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: Yij_'0vZ
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CountBean.java BD2Gv)?g
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/* >)t-Zh:n
* CountData.java "Wg5eML0
* -&h<t/U
* Created on 2007年1月1日, 下午4:44 /lLG|aAe
* &SMM<^P.
* To change this template, choose Tools | Options and locate the template under \2 Yo*jE}
* the Source Creation and Management node. Right-click the template and choose h'B0rVQia>
* Open. You can then make changes to the template in the Source Editor. Pd+Wb3
*/ Ow0( q^H<
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package com.tot.count; KBI36=UV
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/** eIcIl2
* ZdJQ9y
* @author .h-k*F0Ga)
*/ goZw![4l
public class CountBean { >p29|TFbV
private String countType; ]#;u]
int countId; kS62]v]
/** Creates a new instance of CountData */ w""
public CountBean() {} uQl=?085
public void setCountType(String countTypes){ Rhzcm`"
this.countType=countTypes; Og1Hg
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} |@rYh-5
public void setCountId(int countIds){ PmA_cP7~
this.countId=countIds; x75 3o\u!
} ]]hsLOM]
public String getCountType(){ EouI S2e;a
return countType; }F-,PSH
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} V^kl_!@
public int getCountId(){ (m() r0:@
return countId; a?X#G/)
} :0% $u>;O:
} )U+&XjK
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CountCache.java i9^m;Y)^I
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/* F~l:WQAj
* CountCache.java 5XZ\7Z|
* \tfhF#'
* Created on 2007年1月1日, 下午5:01 6C- !^8[f
* T#3`&[
* To change this template, choose Tools | Options and locate the template under /mQ9}E4X
* the Source Creation and Management node. Right-click the template and choose s;,ulME
* Open. You can then make changes to the template in the Source Editor. YH3[Jvzf4
*/ 9u1Fk'cxG,
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package com.tot.count; `aM8L
import java.util.*; #{~3bgY
/** gcF V$
* .~%,eF;l$
* @author Lu[xoQ~I
*/ l j %k/u
public class CountCache { ?m h0^G
public static LinkedList list=new LinkedList(); M5{vYk>,1Q
/** Creates a new instance of CountCache */ SXRND;-W8
public CountCache() {} wV"C ,*V
public static void add(CountBean cb){ 71G00@&w9D
if(cb!=null){ +~?K@n
list.add(cb); -O6\!Wo=-
} GD<pqm`vVY
} *h~(LH"tN
} yHxi^D]
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CountControl.java g?9%_&/})A
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/* ]Czq
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* CountThread.java oI9-jW
* u\@L|rh
* Created on 2007年1月1日, 下午4:57 GI/4<J\
* h<FEe~
* To change this template, choose Tools | Options and locate the template under [zhcb+^5l
* the Source Creation and Management node. Right-click the template and choose E akS(Q?
* Open. You can then make changes to the template in the Source Editor. oT^r
*/ 6gD|QC~;
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package com.tot.count; $F~hL?"?
import tot.db.DBUtils; Ffr6P
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import java.sql.*; n$jf($*
/** V2*m/JyeB
* 5YgUk[J
* @author 0u8(*?
*/ 5U.,iQ(d
public class CountControl{ )q'~<QxI\
private static long lastExecuteTime=0;//上次更新时间 uH8`ipX
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 .iH#8Z
/** Creates a new instance of CountThread */ YbE1yOJ&m
public CountControl() {} ;/ao3Q
public synchronized void executeUpdate(){ 1a;&&!X
Connection conn=null; zNQ|G1o
PreparedStatement ps=null; <P<^,aC/j
try{ E3E$_<^
conn = DBUtils.getConnection(); uT{.\qHo
conn.setAutoCommit(false); -u%'u~s
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); P8;f^3V(+/
for(int i=0;i<CountCache.list.size();i++){ ot.R Gpg%
CountBean cb=(CountBean)CountCache.list.getFirst(); :]-? l4(%
CountCache.list.removeFirst(); AV?<D.<
ps.setInt(1, cb.getCountId()); }S>:!9f
ps.executeUpdate();⑴ z,/y2H2
//ps.addBatch();⑵ qYR+qSAJP
} gb@ |\n
//int [] counts = ps.executeBatch();⑶ My\
conn.commit(); V39)[FH}
}catch(Exception e){ ^1NtvQe@Y\
e.printStackTrace(); |cq%eN
} finally{ 0Z>oiBr4
try{ (r )fx
if(ps!=null) { -~ycr[}x
ps.clearParameters(); g63?(+Fz
ps.close(); N>_d {=P
ps=null; c}g:vh
} X5eTj
}catch(SQLException e){} }lt]]094,
DBUtils.closeConnection(conn); N3g?gb"Ex)
} QTjOLK$e$
} !;YQQ<D
public long getLast(){ ;t}ux
return lastExecuteTime; Y/w) VV
} wq"AW yu
public void run(){ [/I1%6;
long now = System.currentTimeMillis(); vH^^QI:em
if ((now - lastExecuteTime) > executeSep) { `)R@\@jt
//System.out.print("lastExecuteTime:"+lastExecuteTime); nW
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//System.out.print(" now:"+now+"\n"); JTg0T+
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1eDc:!^SD
lastExecuteTime=now; rKys:is
executeUpdate(); 5CuK\<
} uH-*`*
else{ T4{&@b
0*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); CfnRcnms
} 'zhw]L;'g
} 0yxMIX
} id.W"5+
//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 J8yi#A>+
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类写好了,下面是在JSP中如下调用。 DqHVc)9
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<% #/9(^6f:
CountBean cb=new CountBean(); s(I7}oRWsL
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^ok;<fJ
CountCache.add(cb); (N\Zz*PLz
out.print(CountCache.list.size()+"<br>"); `'`T'+0
CountControl c=new CountControl(); WwDxZ>9jw
c.run(); S
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out.print(CountCache.list.size()+"<br>"); \HOOWaapN
%>