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: @UidQX"b
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CountBean.java Yi+~}YP.E(
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/* /4Lmu+G4
* CountData.java ?nAKB5=
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* Created on 2007年1月1日, 下午4:44 >av.pJ(>
* K2GcU_*t
* To change this template, choose Tools | Options and locate the template under H^no&$2`1
* the Source Creation and Management node. Right-click the template and choose GxIw4m9
* Open. You can then make changes to the template in the Source Editor. sB,>4*Zd
*/ 9k@`{+wmZ
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package com.tot.count; g$f;
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/** $q6'VLPo
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* @author Kc:}
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*/ dn1Tu6f;|
public class CountBean { pH1 9"=p<
private String countType; 20t</lq.
int countId; /:}z*a
/** Creates a new instance of CountData */ ohA@Zm8O
public CountBean() {} c.\J_^
public void setCountType(String countTypes){ fii\&p7z
this.countType=countTypes;
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} F^]?'`7md
public void setCountId(int countIds){ cs%NsnZ
this.countId=countIds; '0xJp|[xVP
} z4nVsgQ$
public String getCountType(){ !r8Jo{(pb
return countType; KrFV4J[
} A<&:-Zz
public int getCountId(){ D?w-uR%Y
return countId; drQioH-
} d[9NNm*htC
} (1vmtg.O
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CountCache.java X; gN[
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/* [i '\d}
* CountCache.java DvuL1MeKo
* Z0~}'K
* Created on 2007年1月1日, 下午5:01 @Yq!
* B`4[@$
* To change this template, choose Tools | Options and locate the template under %-4e8d74/
* the Source Creation and Management node. Right-click the template and choose sKX%<n$
* Open. You can then make changes to the template in the Source Editor. S"=oU}'|
*/ eXU;UO^
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package com.tot.count; YJ5;a\QxN
import java.util.*; ~%Ws"1
/** Kup-O
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* @author L?^C\g6u]
*/ 8<g_JW[%
public class CountCache { C%P"Ds=w0N
public static LinkedList list=new LinkedList(); hfvs'.
/** Creates a new instance of CountCache */ e;=G|E
public CountCache() {} b* 6c.
public static void add(CountBean cb){ NRKAEf_#w
if(cb!=null){ ;D/'7f7.}
list.add(cb); t3/!esay
} omV.Qb'NS
} Dz&4za+{
} b)u9#%Q
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CountControl.java <C4^Vem
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/* q\[31$i$
* CountThread.java w9}I*Nra
* Y54*mn
* Created on 2007年1月1日, 下午4:57 v]*W*;
* uF T\a=
* To change this template, choose Tools | Options and locate the template under $ZDh8
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* the Source Creation and Management node. Right-click the template and choose ,>(M5\Z/c
* Open. You can then make changes to the template in the Source Editor. H[x 9 7r
*/ T^GdN_qF
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package com.tot.count; .)Se-'
import tot.db.DBUtils; r _r$nl
import java.sql.*; n X
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/** ej<z]{`05
* Smk]G))o{
* @author :;"3k64
*/ 6x@-<{L
public class CountControl{ 1&YP}sg)
private static long lastExecuteTime=0;//上次更新时间 cf@#a@7m9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 qRB7I:m-Wi
/** Creates a new instance of CountThread */ vfhip"1
public CountControl() {} Qb# S)[6s+
public synchronized void executeUpdate(){ V!KtF
Connection conn=null; y&__2t^u
PreparedStatement ps=null; "_)
try{ XB;;OP12
conn = DBUtils.getConnection(); 4r(rWlM
conn.setAutoCommit(false); Zt` ,DM
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); xs &vgel>
for(int i=0;i<CountCache.list.size();i++){ ,75,~
CountBean cb=(CountBean)CountCache.list.getFirst(); l!i B
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CountCache.list.removeFirst(); kd\yHI9A
ps.setInt(1, cb.getCountId()); Mdwh-Cis/
ps.executeUpdate();⑴ !s)2H/KM 8
//ps.addBatch();⑵ $]81 s`
} &8&WY1cU
//int [] counts = ps.executeBatch();⑶ NHc+QMbou(
conn.commit(); 6-X7C9`C
}catch(Exception e){ N&>D/Z;"
e.printStackTrace(); QW2% Gv:
} finally{ \iVYhl
try{ 1<R
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if(ps!=null) { w\t{'
ps.clearParameters(); tOko %vY8
ps.close(); <1jiU%!w
ps=null; 2N,*S
} M(3E
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}catch(SQLException e){} 6
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DBUtils.closeConnection(conn); % 9WWBxS
} *`jEg=)
} ZRxB" a'
public long getLast(){ i&LbSxUh9
return lastExecuteTime; r?V|9B`$p
} mU&J,C
public void run(){ qbAoab53
long now = System.currentTimeMillis(); alu`T
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if ((now - lastExecuteTime) > executeSep) { /|DQ_<*
//System.out.print("lastExecuteTime:"+lastExecuteTime); <g %xo"
//System.out.print(" now:"+now+"\n"); ;%82Z4
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); d#z67Nl6
lastExecuteTime=now; "{0kg'fU
executeUpdate(); 3S5QqAm
} /r?X33D!
else{ E{Q^ZSV3B
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ZK'I$p]b
} 03#_ (
} yz+r@I5
} ?)PcYrV
//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 uw<Ruy
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类写好了,下面是在JSP中如下调用。 Y.C*|p#
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<% ):[[Ch_
CountBean cb=new CountBean(); $Y4
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); TM RXl.1
CountCache.add(cb); G![1+2p:Tq
out.print(CountCache.list.size()+"<br>"); \m.{^Xd~
CountControl c=new CountControl(); 0bd.ess
c.run(); 0s4j>
out.print(CountCache.list.size()+"<br>"); ?D~uR2+Z
%>