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!;PV^6x
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CountBean.java rQyjNh
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/* +{RTz)e?*
* CountData.java \~"Ub"~I
* 6(rN(C
* Created on 2007年1月1日, 下午4:44 N+@ Ff3M
* rM"27ud[`_
* To change this template, choose Tools | Options and locate the template under .
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* the Source Creation and Management node. Right-click the template and choose oJ\g0|\qwe
* Open. You can then make changes to the template in the Source Editor. k$JOHru
*/ *LU/3H|}
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package com.tot.count; 6Eu(C]nC(
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/** )38%E;T{X
* ; Byt'S
* @author FV/t
*/ c|;n)as9(%
public class CountBean { .8u@/f%pV
private String countType; #Uu,yHMv:;
int countId; 2Y23!hw
/** Creates a new instance of CountData */ |w}j!}u
public CountBean() {} dN)8r
public void setCountType(String countTypes){ J\Pb/9M/
this.countType=countTypes; oDMPYkpTu
} w9G|)UDib
public void setCountId(int countIds){ h_[{-WC
this.countId=countIds; gS5MoW1
} Y=O+d\_W
public String getCountType(){ Syy{ ^Ae}
return countType; rZJJ\ , |
} wW1VOj=6V"
public int getCountId(){ {zvaZY|K"
return countId; m^}|LB:5
} Cl<!S`
} CTRUr"
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CountCache.java -smN}*3[
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/* uBx\xeI
* CountCache.java w;`Jj-
* $|- Lw!)D
* Created on 2007年1月1日, 下午5:01 m0TV i] v
* 2c 0;P
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* To change this template, choose Tools | Options and locate the template under 1vj@qw3
* the Source Creation and Management node. Right-click the template and choose MmN{f~Kq9
* Open. You can then make changes to the template in the Source Editor. b;UBvwY_
*/ qqf`z,u
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package com.tot.count; BZ?3=S1*
import java.util.*; pqb'L]
/** $qQYxx@
* kg]6q T;Y
* @author E(4c&
*/ |6JKB'
public class CountCache { 6+IhI?lI=
public static LinkedList list=new LinkedList(); _w4G|j$C
/** Creates a new instance of CountCache */ P);s0Y|@H
public CountCache() {} DJ, LQj
public static void add(CountBean cb){ i *.Y
if(cb!=null){ z_$c_J
list.add(cb); YQG<Q
} i"0Bc{cQ
} _M%S
} ~4{q
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CountControl.java )OV0YfO
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/* iH }-
* CountThread.java q5SPyfE[
* P[
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* Created on 2007年1月1日, 下午4:57 g8##Be
* c a_mift
* To change this template, choose Tools | Options and locate the template under "CJ~BJI%
* the Source Creation and Management node. Right-click the template and choose gM3:J:N
* Open. You can then make changes to the template in the Source Editor. e.n(NW
*/ "=Br&FN{|
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package com.tot.count; 4|`>}Nu
import tot.db.DBUtils; CLrX!JV>
import java.sql.*; \9VF)Y.ke
/** Q6qW?*Y
* p@^G)x
* @author 'ztOl`I5V
*/ 90<g=B
public class CountControl{ *H
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private static long lastExecuteTime=0;//上次更新时间 gm-[x5O"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 .xsfq*3e5
/** Creates a new instance of CountThread */ ^HC6v;K
public CountControl() {} <=*f
public synchronized void executeUpdate(){ bqcCA91
Connection conn=null; N y'\Q"Y]
PreparedStatement ps=null; ,2S!$M
try{ @L3XBV2
conn = DBUtils.getConnection(); 2FIL@f|\7z
conn.setAutoCommit(false); y/Xs+ {x
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 'k,2*.A
for(int i=0;i<CountCache.list.size();i++){ p'K`K\X
CountBean cb=(CountBean)CountCache.list.getFirst(); jzbq{#
CountCache.list.removeFirst(); U
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ps.setInt(1, cb.getCountId()); :-1|dE)U
ps.executeUpdate();⑴ R/hIXO
//ps.addBatch();⑵ h !^=
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} qiNVaV\wr|
//int [] counts = ps.executeBatch();⑶ g_Z
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conn.commit(); @sXv5kZ:
}catch(Exception e){ ,|]JaZq
e.printStackTrace(); ~#pATPW@(
} finally{ p~$cwbQ!
try{ u.GnXuax
if(ps!=null) { gg/`{
ps.clearParameters(); ?_NKyiu95
ps.close(); h[mT4e3c
ps=null; ;77K1
} |\,OlX,
}catch(SQLException e){} &xnQLz:#
DBUtils.closeConnection(conn); vF27+/2+R
} S+T/(-W
} h aAY =:
public long getLast(){ "?8)}"/f
return lastExecuteTime; |?!i},Ki;
} &W2*'$j"_
public void run(){ N6Mr#A-{
long now = System.currentTimeMillis(); IO\4dU)
if ((now - lastExecuteTime) > executeSep) { o:Fq|?/e
//System.out.print("lastExecuteTime:"+lastExecuteTime); FnO@\{M"A
//System.out.print(" now:"+now+"\n"); }s~c(sL?;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); /{^k8
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lastExecuteTime=now; Pxlc RF
executeUpdate(); r]3-}:vU
} j6m;03<|
else{ WMB%?30
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -> cL)
} 5;a*Xf%V
} :"%/u9<A
} p`"k=tZ{
//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 @5>#<LV=E#
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类写好了,下面是在JSP中如下调用。 :viW
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<% }%|ewy9|CW
CountBean cb=new CountBean(); J&xZN8jW
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); M8/a laoT
CountCache.add(cb); 7r:h_r-
out.print(CountCache.list.size()+"<br>"); 02-ql
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CountControl c=new CountControl(); ![_x/F9
c.run(); XNz+a|cF
out.print(CountCache.list.size()+"<br>"); [YDSS/
%>