection(conn); 'b{]:Y
} E^eVvP4uC@
} S^ \Vgi(
public long getLast(){ HC,Se.VYS
return lastExecuteTime; y
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} CizX<Cr}
public void run(){ k\GcHI-
long now = System.currentTimeMillis(); [u*5z.^
if ((now - lastExecuteTime) > executeSep) { ZzT9j~
//System.out.print("lastExecuteTime:"+lastExecuteTime); @J`"[%U
//System.out.print(" now:"+now+"\n"); 9zy!Fq
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); SI-Ops~e
lastExecuteTime=now; OpYY{f
executeUpdate(); :G%61x&=Zc
} }Kbb4]t|"
else{ iAIuxO
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^3L0w}#
} |_@>*Vmg
} Ej8^Zg
} @r/nF5
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 oEZdd#*;
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类写好了,下面是在JSP中如下调用。 }Ud*TOo `
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<% ( 0_2sfS
CountBean cb=new CountBean(); YglmX"fLf
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <B6H. P =
CountCache.add(cb); dVT$ VQg
out.print(CountCache.list.size()+"<br>"); @QP z#-
CountControl c=new CountControl(); M:B=\&.O
c.run(); 338k?nHxv
out.print(CountCache.list.size()+"<br>"); n8ZZ#}Nhg
%>