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*%o%Lv
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CountBean.java 0gKSjTqo
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/* MG,?,1_ &
* CountData.java t$uj( y>
* OF(tCK
* Created on 2007年1月1日, 下午4:44 KZ/2W9r_,
* M;0\fUh;
* To change this template, choose Tools | Options and locate the template under ':T"nORC
* the Source Creation and Management node. Right-click the template and choose ~</H>Jd
* Open. You can then make changes to the template in the Source Editor. =XUt?5
*/ myZ8LQ&
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package com.tot.count; !wjD6NK
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/** GYri\ <[
* xC$CRzAe5p
* @author HD}3mP
*/ *C^`+*}OE$
public class CountBean { f87lm*wZ
private String countType; s|Zv>Qt
int countId; $Mqw)X&q
/** Creates a new instance of CountData */ ARid
public CountBean() {} @p7*JLO
public void setCountType(String countTypes){ F[oTc^dr
this.countType=countTypes; !*B1Eo--cN
} ]1KF3$n0
public void setCountId(int countIds){ t. kOR<
this.countId=countIds; H|B4.z
} :YN,cI d*
public String getCountType(){ %R*-oQ1T
return countType; yLCJSN$7
} 2-u9%
public int getCountId(){ f(*^zga,
return countId; 'uF"O"*
} E`UEl$($
} nOUF<DNQ
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CountCache.java k*= #XbX
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/* ~YrO>H` B
* CountCache.java 'sTMUPg`
* J]4Uh_>)
* Created on 2007年1月1日, 下午5:01
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* 8|\?imOp\[
* To change this template, choose Tools | Options and locate the template under t9m08K:Y
* the Source Creation and Management node. Right-click the template and choose H5p&dNO
* Open. You can then make changes to the template in the Source Editor. g=n /w
*/ =xsTVT;sj
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package com.tot.count; ]kyGm2Ty9
import java.util.*; Fop'm))C8
/** .
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* wO ?A/s
* @author ,qO2D_
*/ ^
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public class CountCache { r4Jc9Tvd
public static LinkedList list=new LinkedList(); i;}mIsNBY
/** Creates a new instance of CountCache */ +`~6Weay
public CountCache() {} y8=H+Y
public static void add(CountBean cb){ A<s9c=d6
if(cb!=null){ qCgoB 0
list.add(cb); SpX6PwM
} kG$U
} vTUhIFa{
} H~r":A'"*
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CountControl.java $23dcC*hI
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/*
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* CountThread.java xc6A&b>jI
* Q !G^CG
* Created on 2007年1月1日, 下午4:57 6'1m3<G_
* XhG3Of-6
* To change this template, choose Tools | Options and locate the template under O;?Nz:/q
* the Source Creation and Management node. Right-click the template and choose uu+)r
* Open. You can then make changes to the template in the Source Editor. *.F4?i2D
*/ T:(c/>
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package com.tot.count; #Vi:-zyY
import tot.db.DBUtils; `E2HQA@
import java.sql.*; Z`Sbq{Kx
/** L4-v'Z;
* 2io~pk>
* @author MF/@Efjn
]
*/ &i?>mt
public class CountControl{ zsuXN *
private static long lastExecuteTime=0;//上次更新时间 wW+@3bPl
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 $z5
/** Creates a new instance of CountThread */ eJwHeG
public CountControl() {} }:a:E~5y
public synchronized void executeUpdate(){ 8[xl3=
Connection conn=null; 8xN+LL'T{
PreparedStatement ps=null; @Lf-=9
try{ g<$q#l~4xH
conn = DBUtils.getConnection(); TQg~I/
conn.setAutoCommit(false); $c<NEt_\
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); U[t/40W}P
for(int i=0;i<CountCache.list.size();i++){ xb~8uD5
CountBean cb=(CountBean)CountCache.list.getFirst(); @j|=M7B
CountCache.list.removeFirst(); j0+l-]F-
ps.setInt(1, cb.getCountId()); E|v9khN(].
ps.executeUpdate();⑴ XPQY*.l&.
//ps.addBatch();⑵ p?XVO#
} (N
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//int [] counts = ps.executeBatch();⑶ c}r"O8M
conn.commit(); ;o-c.-!F
}catch(Exception e){ o-_H+p6a
e.printStackTrace(); A$ Ok^
} finally{ o{?R z3z
try{ KoKd.%
if(ps!=null) { g,]GzHV1
ps.clearParameters(); Ek%mX"
ps.close(); '$\O*e'
ps=null; Vx*O^cM
} ].r~?9'/
}catch(SQLException e){} {IA3`y~
DBUtils.closeConnection(conn); ::R5F4
}
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} e'0BP,\f_}
public long getLast(){ |Pj]sh[^Y
return lastExecuteTime; "9bd;Tt:
} 4(D/~OG-6
public void run(){ rK} =<R
long now = System.currentTimeMillis(); GLtd6; V
if ((now - lastExecuteTime) > executeSep) { SA[wFc
//System.out.print("lastExecuteTime:"+lastExecuteTime); iw\yVd^]:k
//System.out.print(" now:"+now+"\n"); 'K*. ?M
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); I )wc&>Lc
lastExecuteTime=now; BH\!yxK
executeUpdate(); _-5| "oJ
} <b#1L
else{ @Z2^smf
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); o4F(X0
} ALXie86a8
} &ku.Q3xGs
} +nU=)x?38
//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 ~
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类写好了,下面是在JSP中如下调用。 }NpN<C+
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<% )wyC8` &-
CountBean cb=new CountBean(); -"uOh,G}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); *r(Qy0(
CountCache.add(cb); n5>OZ3 E@
out.print(CountCache.list.size()+"<br>"); HP2J`>oo
CountControl c=new CountControl(); !hWS%m@
c.run(); yB2}[1
out.print(CountCache.list.size()+"<br>"); o'J^kd`
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