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: $vdGkz@6
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CountBean.java
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/* @fbB3
* CountData.java H0s,tTK8
* g!O(@Sqp1
* Created on 2007年1月1日, 下午4:44 m4*Rr
* cV5Lp4wY?
* To change this template, choose Tools | Options and locate the template under @qH<4`y.^
* the Source Creation and Management node. Right-click the template and choose c)M_&?J!5
* Open. You can then make changes to the template in the Source Editor. -~
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*/ 2Fce| Tn
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package com.tot.count; Kl$!_ $
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/** Q<r O5 -K
* b#.hw2?a`
* @author vGC^1AM
*/ #uT-_L}sw
public class CountBean { $_l@k=
private String countType; 0bpl3Fh.v
int countId; Db=
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/** Creates a new instance of CountData */ k"V3FXC)
public CountBean() {} 3
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public void setCountType(String countTypes){ >"S'R9t
this.countType=countTypes; `{/z\
} fdN-Zq@'
public void setCountId(int countIds){ N@^?J@#V
this.countId=countIds; Z|
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} Ne.W-,X^cL
public String getCountType(){ A[ ZJS
return countType; _#e='~;
} bI=\n)sEz
public int getCountId(){ z1F[okLA
return countId; S~}?6/G.
} &S<tX]v
} Vr f` :%
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CountCache.java Ni{(=&*=
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/* j+J)S1
* CountCache.java a)[XJLCQ
* NQ{ XIN~
* Created on 2007年1月1日, 下午5:01 `96:Z-!}
* t4UKG&[a
* To change this template, choose Tools | Options and locate the template under iR(A^
* the Source Creation and Management node. Right-click the template and choose '\dFhYs{*
* Open. You can then make changes to the template in the Source Editor. xZL`<3?
*/ 6$b"tdP
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package com.tot.count; ;vF8V`f
import java.util.*; lbgnO s,
/** 2anx]QV4
* V4 Pf?g
* @author xK0VWi
*/ OHqLMBW!!
public class CountCache { FcsEv {#U
public static LinkedList list=new LinkedList(); Ab-S*|B
/** Creates a new instance of CountCache */ * "ER8\
public CountCache() {} ?'$=G4y&?
public static void add(CountBean cb){ P~i^V;g
if(cb!=null){ >RBq&'f
list.add(cb); OcMd'fwO
} +:~&"U^z&
} @iy ^a
} jfS?#;T)
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CountControl.java _ts0@Z_:
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/* HPCgv?E3
* CountThread.java 7J,W#Ql)5
* {{[).o/
* Created on 2007年1月1日, 下午4:57 ^QB/{9 #
* |RwD]2H
* To change this template, choose Tools | Options and locate the template under ,u{d@U^)3@
* the Source Creation and Management node. Right-click the template and choose B8|=P&L7N
* Open. You can then make changes to the template in the Source Editor. o]}b#U8S
*/ pt(GpbtWK
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package com.tot.count; [t<^WmgtxL
import tot.db.DBUtils; #'^p-Jdm
import java.sql.*; IL}pVa00{n
/** /,/T{V[
* @o44b!i
* @author 27E6S)zv
*/ p2!x8`IB*
public class CountControl{ -deY,%
private static long lastExecuteTime=0;//上次更新时间 -d%bc?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 TpZ) wC
/** Creates a new instance of CountThread */ 8:L%-
public CountControl() {} NV*aHci
public synchronized void executeUpdate(){ @*q\$Eg}2
Connection conn=null; ?Hf^&yo
PreparedStatement ps=null; Gc4N)oq)}b
try{ =@binTC4
conn = DBUtils.getConnection(); cIja^xD
conn.setAutoCommit(false); %6L!JN
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?");
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for(int i=0;i<CountCache.list.size();i++){ gJ c5Y
CountBean cb=(CountBean)CountCache.list.getFirst(); mv SNKS
CountCache.list.removeFirst(); KHcfP7
ps.setInt(1, cb.getCountId()); ^P:9iu)+]~
ps.executeUpdate();⑴ |vTirZP
//ps.addBatch();⑵ .-`7Av+7
} Rr4r[g#
//int [] counts = ps.executeBatch();⑶ vV#Jl)
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conn.commit(); +tdt>)a
}catch(Exception e){ w^p
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e.printStackTrace(); 0d`s(b54;O
} finally{ REoFP;H~
try{ %9-).k
if(ps!=null) { =NF},j"
ps.clearParameters(); 05DK-Wh?
ps.close(); >Bskw2
ps=null; -YA1Uk
} \0(QO8.
}catch(SQLException e){} mV`Z]-$$i
DBUtils.closeConnection(conn); # u^F B
} *ta|,
} sTeL4g|%{
public long getLast(){ %nF6n:| :
return lastExecuteTime; \[]36|$LS
} :8E(pq|1PB
public void run(){ 5U3="L
long now = System.currentTimeMillis(); k2<VUeW5
if ((now - lastExecuteTime) > executeSep) { \ zhT1#O
//System.out.print("lastExecuteTime:"+lastExecuteTime); H]UM2.
//System.out.print(" now:"+now+"\n"); iIcO_ZyA
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "]kaaF$U%
lastExecuteTime=now; V`S6cmwdc\
executeUpdate(); uzho>p[ae
} BA A)IQF
else{ }n:'@}
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); F{]dq/{
} 1reJ7b0
} G:c)e,pD
} *@cXBav/<
//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 b&HA_G4
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类写好了,下面是在JSP中如下调用。 ;|soc:aH
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<% :~zK0v"
CountBean cb=new CountBean(); 9i yNR!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); d@7
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CountCache.add(cb); WkXa%OZ
out.print(CountCache.list.size()+"<br>"); 2P!Pbl<
CountControl c=new CountControl(); i)+@'!6
c.run(); NLoJmOi;L7
out.print(CountCache.list.size()+"<br>"); Eae]s8ek9
%>