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: nBk)WX&[K
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CountBean.java n2iJ%_zp
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/* ")d`dj\o
* CountData.java d_IAs
* &mb{.=
* Created on 2007年1月1日, 下午4:44 Y "/]|'p
* ~ 4kc/a
* To change this template, choose Tools | Options and locate the template under #B4%|v;`E?
* the Source Creation and Management node. Right-click the template and choose T}8Y6N<\m
* Open. You can then make changes to the template in the Source Editor. C=eF.FB;'
*/ yu;P +G
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package com.tot.count; \B,(k<
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/** euC&0Ee2
* hEp(A8g)bQ
* @author uD^cxD
*/ yU9DSY\m{
public class CountBean { Z<vKQ4G
private String countType; gHo?[pS%y
int countId; ;qm
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/** Creates a new instance of CountData */ Y'8?.a]'
public CountBean() {} "1%5,
public void setCountType(String countTypes){ EM[WK+9>I{
this.countType=countTypes; DQr Y*nH
} RJd(~1
public void setCountId(int countIds){ Ymg|4%O@
this.countId=countIds; )c)vTZy
} s,]z[qB#$
public String getCountType(){ zx)z/1
return countType; +mn,F};
} Le\?+h42>
public int getCountId(){ PpAu!2lt9
return countId; x^y'P<ypw
} LU={")TdQ
} ]"?)Z
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CountCache.java S[J}UpV
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/* ?vbvBu{a
* CountCache.java Z'.AA OG
* ;IZwTXu !S
* Created on 2007年1月1日, 下午5:01 c}2jmwq
* eQ]~dA8>
* To change this template, choose Tools | Options and locate the template under 0eDHu
* the Source Creation and Management node. Right-click the template and choose m)'=G%y
* Open. You can then make changes to the template in the Source Editor. $w`=z<2yo1
*/ =`H@%
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package com.tot.count; tM'P m
import java.util.*; =Jyu4j *}
/** iMDM1}b
* ~kEI4}O
* @author uFinv2Z'
*/ |R/%D%_g
public class CountCache { A;]}m8(*
public static LinkedList list=new LinkedList(); 1=d6NX)B
/** Creates a new instance of CountCache */ \D*KGd]M0
public CountCache() {} 62ws/8d6f
public static void add(CountBean cb){ Yp^rR }N
if(cb!=null){ +[\FD; >
list.add(cb); a6) BqlJ
} GkQpELO:
} ?iWi
} w=T\3(%j
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CountControl.java `xqr{lhL
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/*
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* CountThread.java rrik,qyv6
* ] Zy5%gI
* Created on 2007年1月1日, 下午4:57 s;01u_
* {#?N
* To change this template, choose Tools | Options and locate the template under Ac2n
* the Source Creation and Management node. Right-click the template and choose {Tq_7,8
* Open. You can then make changes to the template in the Source Editor. V{/?FO?E
*/ a%/9v"}
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package com.tot.count; .$+#1-
import tot.db.DBUtils; 61k"p2?+
import java.sql.*; 0=2@
/** b*c*r dTx
* s %j_H
* @author uxvqMgR
*/ +0nJ
public class CountControl{ Y)* #)f
private static long lastExecuteTime=0;//上次更新时间 EyJJ0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 (X\@t-8
/** Creates a new instance of CountThread */ \fz<.l]
public CountControl() {} A$Hfr8w1u
public synchronized void executeUpdate(){ R{<kW9!
Connection conn=null; jCOIuw
PreparedStatement ps=null; )rn*iJ.e8
try{ #S!)JM|4wk
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); n|9-KTe7|*
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); MyJ%`@+1
for(int i=0;i<CountCache.list.size();i++){ {?}E^5Z*g
CountBean cb=(CountBean)CountCache.list.getFirst(); 0zmE>/O+
CountCache.list.removeFirst(); Z>:NPZODf
ps.setInt(1, cb.getCountId()); `yrB->|vG
ps.executeUpdate();⑴ xr4*{v
//ps.addBatch();⑵ 6t[+pL\b
} s>7}zU]
//int [] counts = ps.executeBatch();⑶ S9]'?|
conn.commit(); m
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}catch(Exception e){ ` Mjj@[
e.printStackTrace(); *\+\5pu0
} finally{ PUp6Q;AdQ
try{ CkOz
if(ps!=null) { c|e~BQdRw
ps.clearParameters(); y" RF;KW>
ps.close(); $p#Bi-&
ps=null; @\0ez<.p}
} A5c%SCq;
}catch(SQLException e){} KX ,S
DBUtils.closeConnection(conn); ;=)k<6
} LDgrR[
} naG=Pq<
public long getLast(){ ?+@n3]`0
return lastExecuteTime; Lb:g4A"
} ]!?;@$wx
public void run(){ e^6)Zz1\
long now = System.currentTimeMillis(); <wN}X#M
if ((now - lastExecuteTime) > executeSep) { Y,<{vLEC
//System.out.print("lastExecuteTime:"+lastExecuteTime); tqE6>"jD
//System.out.print(" now:"+now+"\n"); _{I3i:f9X8
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); DE}K~}sbd
lastExecuteTime=now; 0L2 F[TN
executeUpdate(); DR5\45v
} 36}?dRw#p
else{ ak$f"py
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X`kk]8=
} lA|
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} 'N (:@]4N
} (-UYB9s
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 [+2[`K
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类写好了,下面是在JSP中如下调用。 n4;.W#\
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<% Q 3hKk$Y
CountBean cb=new CountBean(); '}ptj@,
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \=VtHu92=
CountCache.add(cb); ;w{tv($$
out.print(CountCache.list.size()+"<br>"); T"{>t
CountControl c=new CountControl(); '.IW.{;$
c.run(); #++lg{
out.print(CountCache.list.size()+"<br>"); sEp"D+f
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