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: DZJeup?Z
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CountBean.java 7.%f01/i
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/* )j\r,9<K+5
* CountData.java 9#u }^t
* {U(Bfe^a,
* Created on 2007年1月1日, 下午4:44 BApa^j\?
* ]X*YAPv
* To change this template, choose Tools | Options and locate the template under 9^oo-,Su_
* the Source Creation and Management node. Right-click the template and choose GL/ KB
* Open. You can then make changes to the template in the Source Editor. /a%*u6z@
*/ 9QX4R<"wUg
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package com.tot.count; DK)u)?!
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/** O8gfiQqF&
* ?3[tJreVj
* @author pXssh
*/ Dft4isyt^
public class CountBean { 9 >%+bA(
private String countType; \ZqK\=
int countId; w.tW=z5
/** Creates a new instance of CountData */ >
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public CountBean() {} BjYOfu'~z
public void setCountType(String countTypes){ H;qJH1EdD
this.countType=countTypes; +hpSxdAz4
} 0"TgLd
public void setCountId(int countIds){ fc3 Fi'^
this.countId=countIds; NP "ylMr7P
} 6?O}Q7G
public String getCountType(){ U>oW~Z
return countType; 0k%hY{
} `\wUkmH
public int getCountId(){ Bn{)|&;
return countId; 1XCmMZ
} L+73aN
} HQl~Dh0DJ
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CountCache.java WI6(#8^p
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/* !Pw$48cg
* CountCache.java XYts8}y5
* "i&fp:E0
* Created on 2007年1月1日, 下午5:01 {f-XyF1`
* )PwQ^||{
* To change this template, choose Tools | Options and locate the template under +uELTHH=
* the Source Creation and Management node. Right-click the template and choose w3d34*0$
* Open. You can then make changes to the template in the Source Editor. ^eobp.U
*/ YN/u9[=`
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package com.tot.count; `T=1<Tw c
import java.util.*; GJvp{U}y9I
/** n_J5zQJ
* ?;_H{/)m
* @author E.9^&E}PG
*/ cg{Gc]'1#
public class CountCache { g*F~8+]Y
public static LinkedList list=new LinkedList(); Y!M~#oqio
/** Creates a new instance of CountCache */ Mo_$b8i
public CountCache() {} bTiBmS
public static void add(CountBean cb){ W=3? x
if(cb!=null){ V;k#})_-
list.add(cb); o ~;M"
} @*SA$9/l
} w
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} 1#]B^D
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CountControl.java ~?CS_B *
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/* %{U"EZ]D!
* CountThread.java 5*Btb#:
* `4skwvS=
* Created on 2007年1月1日, 下午4:57 p=vV4 C:
* aV#h5s
* To change this template, choose Tools | Options and locate the template under _\UIc;3Gl
* the Source Creation and Management node. Right-click the template and choose l77'Lne
* Open. You can then make changes to the template in the Source Editor. @C=m?7O98
*/ L$kgK# T
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package com.tot.count; ]hL:33
import tot.db.DBUtils; u3ST;
import java.sql.*; L@?e:*h
/** a5)JkC
* 1U'ZVJ5bpK
* @author #hy+ L
*/ AC'lS
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public class CountControl{ >P<'L4;
private static long lastExecuteTime=0;//上次更新时间 <n\i>A3`,S
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 qEZ!2R^`G
/** Creates a new instance of CountThread */ 1LX)4TCC
public CountControl() {}
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public synchronized void executeUpdate(){ JL``iA
Connection conn=null; c@9##DPn
PreparedStatement ps=null; &y\igX1
try{ (Igu:=
conn = DBUtils.getConnection(); L0xsazX:x
conn.setAutoCommit(false); 9OfU7_m
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); K'V 2FTJI
for(int i=0;i<CountCache.list.size();i++){ cl_TF[n?
CountBean cb=(CountBean)CountCache.list.getFirst(); 7VY8CcL
CountCache.list.removeFirst(); x%pRDytA
ps.setInt(1, cb.getCountId()); onib x^Fcd
ps.executeUpdate();⑴ NN mM#eB:4
//ps.addBatch();⑵ S}b~_}
} F)7j@h^
//int [] counts = ps.executeBatch();⑶ Cx,-_
conn.commit(); <S&]$?`{Wi
}catch(Exception e){ 5e8xKL
e.printStackTrace(); ki#bPgT
} finally{ )'t&q/Wn
try{ J)KnE2dw5
if(ps!=null) { ;Gh>44UM[
ps.clearParameters(); /=@e &e
ps.close(); =W<[Fe3
ps=null; tH,sql)
} B$j' /e-Zk
}catch(SQLException e){} h;nQxmJ9
DBUtils.closeConnection(conn);
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} ,Y-S(
} 2LC
w*eT{)
public long getLast(){ #QS?s8IrW
return lastExecuteTime; TaWaHf
} -x5F;d}
public void run(){
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long now = System.currentTimeMillis(); FB_NkXR
if ((now - lastExecuteTime) > executeSep) { dXK-&Po'
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^7^2D2[
//System.out.print(" now:"+now+"\n"); b` zET^F
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); fM2^MUp[=1
lastExecuteTime=now; %/!+(7
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executeUpdate(); <]'|$8&jY
} WL:0R>0
else{ c 6q/X*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); "koo` J
} *6P'q4)
} e=L*&X
} \%4|t,en
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 h$/JGm5uDb
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类写好了,下面是在JSP中如下调用。 "k, K ~@}
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<% I)lC{v
CountBean cb=new CountBean(); NNp}|a9
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _#vGs:-x&
CountCache.add(cb); wASX\D }
out.print(CountCache.list.size()+"<br>"); GFt1
CountControl c=new CountControl(); yquAr$L!
c.run(); ]x_F{&6U8
out.print(CountCache.list.size()+"<br>"); shzG
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