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: hjgB[
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CountBean.java {6tj$&\)
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/* jAcrXB*
* CountData.java j2RdBoCt
* jf^BEz5
* Created on 2007年1月1日, 下午4:44 FPE%h=sw
* FTQNS8
* To change this template, choose Tools | Options and locate the template under ,x=S)t
* the Source Creation and Management node. Right-click the template and choose _M)
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* Open. You can then make changes to the template in the Source Editor. `oU|U!|
*/ |Zk2]eUO+
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package com.tot.count; o* ~aB_
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/** g.*DlD%%
* dSI<s^n
* @author n'@*RvI:
*/ .Im=-#EN
public class CountBean { ;Rljx3!N
private String countType; :2.<JUDM
int countId; mKBO<l{S
/** Creates a new instance of CountData */ Am!OLGG4
public CountBean() {} IG Ax+3V
public void setCountType(String countTypes){ hS1I ;*t
this.countType=countTypes; b]gVZ-
} a*&(cn
public void setCountId(int countIds){ KL yI*`
this.countId=countIds; neQ~h4U"
} bXi!_'z$
public String getCountType(){ 7^7Jh&b)/
return countType; ,M9e *
} +BVY9U?\"
public int getCountId(){ tZG l^mA"g
return countId; #g/m^8n?s
} !nsx!M
} j5[Y0)pV\
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CountCache.java %Gl1Qi+Po_
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/* zI0d
* CountCache.java +e,c'.
* ,{; *b
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* Created on 2007年1月1日, 下午5:01 JOz4O
* 2EOx],(|
* To change this template, choose Tools | Options and locate the template under f92z/5%V
* the Source Creation and Management node. Right-click the template and choose @QMy!y_K~m
* Open. You can then make changes to the template in the Source Editor. UwxszEHC
*/ @qpj0i+>*
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package com.tot.count; tpblm|sW
import java.util.*; Gr 4v&Mz:
/** fwvwmZW
* HB{'MBs
* @author SK#&%Yk
*/ 4l7
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public class CountCache { P2@Z7DhQ
public static LinkedList list=new LinkedList(); e=nvm'[h
/** Creates a new instance of CountCache */ BA2J dU
public CountCache() {} Ta[\BWR2
public static void add(CountBean cb){ 1Au+X3
if(cb!=null){ `yP`5a/
list.add(cb); /z_]7]
} aL_/2/@X8
} sQJGwZ7
} "%)g^Atp>
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CountControl.java t>AOF\
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/* 5|=J\Lp2I
* CountThread.java :EAh%q
* 0QT:@v2R
* Created on 2007年1月1日, 下午4:57 } lDX3h
* y|)VNnWM
* To change this template, choose Tools | Options and locate the template under P6O\\,B1A
* the Source Creation and Management node. Right-click the template and choose 33EF/k3vW
* Open. You can then make changes to the template in the Source Editor. YrJUs]A
*/ eZ+6U`^t
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package com.tot.count; |1"&[ .
import tot.db.DBUtils; 9=~ZA{0J
import java.sql.*; 9(J,&)J
/** p<{P#?4 g
* v2 E <~/|
* @author +C8O"
*/ \yu7,v
public class CountControl{ Q"ZpT
private static long lastExecuteTime=0;//上次更新时间 0F@ ~[W|2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 [#C6K '
/** Creates a new instance of CountThread */ Hf@4p'
public CountControl() {} ~1%*w*
public synchronized void executeUpdate(){ ;aV3j/
Connection conn=null; =aZ d>{Y
PreparedStatement ps=null; y $\tqQ
try{ ^hiY6N &
conn = DBUtils.getConnection(); 0\{dt4nW&O
conn.setAutoCommit(false); 4hy-M>!D|
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); h@Ea5x
for(int i=0;i<CountCache.list.size();i++){ L?j0t*do
CountBean cb=(CountBean)CountCache.list.getFirst(); \1jThJn
CountCache.list.removeFirst(); W06#|8,{v
ps.setInt(1, cb.getCountId()); ?UAuUFueA
ps.executeUpdate();⑴ XQ]vJQYIR
//ps.addBatch();⑵ \^*:1=|7u]
} XZb=;tYo
//int [] counts = ps.executeBatch();⑶ )b #5rQ
conn.commit(); y\Aa;pL)RQ
}catch(Exception e){ 3"7Q[9Oj
e.printStackTrace(); Ik$$Tn&;
} finally{ D[/fs`XES
try{ ANFes*8j
if(ps!=null) { ZK8)FmT_<O
ps.clearParameters(); B{`adq?pW
ps.close(); J)>DsQ+Cj
ps=null; |@iM(MM[?
} 1H-Y3G>jN
}catch(SQLException e){} FC] *^B
DBUtils.closeConnection(conn); UeO/<ml3>J
} Y2x|6{ #
} UHZ&7jfl
public long getLast(){ ZPmqoR[
return lastExecuteTime; x 4+WZYv3
} 94+^K=lAX
public void run(){ o>r
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long now = System.currentTimeMillis(); zsXgpnlHT
if ((now - lastExecuteTime) > executeSep) { E+lR&~mK=
//System.out.print("lastExecuteTime:"+lastExecuteTime); T;92M}\
//System.out.print(" now:"+now+"\n"); no3yzF3Hi
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); k~8-Eu1
lastExecuteTime=now; 1 %P-X!
executeUpdate(); t2o{=!$WH
} o'#& =h$_
else{ $Y|OGZH8E
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); jg710.v:
} ;#85 _/
} ,%TBW,>
} >J7slDRo
//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 <-v
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类写好了,下面是在JSP中如下调用。 +>#SNZ[
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<% !i;6!w
CountBean cb=new CountBean(); r'OqG^6JFN
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =y][j+WH
CountCache.add(cb); r@4A%ql<
out.print(CountCache.list.size()+"<br>"); ]%Eh"
CountControl c=new CountControl(); [<#jK}g
c.run(); -Q n-w3~&
out.print(CountCache.list.size()+"<br>"); !q2zuxq!R
%>