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: P"0S94o:5J
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CountBean.java .lfKS!m2
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/* c[]_gUp8
* CountData.java \P]w^
* ]Q=D'1MM
* Created on 2007年1月1日, 下午4:44 hoI?,[@F
* ;cl\$TDL
* To change this template, choose Tools | Options and locate the template under &P&LjHFK
* the Source Creation and Management node. Right-click the template and choose `_sc_Y|C!
* Open. You can then make changes to the template in the Source Editor. x[7jm"Pz
*/ &~U!X~PpB
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package com.tot.count; h5WS<P
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/** z]ZhvH7-
* Vu '/o[nF>
* @author XnrOC|P$
*/ 1g6AzUXg
public class CountBean { `HvU_ja;
private String countType; ^'i(@{{o\
int countId; tLe!_p)
/** Creates a new instance of CountData */ `O(ec
public CountBean() {} pfgFHNH:
public void setCountType(String countTypes){ T6JN@:8
this.countType=countTypes; a'f"Zdh%w
} ;>_\oZGj_
public void setCountId(int countIds){ 6H67$?jMyJ
this.countId=countIds; S?n k9T+
} q}e"E
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public String getCountType(){ C4],7"Sw
return countType; OiNzN.}d
} 5bM/
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public int getCountId(){ IRNL(9H
return countId; Qk<W(
} \bqIe}3V7
} ~C=I{qzF+
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CountCache.java #pP4\n-~hU
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/*
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* CountCache.java 24PEt%2
* `rsPIOu
* Created on 2007年1月1日, 下午5:01 LnIln[g:
* }r$&"wYM
* To change this template, choose Tools | Options and locate the template under [2#5;')
* the Source Creation and Management node. Right-click the template and choose e*p7(b-
* Open. You can then make changes to the template in the Source Editor. zb.^ _A
*/ HQ~`ha.
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package com.tot.count; `Bk7W]{L
import java.util.*; sS;6QkI"y
/** p3ox%4
* bVmHUcR0
* @author _O)xE9t#ru
*/ Bz<T{f
public class CountCache { nmZz`P9g
public static LinkedList list=new LinkedList(); 0X@!i3eu
/** Creates a new instance of CountCache */ B.CUk.
public CountCache() {} =!T@'P?
public static void add(CountBean cb){ i2KN^"v?N
if(cb!=null){ CsHHJgx
list.add(cb); u~n*P``{
} 's>
}
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} j#QJ5(#
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CountControl.java ST$~l7p
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/* ^Pl(V@
* CountThread.java [ZC]O2'
* D\|$!i}
* Created on 2007年1月1日, 下午4:57 VuA7rIF$66
* NRu_6~^^
* To change this template, choose Tools | Options and locate the template under FJ0Ity4u6
* the Source Creation and Management node. Right-click the template and choose %B?@le+%
* Open. You can then make changes to the template in the Source Editor. {$D[l
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*/ P^V,"B8t
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package com.tot.count; Y~\71QE>
import tot.db.DBUtils; M)S(:Il6Xx
import java.sql.*; 2%|
/** ^mxOQc !
* ?>c*[>LpZ
* @author p3>(ZWPNV
*/ biAI*t
public class CountControl{ (:9yeP1
private static long lastExecuteTime=0;//上次更新时间 Mo?eVtZ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 <xpOi&l
/** Creates a new instance of CountThread */ ql"&E{u?
public CountControl() {} tLCu7%P>
public synchronized void executeUpdate(){ BS3Aczwk
Connection conn=null; %Aaf86pkp
PreparedStatement ps=null; q#LB 2M
try{ sF9{(Us
conn = DBUtils.getConnection(); hojP3 [
conn.setAutoCommit(false); aAM!;3j]B`
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); vJZ0G:1
for(int i=0;i<CountCache.list.size();i++){ 1ocd$)B|}
CountBean cb=(CountBean)CountCache.list.getFirst(); _Z~cJIEU
CountCache.list.removeFirst(); )Z6bMAb0'N
ps.setInt(1, cb.getCountId()); (w4w
ps.executeUpdate();⑴ t^_0w[
//ps.addBatch();⑵ i%BrnjX
} B
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//int [] counts = ps.executeBatch();⑶ 590.mCm
conn.commit(); F`!B!uY
}catch(Exception e){ ;+v5li
e.printStackTrace(); t][U`1>i
} finally{ oCtg{*vp
try{ b-*3]gB
if(ps!=null) { wQ1_Q8 :Z
ps.clearParameters(); Pjz_KO/
ps.close(); Xae0xs
ps=null; wVegr
} JFAmND;+
}catch(SQLException e){} pe^hOzVv
DBUtils.closeConnection(conn); M:t!g%
} DI9hy/T(
} Q`?+w+y7
public long getLast(){ mL5 Nu+#
return lastExecuteTime; :~uvxiF
} :r4]8X-
public void run(){ Q6>7{\8l
long now = System.currentTimeMillis(); s*'L^>iZ
if ((now - lastExecuteTime) > executeSep) { 8aDSRfv*
//System.out.print("lastExecuteTime:"+lastExecuteTime); E`E$ }iLs
//System.out.print(" now:"+now+"\n"); q%H`/~AYM
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Wp2W:JX:
lastExecuteTime=now; mM`zA%=
executeUpdate(); 6d4e~F
} GCrIaZ
else{ u_kcuN\Sq
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^3>Qf
} ,E7+Z' ;
} euxkw]`h6
} [cJQ"G '
//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?AQ&