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: tkWWR%c"
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CountBean.java 8|7fd|6~
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/* SDV} bN
* CountData.java "P< drz<
* _y`'T;~OY
* Created on 2007年1月1日, 下午4:44 a2iaP
* ?S!lX[#v
* To change this template, choose Tools | Options and locate the template under v}-'L#6
* the Source Creation and Management node. Right-click the template and choose 4 !~JNO
* Open. You can then make changes to the template in the Source Editor. d OqwF
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*/ SR~~rD|V
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package com.tot.count; l4u`R(!n5
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/** QsI>_<r
* 2NsI3M4$8
* @author 05nG|
*/ [ OMcSd|nf
public class CountBean { ;wDcYs
private String countType; I2|iqbX40Q
int countId; s<z{ (a
/** Creates a new instance of CountData */ sKjg)3Sl
public CountBean() {} S! ,.#e (Y
public void setCountType(String countTypes){ L ! yl^c
this.countType=countTypes; ^b;.zhp8;N
} v"_hWJ)
public void setCountId(int countIds){ ]Rnr>_>x;
this.countId=countIds; 6P?
} lGjmw"/C
public String getCountType(){ 1>57rx"l
return countType; 2}I1z_dq~
} v8
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public int getCountId(){ GRO[&;d`
return countId; A#2Fd7&
} -UPdgZ_Vxz
} 8K6yqc H
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CountCache.java 7qgHH p
#\@*C=
/* e}kEh+4
* CountCache.java ph%/;?wY
* ?$pp%
* Created on 2007年1月1日, 下午5:01 U`IDZ{g
* hM/|k0YV
* To change this template, choose Tools | Options and locate the template under @\z2FJ79w
* the Source Creation and Management node. Right-click the template and choose 5sFp+_``
* Open. You can then make changes to the template in the Source Editor. /V2^/`&;a
*/ /u*((AJ?Qv
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package com.tot.count; 2^Q)~sSf9
import java.util.*; e6QUe.S
/** : )cPc7$8
* F^3Q0KsT
* @author DE^{8YX,
*/ u
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public class CountCache { +P6q
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public static LinkedList list=new LinkedList(); /b@8#px
/** Creates a new instance of CountCache */ yFH)PQ_
public CountCache() {} |.)oV;9
public static void add(CountBean cb){ }O<=!^Y;A
if(cb!=null){ j0Kj>
list.add(cb); AWi~qzTZ
} \=XAl >}\
} r|{h7'
} xCEEv5(5
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CountControl.java !WR(H&uBr\
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/* co|jUDu>W
* CountThread.java F(Pe@ #)A
* S}cpYjnH8
* Created on 2007年1月1日, 下午4:57 m5v9:5{
* V&eti2&zO
* To change this template, choose Tools | Options and locate the template under }'b3'/MJ
* the Source Creation and Management node. Right-click the template and choose %kxq" =3
* Open. You can then make changes to the template in the Source Editor. 8&IsZPq%l
*/ z+@aQ@75
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package com.tot.count; m$NBG w
import tot.db.DBUtils; P|!GXkS
import java.sql.*; `kpX}cKK}
/** X2}\i5{
* hJ (Q^Z
* @author 5IOOV Yl
*/ `{gkL-
public class CountControl{ [V|,O'X ~
private static long lastExecuteTime=0;//上次更新时间 rh5R kiF~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 lF2im5nZ?
/** Creates a new instance of CountThread */ >8"oO[U5>
public CountControl() {} r1\c{5Wt
public synchronized void executeUpdate(){ 'nz;|6uC
Connection conn=null; j\B]>PP5
PreparedStatement ps=null; osoreo;V^
try{ hq6B
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conn = DBUtils.getConnection(); `TYQ^Zm
conn.setAutoCommit(false); 9TIyY`2!
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); mSp-
for(int i=0;i<CountCache.list.size();i++){ j 6%X
CountBean cb=(CountBean)CountCache.list.getFirst(); ug'I:#@2
CountCache.list.removeFirst(); WS/^WxRY
ps.setInt(1, cb.getCountId()); X,C&nqVFm8
ps.executeUpdate();⑴ 9c1g,:8\
//ps.addBatch();⑵ Wb+^Ue
} !
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//int [] counts = ps.executeBatch();⑶ ZR.1SA0x?O
conn.commit(); HJhPd#xCW
}catch(Exception e){ F[<EXLQ
e.printStackTrace(); L(\sO=t
} finally{ >@KQ )p' `
try{ X6kB
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if(ps!=null) { 'b:e`2fl
ps.clearParameters(); }S<2({GI
ps.close(); es]\xw
ps=null; {hG r`Rh
}
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}catch(SQLException e){} :y==O4
DBUtils.closeConnection(conn); @kvgq 0ab
} J]UlCg
} a/;u:"
public long getLast(){ '(mJ*Eb
return lastExecuteTime; S+py\z%
}
F' s($n
public void run(){ )SQ*"X4"
long now = System.currentTimeMillis(); 7F;"=DarOE
if ((now - lastExecuteTime) > executeSep) { /e1m1 B
//System.out.print("lastExecuteTime:"+lastExecuteTime); vo)pT
//System.out.print(" now:"+now+"\n"); X|K"p(N
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); et(/`
lastExecuteTime=now; 1@q~(1-o
executeUpdate(); 34-QgE
} #t:]a<3Y2
else{ F(>']D9$.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); s\i=-`
} :*gYzk8
} xx0s`5
} gvvl3`S{
//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 vZj^&/F$=g
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类写好了,下面是在JSP中如下调用。 J\<7M8
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<% #c@Dn.W
CountBean cb=new CountBean(); 8:;_MBt
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }$!bD
CountCache.add(cb); +N5#EpW
out.print(CountCache.list.size()+"<br>"); =A={Dpv[>
CountControl c=new CountControl(); [RCUP.
c.run(); lS]<~
out.print(CountCache.list.size()+"<br>"); WJ=DTON
%>