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: ]bP1gV(b-
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CountBean.java lJ
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/* ~K@p`CRbV
* CountData.java IOddu2.(
* .4J7 ^l
* Created on 2007年1月1日, 下午4:44 FtW=Cc`hC_
* "cwvx8un
* To change this template, choose Tools | Options and locate the template under 8;d./!|'&g
* the Source Creation and Management node. Right-click the template and choose 8b"vXNB.f
* Open. You can then make changes to the template in the Source Editor. )YVs=0j
*/ uquY
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package com.tot.count; Gvl,M\c9-
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/** cwE?+vB
* BsR3$
* @author /%F5u}eW
*/ *7{{z%5Pu
public class CountBean { b63DD(
private String countType; =j%ORD[
int countId;
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/** Creates a new instance of CountData */ T"e"?JSRJ
public CountBean() {} m~tv{#Y
public void setCountType(String countTypes){ G;e)K\[J
this.countType=countTypes; &8dj*!4H
} `j4OKZ
public void setCountId(int countIds){ E~S~Ld%
this.countId=countIds; (g>&ov(d
} nTE\EZ+=2
public String getCountType(){ lQL/I[}
return countType; sWq@E6,I
} b?-KC\}v
public int getCountId(){ |ADg#oX
return countId; xf;Tk
} Hv*+HUc(:
} *iUR1V Y
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CountCache.java fM3ZoH/
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/* i'`>YX
* CountCache.java Dc3bG@K*G
* v807)JwS
* Created on 2007年1月1日, 下午5:01 ^@$T>SB1
* ahR-^^'$
* To change this template, choose Tools | Options and locate the template under ;Ouu+#s
* the Source Creation and Management node. Right-click the template and choose h`D+NZtWm
* Open. You can then make changes to the template in the Source Editor. ?^U1~5ff)
*/ #Wt1Ph_;
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package com.tot.count; v"sN
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import java.util.*; )5x,-m@
/** |iVw7M:
* V7?Pv
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* @author <$8e;:#:
*/ :&m0eZZ%
public class CountCache { qbo
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public static LinkedList list=new LinkedList(); Px`z$~*B:
/** Creates a new instance of CountCache */ 6~Y`<#X5J
public CountCache() {} cKt8e^P
public static void add(CountBean cb){ @|}=W Q
if(cb!=null){ 41o~5:&
list.add(cb); ~GjM:*
} ZRYHsl{F+
} (oB9$Zz!t
} 0{>P^z
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CountControl.java 5dhT?/qvc
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/* CQ#%v%
* CountThread.java tkEup&
* UzUt=s!^H
* Created on 2007年1月1日, 下午4:57 X-5&c$hv
* 6M@m`c
* To change this template, choose Tools | Options and locate the template under WQ1*)h8,9
* the Source Creation and Management node. Right-click the template and choose ^/jALA9!
* Open. You can then make changes to the template in the Source Editor. }"AGX
*/ XLFo"f
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package com.tot.count; H_7X%TvXb
import tot.db.DBUtils; pAdSOR2
import java.sql.*; 3o^oq
/** /-1 F9
* a\v@^4
* @author ]39A1&af}
*/ q}%;O
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public class CountControl{ f"A?\w @
private static long lastExecuteTime=0;//上次更新时间 ,7izrf8
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 lof}isOz
/** Creates a new instance of CountThread */ u9) <i]2
public CountControl() {} <utD&D8w
public synchronized void executeUpdate(){ +X7+:QQ}
Connection conn=null; T\o!^|8
PreparedStatement ps=null; YGr^uTQb
try{ %/=#8v4*
conn = DBUtils.getConnection(); /,2${$c!
conn.setAutoCommit(false); {;ur~KE
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); X&({`Uw<K
for(int i=0;i<CountCache.list.size();i++){ 06vxsT@
CountBean cb=(CountBean)CountCache.list.getFirst(); }5sJd>u5^
CountCache.list.removeFirst(); UP |#WegO
ps.setInt(1, cb.getCountId()); HtGGcO'bqg
ps.executeUpdate();⑴ R(F+Xgje
//ps.addBatch();⑵ @d=4C{g%o
} @@Vf"o+S
//int [] counts = ps.executeBatch();⑶ ~<w9a]
conn.commit(); }u8 D5Q<(
}catch(Exception e){ C6(WnO{6
e.printStackTrace(); (eJYv:
^
} finally{ -4'yC_8t
try{ KRh95B GU
if(ps!=null) { IBr|A
ps.clearParameters(); 4).>b3OhX
ps.close(); ~F9WR5}]
ps=null; ^ql+l~
} IMay`us]:8
}catch(SQLException e){} c`h/x>fa
DBUtils.closeConnection(conn); C/x<_VJzN/
} x?MSHOia`P
} y~pJ|E
public long getLast(){ e6WKZ~
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return lastExecuteTime; zE\@x+k.
} {9C+=v?
public void run(){ MPmsW&
long now = System.currentTimeMillis(); A1(=7ZKz
if ((now - lastExecuteTime) > executeSep) { 2u|}gZts
//System.out.print("lastExecuteTime:"+lastExecuteTime); GwaU7[6
//System.out.print(" now:"+now+"\n"); y!?l;xMS
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); DEkFmmw
lastExecuteTime=now; pn6!QpV5
executeUpdate(); ~wsDg[
} P2;I0 !
else{ 7I_lTu(
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); RxVf:h'l
} csF!*!tta
} `*=Tf
} kM
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//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 -] .Y";
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类写好了,下面是在JSP中如下调用。 Ge]2g0
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<% T7{Z0-
CountBean cb=new CountBean(); =?/RaK/
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); *n=NBkq%/!
CountCache.add(cb); xW;-=Q
out.print(CountCache.list.size()+"<br>"); j7)Xm,wI8
CountControl c=new CountControl(); 2So7fZa^wg
c.run(); U ExK|t
out.print(CountCache.list.size()+"<br>"); yEe4{j$
%>