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: HFtf
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CountBean.java *^XbDg9
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/* lAASV{s{
* CountData.java %w"nDu2Gcv
* Fi;VDK(V9
* Created on 2007年1月1日, 下午4:44 ^Udv]Wh
* ?&c:q3_-Z
* To change this template, choose Tools | Options and locate the template under 1;r69e
* the Source Creation and Management node. Right-click the template and choose #MgvG,
* Open. You can then make changes to the template in the Source Editor. Vb4;-?s_
*/ f}fsoDoQ=
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package com.tot.count; S`q%ypy
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/** Nw<P
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* SN">gmY+
* @author vA&Vu"}S
*/ ;5S}~+j
public class CountBean { \C|cp|A*&
private String countType; lpC
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int countId; &=q! Wdw~
/** Creates a new instance of CountData */ 9`Q@'(m
public CountBean() {} IB$7`7
public void setCountType(String countTypes){ jj&s}_75
this.countType=countTypes; tJZc/]%`H
} d/U."V}
public void setCountId(int countIds){ fC<m^%*zgA
this.countId=countIds; z@h~Vb&I
} s3 QEi^~
public String getCountType(){ "^rNr_
return countType; wyY*:{lZ
} !~ rt:Z
public int getCountId(){ 4u1KF:g
return countId; isK;mU?<
} ~L?nq@DL
} QZYU0;
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CountCache.java zK5bO=0j
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/* }C#3O{5
* CountCache.java oyeG$mpg
* YD_]!HK}
* Created on 2007年1月1日, 下午5:01 AFm1t2,+;
* Y
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* To change this template, choose Tools | Options and locate the template under uHM@h{r
* the Source Creation and Management node. Right-click the template and choose >L>+2z
* Open. You can then make changes to the template in the Source Editor. D3]BTkMMS;
*/ Sp?NfJ\Ie
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package com.tot.count; m4/er539T
import java.util.*; Z85|I.mr
/** 0|Ucd
* $99R| ^
* @author ?d-70pm
*/ w]!0<
public class CountCache { R}{GwbF_\
public static LinkedList list=new LinkedList(); 0i@:KYP
/** Creates a new instance of CountCache */ ><Z'D
public CountCache() {} %xlpB75N4N
public static void add(CountBean cb){ 1y[B[\
if(cb!=null){ HOPqxI(k
list.add(cb); !:
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} CZ=0mWfF
} Z9
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} Pl
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CountControl.java C1B'#F9EO
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/* TQ'E5^
* CountThread.java S@}4-\
* r6Nm!Bq7
* Created on 2007年1月1日, 下午4:57 r"_Y3SxxL
* l5J.A@0
* To change this template, choose Tools | Options and locate the template under 8LrK94
* the Source Creation and Management node. Right-click the template and choose `wO}Hz
* Open. You can then make changes to the template in the Source Editor. 7
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*/ v59nw]'
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package com.tot.count; }~I|t!GL
import tot.db.DBUtils; &Ocu#Cb
import java.sql.*; J!p<oW)a!
/** 0HibY[_PbD
* BQNp$]5s
* @author u{C)qb5Pu
*/ uHvaZMu
public class CountControl{ bZ5n,KQA5
private static long lastExecuteTime=0;//上次更新时间 MCy~@)-IN
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 XB/'u39
/** Creates a new instance of CountThread */ 2P}bG>M
public CountControl() {} U^$E'Q-VK
public synchronized void executeUpdate(){ -2*>`,Uu
Connection conn=null; ;z>p8N
PreparedStatement ps=null; &]NZvqdj.]
try{ 36A;!1
conn = DBUtils.getConnection(); EXbTCT}`x
conn.setAutoCommit(false); p\D >z("
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 5~}!@yzc
for(int i=0;i<CountCache.list.size();i++){ nNR:cGfG
CountBean cb=(CountBean)CountCache.list.getFirst(); 3M
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CountCache.list.removeFirst(); 8hB.fau
ps.setInt(1, cb.getCountId()); 80&D""
ps.executeUpdate();⑴ nVOqn\m-
//ps.addBatch();⑵ v33T @
} J(9=T<%T
//int [] counts = ps.executeBatch();⑶ p_6P`Yx^e
conn.commit(); A*0*sZ0
}catch(Exception e){ {ymb\$f
e.printStackTrace(); r{ @ `o@q
} finally{ (%DRt4u<H
try{ =K'L|QKF
if(ps!=null) { s[V`e2O
ps.clearParameters(); vLn> 4SK
ps.close(); <\DUo0]J
ps=null; GOr}/y;
} VGJDqm!
}catch(SQLException e){} _rjBc;a
DBUtils.closeConnection(conn); %b<%w
} Zi1YZxF`Y
} !5.v'K'
public long getLast(){ ;=p;v .l
return lastExecuteTime; WZ*&@|w
} Sx&mv.?X
public void run(){ JQT4N[rEE
long now = System.currentTimeMillis(); }x0Z(
`
if ((now - lastExecuteTime) > executeSep) { sU%"azc
//System.out.print("lastExecuteTime:"+lastExecuteTime); eH[y[~r
//System.out.print(" now:"+now+"\n"); d*9j77C ]
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); b|wWHNEdb,
lastExecuteTime=now; e"_"vbk
executeUpdate(); 9 z*(8d
} zJ_My&~
else{ ]h8/M7k
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); L>:FGNf^H
} jt%WPkY:
} (`mOB6j
} Pz
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//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 7'UWRRsxUF
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类写好了,下面是在JSP中如下调用。 Q)dT(Td9~
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<% ~UW{)]_jox
CountBean cb=new CountBean(); 8Mb$+^zU
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); OR~G Ov|
CountCache.add(cb); C$y fMK,,N
out.print(CountCache.list.size()+"<br>"); G5+]DogS
CountControl c=new CountControl(); 4#@0T"T~M
c.run(); !F,s"
out.print(CountCache.list.size()+"<br>"); opnkmM&[
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