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: `G_k~ %
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CountBean.java _j sJS<21
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/* b^^ .$Gu
* CountData.java U-ADdOh"q
*
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* Created on 2007年1月1日, 下午4:44 PC)aVr?@@
* )aAKxC7w
* To change this template, choose Tools | Options and locate the template under Ba#wW
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* the Source Creation and Management node. Right-click the template and choose nvbKW.[<f{
* Open. You can then make changes to the template in the Source Editor. |w+N(wcJ
*/ ; S~
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package com.tot.count; SUN!8
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/** ;hb_jW-0W
* uA;vW\fHr
* @author z)F<{]%
*/ cH48)
public class CountBean { O48*"Z1
private String countType; (~N[j;W,_W
int countId; ><wYk)0E
/** Creates a new instance of CountData */ _?oofE:{
public CountBean() {} @8eQ|.q]Q
public void setCountType(String countTypes){ @(W{_ mw
this.countType=countTypes; >e"vPW*[
} g T{WH67u
public void setCountId(int countIds){ 6-Id{m x
this.countId=countIds; k9m9IE"9=$
} \'CA:9V}
public String getCountType(){ uD4j.%
return countType; n5+Z|<3)
} *W-:]t3CR
public int getCountId(){ brEA-xNWQ
return countId; ]x5+v0
} Xkp?)x3~X
} Sp/<%+2(
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CountCache.java *ry}T=
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/* :r4o:@N'
* CountCache.java -]Y@_T.C
* v2jpao<K
* Created on 2007年1月1日, 下午5:01 2(AuhZ>
* XiO~^=J
* To change this template, choose Tools | Options and locate the template under +SNjU"x
* the Source Creation and Management node. Right-click the template and choose g\]~H%2 ,
* Open. You can then make changes to the template in the Source Editor. {RC&Ub>
*/ :5[1Iepdn
@! {Y9k2
package com.tot.count; v3b+Ddp
import java.util.*; DH Qs_8Df
/** <O0.q.
* I=2b)"t0
* @author $pJw
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*/ #HTq\J!
public class CountCache { YY4q99^K
public static LinkedList list=new LinkedList(); -dS@l'$
/** Creates a new instance of CountCache */ }D[j6+E
public CountCache() {} p(!d,YSE
public static void add(CountBean cb){ s("\]K
if(cb!=null){ ipC
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list.add(cb); vYg>^!Q
} n7/>+V+
} } 89-U
} bm poptfL
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CountControl.java mtmTlGp6Lc
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/* 9Cz|?71
* CountThread.java $.x,[R
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* B[s
* Created on 2007年1月1日, 下午4:57 w:+&i|H >
* 2ElZ&(RZJF
* To change this template, choose Tools | Options and locate the template under 5x"eM=
* the Source Creation and Management node. Right-click the template and choose \}71pzw(
* Open. You can then make changes to the template in the Source Editor. 3X%h?DC
*/ an2Yluc;
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package com.tot.count; 8d7 NESYl
import tot.db.DBUtils; Y_<-.?jf
import java.sql.*; G8&/Ic
/** ^^B~v<uK
* ly#jl5wmT
* @author I-^C6~
*/ a"&cm'\lL
public class CountControl{ +c$:#9$ |
private static long lastExecuteTime=0;//上次更新时间 _FxeZ4\
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @{"?fqo
/** Creates a new instance of CountThread */ MK(~
public CountControl() {} {H*
public synchronized void executeUpdate(){ :$*@S=8 O
Connection conn=null; NfWL3"&X
PreparedStatement ps=null; bTt1y O
try{ F*T$n"^
conn = DBUtils.getConnection(); ]\y]8v5(
conn.setAutoCommit(false); WbwwI)1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); sYbmL`{
for(int i=0;i<CountCache.list.size();i++){ SBI*[
CountBean cb=(CountBean)CountCache.list.getFirst(); !Df>Q5~g
CountCache.list.removeFirst(); .C` YO2,
ps.setInt(1, cb.getCountId()); EbG&[v
ps.executeUpdate();⑴ @H8DGeM
//ps.addBatch();⑵ On|b-
} 5z&>NI
//int [] counts = ps.executeBatch();⑶ {1gT{2/~@
conn.commit(); ^J;rW3#N8
}catch(Exception e){ >Ptu-*
e.printStackTrace(); ]iMqIh"
} finally{ [
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try{ pI_dV44W
if(ps!=null) { adPd}rt;
ps.clearParameters(); L2=:Nac
ps.close(); ( k,?)
ps=null; hr!'
} |nfMoUI
}catch(SQLException e){} KP&xk13)
DBUtils.closeConnection(conn); O7p=N8 V
} q~^!Ck+#*
} [{`2FR:Cd
public long getLast(){ j^%N:BQ&
return lastExecuteTime; \ef:H&r
} b:cy(6G(
public void run(){ v-BQ>-& s
long now = System.currentTimeMillis(); %>$Puy\U
if ((now - lastExecuteTime) > executeSep) { *`8JJs0g
//System.out.print("lastExecuteTime:"+lastExecuteTime); jweX"G54R
//System.out.print(" now:"+now+"\n"); 7]9,J(:Ed
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); c8T| o=`k6
lastExecuteTime=now; Gt+rVJ=v
executeUpdate(); 53 -Owjpx
} )KEW`BC5T
else{ H'JU5nE
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); PW82
Vp.
} Au6Y]
} !6x7^E;c
} CW2)1%1iz
//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 =t`cHs29
}*C*!?pcd
类写好了,下面是在JSP中如下调用。 3I(;c ,S
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<% `2hg?(ul
CountBean cb=new CountBean(); w {"1V7|
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); jwUX?`6jX
CountCache.add(cb); k<5g
out.print(CountCache.list.size()+"<br>"); >ZW|wpO
CountControl c=new CountControl(); Z/dhp0k
c.run(); 4Us_Z{.
out.print(CountCache.list.size()+"<br>"); ]x{.qTtw
%>