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: 4nVO.Ud0$X
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CountBean.java -7C=- \]
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/* hs -}:^S`
* CountData.java 3!ajvSOI9j
* bOnukbJ
* Created on 2007年1月1日, 下午4:44 iG;d0>Sp
* 9I^H)~S
* To change this template, choose Tools | Options and locate the template under S%a}ip&
* the Source Creation and Management node. Right-click the template and choose 9v5.4a}
* Open. You can then make changes to the template in the Source Editor. x r+E
*/ A7I8Z6&
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package com.tot.count; U3VsMV*Y
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/** //4p1^%
* `"bRjC"f]
* @author B4M'Er{v
*/ EP%
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public class CountBean { Bt`r6v;\
private String countType; /M{)k_V
int countId; 7\Yq]:;O
/** Creates a new instance of CountData */ &`\kb2uep
public CountBean() {} l#J>It\
public void setCountType(String countTypes){ $D2Ain1
this.countType=countTypes; *(XgUJq+
} c+\Gd}IJq
public void setCountId(int countIds){ [3bwbfHhi
this.countId=countIds; ~k:>Xo[|O
} =-a?oH-
public String getCountType(){ y+~Aw"J}
return countType; +$pO
} O+3D
5*
public int getCountId(){ (t"YoWA#m
return countId; PHB\)/
} *<
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} N]<~NG:6b
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CountCache.java oeU+?-y/b
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/* G@l|u
* CountCache.java vr]dRStr
* 6b1 Uj<
* Created on 2007年1月1日, 下午5:01 "}azC|:5
* R}=]UOqH-
* To change this template, choose Tools | Options and locate the template under m<VL19o>R
* the Source Creation and Management node. Right-click the template and choose B+e~k?O] 1
* Open. You can then make changes to the template in the Source Editor. xX67bswG
*/ WY ^K7U
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package com.tot.count; _ZvX" {y~
import java.util.*; 9DocId.
/** h?O%XnD
* }e;p8)]Wl
* @author nh_xbo5L[
*/ 70 DQ/b
public class CountCache { j(2tbWg9-
public static LinkedList list=new LinkedList(); oU{-B$w
/** Creates a new instance of CountCache */ 8i+jFSZ$
public CountCache() {} C ^ k3* N
public static void add(CountBean cb){ v(WL 3[y;
if(cb!=null){ #xE>]U
list.add(cb); s9)8{z
} hrtN.4p[
} I[YfF
} )-7(Hv1
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CountControl.java DyV[+P
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/* TTjjyZ@
* CountThread.java )}k`X<~k
* >?Y3WPB<F
* Created on 2007年1月1日, 下午4:57 !-Tmu
* W71#NjM2Z
* To change this template, choose Tools | Options and locate the template under [O =)FiY-
* the Source Creation and Management node. Right-click the template and choose Ql!6I (
* Open. You can then make changes to the template in the Source Editor. eXtF[0f
*/ ~s^6Q#Z9|
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package com.tot.count; 1</t #r
import tot.db.DBUtils; Zi '8~iEH
import java.sql.*; P<w>1
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/** E9NGdp&-Ah
* Nl>b'G96
* @author 7B> cmi
*/ pLFL6\{g
public class CountControl{ @;-Un/'C;7
private static long lastExecuteTime=0;//上次更新时间 b+fy&rk@-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 >Sl:Z ,g;
/** Creates a new instance of CountThread */ Sv[_BP\^h
public CountControl() {} XcW3IO
public synchronized void executeUpdate(){ Op)R3qt{
Connection conn=null; "B{xC}Tw
PreparedStatement ps=null; P)
0=@{(
try{ (:hmp"S
conn = DBUtils.getConnection(); KLM^O$=
conn.setAutoCommit(false); I2!&=" 7@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); pPqbD}p
for(int i=0;i<CountCache.list.size();i++){ hB1 iSm
CountBean cb=(CountBean)CountCache.list.getFirst(); 5nlyb,"^g
CountCache.list.removeFirst(); "Kf~`0P
ps.setInt(1, cb.getCountId()); BB}iBf I'
ps.executeUpdate();⑴ s#CEhb
//ps.addBatch();⑵ !haXO
} 5|H(N}S_
//int [] counts = ps.executeBatch();⑶ t@mw f3,
conn.commit(); 5+PBS)pJ]%
}catch(Exception e){ /VOST^z!
e.printStackTrace(); RAJ|#I1
} finally{ ~V)VGGOL$v
try{ mCP +7q7
if(ps!=null) { +(hwe
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ps.clearParameters(); sjbC~Te--
ps.close(); eT
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ps=null; olW`.3f
} _p^ "!
}catch(SQLException e){} P<oD*C
DBUtils.closeConnection(conn); g{.@|;d<p
} <\Dl#DH
} 8c'-eT"
public long getLast(){ U\plt%2m>
return lastExecuteTime; s.Ic3ITd,
} 15yV4wHr
public void run(){ F973U
long now = System.currentTimeMillis(); <qZ+U4@I)
if ((now - lastExecuteTime) > executeSep) { "U~@o4u;
//System.out.print("lastExecuteTime:"+lastExecuteTime); ymJw{&^am
//System.out.print(" now:"+now+"\n"); &dMSX}t
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Z#t.wWSq
lastExecuteTime=now; E<[
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executeUpdate(); Hm[!R:HW,S
} eyp\h8!u_
else{ @Pg@ltUd
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); #8HXR3L5=!
} gG?*Fi
} Or~6t}f
} :l[Q
//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 U-N/Z\QD
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类写好了,下面是在JSP中如下调用。 Ol^EQLO
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<% QE6-(/
CountBean cb=new CountBean(); --hnv/AjI
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ?a_q!,8:
CountCache.add(cb); DFH6.0UW
out.print(CountCache.list.size()+"<br>"); (9lx5
CountControl c=new CountControl(); gDBQ\vM8
c.run(); > %*X2'^
out.print(CountCache.list.size()+"<br>"); y.NArN|%
%>