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: :qt82tbn
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CountBean.java ~`tJvUo0
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/* 9F-ViDI.
* CountData.java Qu,)wfp~
* dw=Xjyk?h
* Created on 2007年1月1日, 下午4:44 ?w c3+?\J
* rPrEEWS0)
* To change this template, choose Tools | Options and locate the template under iT)2 ?I6!
* the Source Creation and Management node. Right-click the template and choose mmh nw(/
* Open. You can then make changes to the template in the Source Editor. Q#d+IIR0gK
*/ ZlwcwoPib
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package com.tot.count; <yX@@8
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/** }0(vR_x
* N6-2*ES
* @author Ae,2Xi
*/ ?];~N5<'
public class CountBean { ORFr7a'K
private String countType; !>"INmz
int countId; f@,hO5h(_|
/** Creates a new instance of CountData */ >TH-Q[
public CountBean() {} c +"O\j'
public void setCountType(String countTypes){ {VrAh*#h
this.countType=countTypes; Vj9`[1}1Z
} #b<lt'gC
public void setCountId(int countIds){ T-<> )N5y
this.countId=countIds; q?gQ
} *NX*/(Q
public String getCountType(){ *$*nY [/5
return countType; ~CjmYP'o
} #lLn='4
public int getCountId(){ 4Tbi%vF{
return countId; q=j/s4~
} SWe!9Y$
} 7,&3=R<
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CountCache.java ocDVCCkxg
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/* PgGrk5;
* CountCache.java e!L sc3@
* )PLc+J.I
* Created on 2007年1月1日, 下午5:01 l[x`*+ON:2
* 1^Y:XJ73
* To change this template, choose Tools | Options and locate the template under ,vHX>)M|
* the Source Creation and Management node. Right-click the template and choose yA`]%U((
* Open. You can then make changes to the template in the Source Editor. [1[[$ Dr
*/ <_FF~lj
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package com.tot.count; f;qKrw
import java.util.*; P(W\aLp
/** BLYk
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* V< 9em7
* @author O!@KM;
*/ ;d'O. i=
public class CountCache { ?!Th-Cc&m
public static LinkedList list=new LinkedList(); B'[3kJ '
/** Creates a new instance of CountCache */ &_Xv:?
public CountCache() {} "KQ\F0/
public static void add(CountBean cb){ o*5e14W(:
if(cb!=null){ R}K5'`[%ZY
list.add(cb); a 7mKshY(
} El8.D3
} P^d.,
} lk *QV
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CountControl.java J{'zkR?Lr
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/* z2EI"'4\9
* CountThread.java c]/O^/
* tMs|UC
* Created on 2007年1月1日, 下午4:57 WZy6K(18"'
* e]L3=R;
* To change this template, choose Tools | Options and locate the template under ]jT[dX|?
* the Source Creation and Management node. Right-click the template and choose L-oPb)
* Open. You can then make changes to the template in the Source Editor. |^&2zyUj/
*/ XP
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package com.tot.count; Fw8X$SE"
import tot.db.DBUtils; tg%WVy2
import java.sql.*; 5eZg+ O
/** +'6ea+$
* Z_ FL=S\
* @author HT;QepY3
*/ U Y?]\4Om
public class CountControl{ D;;o
private static long lastExecuteTime=0;//上次更新时间 j]]ziz,E
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 =;-ju@d
/** Creates a new instance of CountThread */ %RR|QY*
public CountControl() {} oqU#I~ -
public synchronized void executeUpdate(){ -|iA!w#31
Connection conn=null; =S7C(;=4
PreparedStatement ps=null; EKJc)|8
try{ 8~L.6c5U
conn = DBUtils.getConnection(); =dw*B
conn.setAutoCommit(false); ;@;ie8H
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); W0 ,"V'C
for(int i=0;i<CountCache.list.size();i++){ gT\y&
CountBean cb=(CountBean)CountCache.list.getFirst(); {/VL\AW5$
CountCache.list.removeFirst(); jwE(]u
ps.setInt(1, cb.getCountId()); eNk!pI7g
ps.executeUpdate();⑴ `[HoxCV3o
//ps.addBatch();⑵ otnY{r*
} +^3L~?
//int [] counts = ps.executeBatch();⑶ o\V4qekk
conn.commit(); Gpp}Jpj
}catch(Exception e){ 22(]x}`
e.printStackTrace(); ~a0}
} finally{ .$E~.6J %i
try{
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if(ps!=null) { TKs@?Q,J
ps.clearParameters(); rgY?X$1q_
ps.close(); @42lpreT
ps=null; }n&JZ`8<s
} ~}9H<K3V
}catch(SQLException e){} KV&_^xSoh|
DBUtils.closeConnection(conn); v lnUN
} $;j6*,H
} LYo7?rp
public long getLast(){ oDiv9jm
return lastExecuteTime; lNp:2P
} kQiW 5
public void run(){ ^=M(K ''
long now = System.currentTimeMillis(); \(7# N<-
if ((now - lastExecuteTime) > executeSep) { a9q?9X
//System.out.print("lastExecuteTime:"+lastExecuteTime); w+TuS).
//System.out.print(" now:"+now+"\n"); FXwK9
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); yA )+-
lastExecuteTime=now; {*P7)
executeUpdate(); n7YWc5:CaL
} OG$iZiuf
else{ E$zq8-p|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {(:)
} .`8,$"`4)
} ?g1.-'
} DB=cc
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 thboHPml{
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类写好了,下面是在JSP中如下调用。 U=1`. Ove
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<% ,OFr]74\
CountBean cb=new CountBean(); Vy*Z"k
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); `pS)qx.a
CountCache.add(cb); H
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out.print(CountCache.list.size()+"<br>"); ) x O_
CountControl c=new CountControl(); z_0 lMX`
c.run(); 1|$Rzt%ge
out.print(CountCache.list.size()+"<br>"); \$Qm2XKrK
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