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: SOvo%L@
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CountBean.java j8?rMD~
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/* ?YnB:z*eV
* CountData.java Edl .R}&1
* zC!Pb{IaH
* Created on 2007年1月1日, 下午4:44 \C`2z]V%
* t,qz%J&a
* To change this template, choose Tools | Options and locate the template under 4M>E QF&
* the Source Creation and Management node. Right-click the template and choose `YK#m4gc
* Open. You can then make changes to the template in the Source Editor. 0|~3\e/QV
*/ Oy yE0
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package com.tot.count; Kk/cI6`W
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/** fCi1JH;
* `^
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* @author "=*
*/ nPjN\Es6
public class CountBean { <nF1f(ky
private String countType; &=laZxe
int countId; 9TV1[+JWe
/** Creates a new instance of CountData */ uG4Q\,R
public CountBean() {} %~qY\>
public void setCountType(String countTypes){ JPkI+0
this.countType=countTypes; EV N:3
} 5}`e"X
public void setCountId(int countIds){ B k~%
this.countId=countIds; jNP%BNd1f
} 4|KtsAVp{
public String getCountType(){ >('Z9<|r:
return countType; +JY]J89
} xBAASy
public int getCountId(){ t+n+_X
return countId; f_ UwIP
} F vHd`
} H)i%\7F5
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CountCache.java i}Cy q
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/* ]s~%1bd
* CountCache.java 9C\@10 D
* Xldz&&@
* Created on 2007年1月1日, 下午5:01 KgEfhO$W
* 4 UnN~
* To change this template, choose Tools | Options and locate the template under X8(WsN
* the Source Creation and Management node. Right-click the template and choose r r(UE
* Open. You can then make changes to the template in the Source Editor. Z_[jah
*/ n;*W#c
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package com.tot.count; w-?Cg8bq<
import java.util.*; &BQ%df<y\
/** IsP!ZcV;
* ph=U<D4
* @author bd3q207>
*/ z|i2M8
public class CountCache { XB\n4|4
public static LinkedList list=new LinkedList(); .l~g`._
/** Creates a new instance of CountCache */ *]* D^'
public CountCache() {} +AL(K:
public static void add(CountBean cb){ -LEpT$v|
if(cb!=null){ 5gY9D!;:0D
list.add(cb); O@? *5
} - x]gp5
} JbEQ35r
} -gb'DN1BG
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CountControl.java ^ot9Q
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/* KZ/2#`
* CountThread.java 1IV
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* >O}J*4A>+#
* Created on 2007年1月1日, 下午4:57 B;xGTl@8
* XLsOn(U\&
* To change this template, choose Tools | Options and locate the template under doV+u(J~
* the Source Creation and Management node. Right-click the template and choose Z1M{5E
* Open. You can then make changes to the template in the Source Editor. glP
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*/ pt-
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package com.tot.count; o:Q.XWa@MG
import tot.db.DBUtils; ?FwjbG<
import java.sql.*; Af7&;8pM
/** M]M(E) *5
* wT-@v,$
* @author @2)ImgK[
*/ ^Ts8nOGMh
public class CountControl{ J9yB'yE8
private static long lastExecuteTime=0;//上次更新时间 dX5|A_Ex
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Rz!! ;<ye8
/** Creates a new instance of CountThread */ z7um9g
public CountControl() {} !x1ivP
public synchronized void executeUpdate(){ s+XDtO
Connection conn=null; dNgjM
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PreparedStatement ps=null; APT/z0X>
try{ 2x dN0S
conn = DBUtils.getConnection(); f/RDo4
conn.setAutoCommit(false); 'K|tgsvgme
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); iZDZ/hohv
for(int i=0;i<CountCache.list.size();i++){ N3rQ]HZiP
CountBean cb=(CountBean)CountCache.list.getFirst(); 7c.LyvM
CountCache.list.removeFirst(); lM-*{<B
ps.setInt(1, cb.getCountId()); 2@#`x"0
ps.executeUpdate();⑴ _=RK
//ps.addBatch();⑵ 1#
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} c-hhA%@Wq
//int [] counts = ps.executeBatch();⑶ _=;lt O
conn.commit(); Ug,23
}catch(Exception e){ zV"oB9\9O
e.printStackTrace(); ,?zOJ,wl
} finally{ Z@bGLS
try{ O\KSPy7YQ
if(ps!=null) { ~7Jj\@68
ps.clearParameters(); <P4*7:jX
ps.close(); f!aE/e\
ps=null; Qv>rww]
} IYk^eG:;
}catch(SQLException e){} K5SP8<.
DBUtils.closeConnection(conn); ;IX*4E'4s
} Z* L{;
} zaoC
public long getLast(){ Wx-vWWx*Q
return lastExecuteTime; eGh7 ,wngH
} d65t"U
public void run(){ bem-T`>'
long now = System.currentTimeMillis(); "[BDa}Il
if ((now - lastExecuteTime) > executeSep) { Kk_h&by?
//System.out.print("lastExecuteTime:"+lastExecuteTime); }MV=I$S2U
//System.out.print(" now:"+now+"\n"); Ar VNynQ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 8}(ul
lastExecuteTime=now; s/J/kKj*s
executeUpdate(); d T*8I0\+
} rc9Y:(S1l
else{ [Y=X^"PF
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 9 ?~Y
} iu(+
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} #J<IHNRt
} {-?8r>
//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 &\/b(|>
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类写好了,下面是在JSP中如下调用。 {IpIQ-@l
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<% `[zd
CountBean cb=new CountBean(); ]~A<Q{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ZT'Sw%U:
CountCache.add(cb); X0"f>.Lg
out.print(CountCache.list.size()+"<br>"); hpVu
CountControl c=new CountControl(); Qo;#}%}^^
c.run(); )Mj
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out.print(CountCache.list.size()+"<br>"); ';0NWFP
%>