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: PlA#xnq#
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CountBean.java Wrp+B[{r\
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/* }u0&> k|y
* CountData.java +cmi?~KS*
* <GQ=PrT|/
* Created on 2007年1月1日, 下午4:44 gjnEN1T22
* u6l)s0Q
* To change this template, choose Tools | Options and locate the template under $[MAm)c:]{
* the Source Creation and Management node. Right-click the template and choose KOXG=P0
* Open. You can then make changes to the template in the Source Editor. 0~WXA=XG
*/ Bv3B|D&+
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package com.tot.count; b|kL*{;
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/** 2MYez>D
* xpuTh"ED
* @author eA?|X|
*/ ..'"kX:5
public class CountBean { eA
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private String countType; x]%,?Vd?
int countId; k6z]"[yu
/** Creates a new instance of CountData */ Zn)o@'{}{
public CountBean() {} -}oH],C
public void setCountType(String countTypes){ ]qq2VO<b
this.countType=countTypes; \' A-
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} j%]sym
public void setCountId(int countIds){ Rh
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this.countId=countIds; Qu8=zI>t
} if\`M'3Xx
public String getCountType(){ ){,Mv:#+T
return countType; *tR'K#:&g!
} 2dJE`XL
public int getCountId(){ Rx&.,gzj[
return countId; *L*{FnsV
} })(robBkA
} wCv9VvF`
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CountCache.java $*_79F2zN
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/* \{a5]G(4s
* CountCache.java ;tA$
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* I*cb\eU8Y
* Created on 2007年1月1日, 下午5:01 ]uh/ !\
* 7o!t/WEEq
* To change this template, choose Tools | Options and locate the template under I7Abf7>*Q
* the Source Creation and Management node. Right-click the template and choose 5t_Dt<lIz
* Open. You can then make changes to the template in the Source Editor. Rm$( X5x>o
*/ >nvK{6xR:
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package com.tot.count; vAeVQ~
import java.util.*; r_tt~|s,>
/** Jx`7W1%T
* +eLL)uk
* @author L
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*/ x6Gl|e[jv
public class CountCache { i$6a0'@U
public static LinkedList list=new LinkedList(); w6Mv%ZO_
/** Creates a new instance of CountCache */ TMsCl6dB
public CountCache() {} G6x'Myg I
public static void add(CountBean cb){ itiSZL,
if(cb!=null){ .~rg#*]^
list.add(cb); .i|nn[H &
} #(+V&<K
} -*J!Ws(9
} e?O$`lf
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CountControl.java -3b_}by
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/* eHd7fhW5
* CountThread.java '`W6U]7>
* U^)`_\/;?
* Created on 2007年1月1日, 下午4:57 10m|?
* [[';Hi^
* To change this template, choose Tools | Options and locate the template under -'*<;]P+.
* the Source Creation and Management node. Right-click the template and choose 01RW|rN
* Open. You can then make changes to the template in the Source Editor. "K+EZ%~<
*/ `@0AGSzUv
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package com.tot.count; 7;Q4k"h
import tot.db.DBUtils; ;3bUgI}.J
import java.sql.*; 3QdCu<eBZ
/** STg}
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* "i*gJFW|
* @author ;$4&Qp:#
*/ 2hryY
public class CountControl{ 7+X~i@#rU
private static long lastExecuteTime=0;//上次更新时间 |}<Gz+E>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AKk&
/** Creates a new instance of CountThread */ `YMd0*
public CountControl() {} SdnO#J}{
public synchronized void executeUpdate(){ GWWaH+F[h
Connection conn=null; H(M{hfa|
PreparedStatement ps=null; m"'`$ /_
try{ IAe/)
conn = DBUtils.getConnection(); qss)5a/x.
conn.setAutoCommit(false); YGc:84S
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); PQh s^D
for(int i=0;i<CountCache.list.size();i++){ !<~cjgdx
CountBean cb=(CountBean)CountCache.list.getFirst(); {5d 5Y%&
CountCache.list.removeFirst(); F>X<=YO0
ps.setInt(1, cb.getCountId()); pe3;pRh'
ps.executeUpdate();⑴ fl2XI=[v4
//ps.addBatch();⑵ Y
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} \W=
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//int [] counts = ps.executeBatch();⑶
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conn.commit(); N&Ho$,2s
}catch(Exception e){ )t\aB_ =
e.printStackTrace(); rQ U6*f
} finally{ %9S0!h\
try{ QH,(iX6RY
if(ps!=null) { o?a3hD
ps.clearParameters(); N0NFgW;
ps.close(); YB2gxZ
ps=null; %so{'rQl
} Qj(ppep\U"
}catch(SQLException e){} G\V*j$}!
DBUtils.closeConnection(conn); r}D#(G$
} Jo~fri([%Q
} ]bpgsW:Xu
public long getLast(){ yq^Ma
return lastExecuteTime; j4]3}t0q
} _z 5W*..
public void run(){ {0-rnSjC
long now = System.currentTimeMillis(); x)eoz2E1
if ((now - lastExecuteTime) > executeSep) { l~DIV$>,Z
//System.out.print("lastExecuteTime:"+lastExecuteTime); _jgtZ
//System.out.print(" now:"+now+"\n"); ``6-
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Nv6"c<(L=
lastExecuteTime=now; DGS,iRLnA
executeUpdate(); qE]e+S?57a
} $z 5kA9
else{ ;_E|I=%'E
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); %:;g|PC
} P*VZ$bUe5@
} G|8>Q3D
} QgQ$>
//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 YgS,5::SU
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类写好了,下面是在JSP中如下调用。 =_ b/g
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<% d2-oy5cEB
CountBean cb=new CountBean(); .V3e>8gw3
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); W}MN-0
CountCache.add(cb); UF*R1{
out.print(CountCache.list.size()+"<br>"); P~iZae
CountControl c=new CountControl(); jiLJiYMg
c.run(); "dvo@n|
out.print(CountCache.list.size()+"<br>"); hCd? Kti
%>