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: 6*r#m%|
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CountBean.java t;/s^-}
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/* mnm7{?#[
* CountData.java IDn$w^"
* +JlPQ~5
* Created on 2007年1月1日, 下午4:44 SDHJX8Hq
* u?%FD~l:uU
* To change this template, choose Tools | Options and locate the template under /+JHnedK
* the Source Creation and Management node. Right-click the template and choose W:S?_JM
* Open. You can then make changes to the template in the Source Editor. zkb[u"
*/ mO8E-D*3
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package com.tot.count; sp8P[W1a
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/** S!6 ? b5
* 9?38/2kX4
* @author ^+k~{F,)
*/ e754g(|>b
public class CountBean { O]VHX![Y$
private String countType; pz0Q@ n/X
int countId; UB2Ft=
/** Creates a new instance of CountData */ a%XF"*^v
public CountBean() {} 6z2W N|78
public void setCountType(String countTypes){ /L^pU-}Z0
this.countType=countTypes; L&LAh&%{2
} dBb
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public void setCountId(int countIds){ F9Co m}
this.countId=countIds; r$WBEt,B
} cP2n,>:
public String getCountType(){ Cc}3@Nf{/
return countType; #w1E3ahaX
} 6.6;oa4j
public int getCountId(){ E
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return countId; vp&N)t_
} mbZn[D_zi
} 6^NL>|?
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CountCache.java FT[of(g^
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/* kps}i~Jb
* CountCache.java |YcYWok
* ?X^.2+]*&
* Created on 2007年1月1日, 下午5:01 }P\ J?8
* BG^)?_69
* To change this template, choose Tools | Options and locate the template under Dj9ecV`
* the Source Creation and Management node. Right-click the template and choose EV[ BB;eb
* Open. You can then make changes to the template in the Source Editor. %v)+]Ds{
*/ {&uN q^Ch
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package com.tot.count; F#KUu3;B
import java.util.*; WGA"e
/** p>h}k_s
* #&,~5
* @author I''X\/|
*/ V i<6i0
public class CountCache { ,u S)N6'b6
public static LinkedList list=new LinkedList(); THy{r_dx
/** Creates a new instance of CountCache */ AYsiaSTRqW
public CountCache() {} ,Q,3^v-
public static void add(CountBean cb){ e !N%
if(cb!=null){ Y,M2D
list.add(cb); UFGUP]J>
} _jM+;=f
} BT|n+Y[
} OMm'm\+/
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CountControl.java :V~
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/* nj=nSD
* CountThread.java v9MliD'
* D:0?u_[W
* Created on 2007年1月1日, 下午4:57 +ux170Cd3
* gQ$0 |0O
* To change this template, choose Tools | Options and locate the template under %@^9(xTE
* the Source Creation and Management node. Right-click the template and choose Pf#DBW*
* Open. You can then make changes to the template in the Source Editor. q'KXn0IY#
*/ ,% *Jm
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package com.tot.count; F0KNkL>&g
import tot.db.DBUtils;
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import java.sql.*; @r]1;KG
/** 1xj w=
* 48LzI@H&
* @author u85?f
*/ 9t+:L(*pK
public class CountControl{ 6yK"g7
private static long lastExecuteTime=0;//上次更新时间 ~F13}is
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 jygKw+C
/** Creates a new instance of CountThread */ !~`aEF3
public CountControl() {} paZcTC
public synchronized void executeUpdate(){ .6A{
Connection conn=null; suE#'0K
PreparedStatement ps=null; n0b{Jg *
try{ M9Qx F
conn = DBUtils.getConnection(); j"9Zaq_
conn.setAutoCommit(false); 1O+$"5H
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); l
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for(int i=0;i<CountCache.list.size();i++){ :Fdk`aC
CountBean cb=(CountBean)CountCache.list.getFirst(); GB{Q)L
CountCache.list.removeFirst(); ,
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ps.setInt(1, cb.getCountId()); )F m'i&F_
ps.executeUpdate();⑴ xM13OoU
//ps.addBatch();⑵ sfR0wEqI
} Fiaeo0
//int [] counts = ps.executeBatch();⑶ rq|>z .
conn.commit(); 9
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}catch(Exception e){ 9d8U@=
e.printStackTrace();
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} finally{ K}8wCS F
try{ J<-2dvq
if(ps!=null) { T1M>N
ps.clearParameters(); -)[~%n#X+t
ps.close(); G\#dMCk?
ps=null; K-n]m#U4o
}
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}catch(SQLException e){} X!K:V~WG
DBUtils.closeConnection(conn); #Ti5G"C
} !Q{~f;L
} Nrzg>WQa
public long getLast(){ e!P]$em|1E
return lastExecuteTime; Q+Ya\1$6A
} /JmWiBQIn
public void run(){ 0RP{_1k
long now = System.currentTimeMillis(); # N'_~:H
if ((now - lastExecuteTime) > executeSep) { vjd;*ORB
//System.out.print("lastExecuteTime:"+lastExecuteTime); [t"#4[
//System.out.print(" now:"+now+"\n"); )w0K2&)A
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); r-ljT<f%J[
lastExecuteTime=now; VE*&t>I
executeUpdate(); ^K[[:7Aem
} 4_w{~
else{ '
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Vm%0436wOY
} /,3:<I
} >:P-3#e*
} j,v2(e5:
//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 `.YMbj#T
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类写好了,下面是在JSP中如下调用。 iQz
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<% /igbn
CountBean cb=new CountBean(); A#CG D0T
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); gF&HJF 0x
CountCache.add(cb); ju(QSZ|;
out.print(CountCache.list.size()+"<br>"); `:5W1D(
CountControl c=new CountControl(); y])z,#%ED
c.run(); U_AmRiy
out.print(CountCache.list.size()+"<br>"); :{x
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