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: c:? tn
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CountBean.java DAYR=s
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/* -lICoRO#
* CountData.java vlW521
* rf@Cz%xDD
* Created on 2007年1月1日, 下午4:44 C1/qiSHsh
* w4I&SLm-b
* To change this template, choose Tools | Options and locate the template under bxU 2.YC
* the Source Creation and Management node. Right-click the template and choose e3T&KyPm?+
* Open. You can then make changes to the template in the Source Editor. 5D9n>K4|
*/ yE+Wb[H[
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package com.tot.count; ^LAP*R
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/** o;w5;TkY
* !Q/oj
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* @author MK1V1F`
*/ )I&,kH)+
public class CountBean { YCMXF#1
private String countType; ;iB9\p$K)
int countId; 4\?z^^
/** Creates a new instance of CountData */
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public CountBean() {} b({K6#?'[
public void setCountType(String countTypes){ S1d^mu
this.countType=countTypes; 8/i];/,v*M
} goa@e
public void setCountId(int countIds){ w?;j5[j
this.countId=countIds; Hsdcv~Xr;l
} kD}w5 U
public String getCountType(){ ZwzN=03T
return countType; Dt#( fuk#
} *P:!lO\|
public int getCountId(){
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return countId; 4fR}+[~2
} 5)@UpcjUA
} =qWcw7!"
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CountCache.java ./7*<W:
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/* [{&GMc
* CountCache.java Fy6(N{hql
* -e2f8PV?3
* Created on 2007年1月1日, 下午5:01 L<QjkFj
* e9\eh? bPU
* To change this template, choose Tools | Options and locate the template under PH1jN?OEwZ
* the Source Creation and Management node. Right-click the template and choose *(+*tjcWa
* Open. You can then make changes to the template in the Source Editor. v ?Ds|
*/ vz~`M9^
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package com.tot.count; Y|
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import java.util.*; 4lp90sa
/** D*_Z"q_B
* &eA!h
* @author r*F^8_YMK
*/ +sY8<y@%
public class CountCache { 6 d;_}
public static LinkedList list=new LinkedList(); 4{v?<x8
/** Creates a new instance of CountCache */ 6?`3zdOeO
public CountCache() {} O-3R#sZ0
public static void add(CountBean cb){ )i^+=TZ q
if(cb!=null){ Jc=~BT_G
list.add(cb); vB?(|
} v?@=WG
} Zws[C
}
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CountControl.java 0F5QAR
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/* -J&
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* CountThread.java W Te1E, M
* AqZ()p*z
* Created on 2007年1月1日, 下午4:57 )x<oRHx]
* hy}n&h
* To change this template, choose Tools | Options and locate the template under n/ CP2A
* the Source Creation and Management node. Right-click the template and choose SHA6;y+U/~
* Open. You can then make changes to the template in the Source Editor. [QZ8M@Gty#
*/ p=T6Ix'_2e
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package com.tot.count; IW>\\&pJ
import tot.db.DBUtils; 8ioxb`U
import java.sql.*; Ib}~Q@?2
/** IM(=j
* D:56>%y@
* @author _(_U=
*/ Q2LAXTF]y
public class CountControl{ .
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private static long lastExecuteTime=0;//上次更新时间 {P7 I<^,
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 _8{6&AmIw
/** Creates a new instance of CountThread */ gyT3[*eh
public CountControl() {} .a_xQ]eQ
public synchronized void executeUpdate(){ IKFNu9*"h
Connection conn=null; lxh}N,
PreparedStatement ps=null; _|C T|q
try{ IAFj_VWC0
conn = DBUtils.getConnection(); "t>WM
conn.setAutoCommit(false); +'`I]K>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $=ua$R4Z+
for(int i=0;i<CountCache.list.size();i++){ jQX9KwSP
CountBean cb=(CountBean)CountCache.list.getFirst(); Egm-PoPe
CountCache.list.removeFirst(); d-ML[^G
ps.setInt(1, cb.getCountId()); Fu*Qci1Z
ps.executeUpdate();⑴ E/Adi^
//ps.addBatch();⑵ /zTx+U.\I
} oFDJwOJ'Bj
//int [] counts = ps.executeBatch();⑶ /8[T2Z!
conn.commit(); xN>+!&3%w
}catch(Exception e){ |Qz"Z<sNYw
e.printStackTrace(); _OY<Hb3%M
} finally{ BnPL>11Y
try{ T,uVt^.R+
if(ps!=null) { IuOQX}
ps.clearParameters(); FV>xAU$
ps.close(); 15Vo_
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ps=null; 'Im&&uSkr
} Epm%/ {sHV
}catch(SQLException e){} &B@qb?UE1
DBUtils.closeConnection(conn); W:y'a3~
} wpepi8w,
} $E35W=~)
public long getLast(){ <xaB$}R
return lastExecuteTime; ,&aD
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} Q^|aix~ K
public void run(){ f'&
long now = System.currentTimeMillis(); lFc4| _c g
if ((now - lastExecuteTime) > executeSep) { pWN5 >HV
//System.out.print("lastExecuteTime:"+lastExecuteTime); L.$+W}
//System.out.print(" now:"+now+"\n"); kT,2eel
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); -z?O^:e#x
lastExecuteTime=now; _/RP3" #
executeUpdate(); e*/ya 8p?
} G}0fk]%\:
else{ mP+rPDGp
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); kOLS<>.
} qp`G5bw
} 9
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} Sp~gY]:
//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 2\L}Ka|v
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类写好了,下面是在JSP中如下调用。 h@D</2>
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<% xyaU!E*
CountBean cb=new CountBean(); SO}en[()O
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Z<~^(W7h
CountCache.add(cb); Nbm=;FHB`
out.print(CountCache.list.size()+"<br>"); c[E>2P2-_
CountControl c=new CountControl(); F<^93a9
c.run(); %
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out.print(CountCache.list.size()+"<br>"); h|
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%>