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: +~~FfIzf#
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CountBean.java I*cB
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/*
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* CountData.java >C,=elM
* QC@nRy8%
* Created on 2007年1月1日, 下午4:44 hAx#5@*5
* 3^p<Wx
* To change this template, choose Tools | Options and locate the template under /C)mx#h]
* the Source Creation and Management node. Right-click the template and choose bvdAOvxChW
* Open. You can then make changes to the template in the Source Editor. pqmb&"l
*/ .b'o}DLa
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package com.tot.count; cQ kH4>C~
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/** TAfLC)
* ul0]\(sS:
* @author MbY?4i00%h
*/ AgKG>%0
public class CountBean { JMp>)*YS
private String countType; ["4sCB@Tr
int countId; 5 9$B
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/** Creates a new instance of CountData */ #H9J/k_
public CountBean() {} !63>I I
public void setCountType(String countTypes){ Z"spua5
this.countType=countTypes; tbz?th\#
} OsS5WY0H
public void setCountId(int countIds){ j2GO ZKy
this.countId=countIds; J:6wFmU
} bb<qnB
public String getCountType(){ _86pbr9
return countType; ,S"a ,}8
} PF$K> d
public int getCountId(){ ;O7CahdF
return countId; EPx_xX
} 5?-cP?|.9
} }bj
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CountCache.java 6=ukR=]v
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/* A2Je*Gz
* CountCache.java 29:1crzx~
* ` fw:
* Created on 2007年1月1日, 下午5:01 );4lM%]eb
* r>v_NKS]t
* To change this template, choose Tools | Options and locate the template under $dr=M(&
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. Fa
*/ 34Q;& z\e
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package com.tot.count; `[T|Ck5
import java.util.*; N}ur0 'J0
/** V6)e Jy
* bWc3a
* @author pqaQ% |<
*/ ]Z/<HP$#
public class CountCache { z#qlu=
public static LinkedList list=new LinkedList(); \i
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/** Creates a new instance of CountCache */ M%dJqwH5{
public CountCache() {} B> kx$_~
public static void add(CountBean cb){ =,Yi" E
if(cb!=null){ Pba 6Ay6B
list.add(cb); J*)Vpk
} CiE
} h-0sDt pR
} CD$0Z
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CountControl.java sT|$@$bN
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/* 3GEI) !
* CountThread.java v7rEUS-
* t*<@>] k
* Created on 2007年1月1日, 下午4:57 DDdMWH^o7
* hrfu\cI
* To change this template, choose Tools | Options and locate the template under 9 *>@s
* the Source Creation and Management node. Right-click the template and choose *E"QFirk0
* Open. You can then make changes to the template in the Source Editor. z[kz[
*/ sZ`C
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@ 2r9JqR[=
package com.tot.count; j$%KKl8j
import tot.db.DBUtils; aA Hx^X^
import java.sql.*; W,</
/** U\N|hw#f!!
* oj.f
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* @author D
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*/ IooAXwOF
public class CountControl{ 3*@ sp
private static long lastExecuteTime=0;//上次更新时间 #{973~uj
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Xg>nb1e
/** Creates a new instance of CountThread */ R"Q=U}?$
public CountControl() {} p|mt2oDjw
public synchronized void executeUpdate(){ <0my,hAK
Connection conn=null; ,xA`Fu9^
PreparedStatement ps=null; 3QL I|VpO
try{ 9NCo0!Fb
conn = DBUtils.getConnection(); 2z/qbzG7
conn.setAutoCommit(false); plL##?<D<
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); RS&l68[6
for(int i=0;i<CountCache.list.size();i++){ g'G"`)~ 2
CountBean cb=(CountBean)CountCache.list.getFirst(); x1['+!01
CountCache.list.removeFirst(); HX1RA5O
ps.setInt(1, cb.getCountId()); w6C0]vh
ps.executeUpdate();⑴ :S
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//ps.addBatch();⑵ B+:'Ld](
} \B _g=K
//int [] counts = ps.executeBatch();⑶ JA!O,4
conn.commit(); U
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}catch(Exception e){ n W2[x;
e.printStackTrace(); u<`CkYT
} finally{ ?C#=Q6
try{ ;B[*f?y-
if(ps!=null) { YVy+1q[
ps.clearParameters(); [}s nKogp
ps.close(); kh3PEq
ps=null; xL,;(F\^
} PprCz"
}catch(SQLException e){} 98u$5=Z'/
DBUtils.closeConnection(conn); OhT?W[4
} O][R"5d
} =]r<xON%S
public long getLast(){ STMc@MeZU_
return lastExecuteTime; ?nOul}y/
} --SlxV/x
public void run(){ n6T@A;_g
long now = System.currentTimeMillis(); iU^KmM I
if ((now - lastExecuteTime) > executeSep) { DgOO\
//System.out.print("lastExecuteTime:"+lastExecuteTime); b/N+X}VMN
//System.out.print(" now:"+now+"\n"); 'F[m,[T%x
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); %";bgU2Q
lastExecuteTime=now; `TvpKS5.Y
executeUpdate(); I$@0FSl
} Y*-#yG9
else{ SH#-3&$[
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); JTuU}nm+
} {"<D$*K~
} $bQ[H[4l
} @d imZsi1
//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 w}="}Cb
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类写好了,下面是在JSP中如下调用。 +an.z3?w
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<% Q[t|+RNKv2
CountBean cb=new CountBean(); Bny3j~*U
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :f?};t+
CountCache.add(cb); m
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out.print(CountCache.list.size()+"<br>"); @ToY,@]e
CountControl c=new CountControl(); $q`650&S*
c.run(); E"p;
out.print(CountCache.list.size()+"<br>"); 9&R. <I
%>