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: nYSe0w
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CountBean.java l7g'z'G
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/* \2kLj2!
* CountData.java {.2\}7.c
*
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* Created on 2007年1月1日, 下午4:44 2VRGTx
* R%KF/1;/
* To change this template, choose Tools | Options and locate the template under c*r H^Nz
* the Source Creation and Management node. Right-click the template and choose di/QJrw
* Open. You can then make changes to the template in the Source Editor. &jqylX
*/ PcC@}3
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package com.tot.count; >eA@s}_8
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/** %[|^7
* &:l-;7d
* @author `rVru= zoy
*/ kBZ1)?
public class CountBean { Q3WI@4
private String countType; zjA]Tr
int countId; ]qqgEZ1!Y
/** Creates a new instance of CountData */ rnZ$Qk-H
public CountBean() {} aqEZhMy
public void setCountType(String countTypes){ fk,Vry
this.countType=countTypes; b=r 3WkB6
} X8ulaa
public void setCountId(int countIds){ d#E&,^@M
this.countId=countIds; }gQ2\6o2g
} Rq}lW.<r
public String getCountType(){ {3x>kRaKci
return countType; l
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} Nbr$G=U
public int getCountId(){ 4fsd5#
return countId; bVzi^R"
} Y5tyFi#w[
} R`<^/h
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CountCache.java srf}+>u&
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/* RKP,w%
* CountCache.java J[<Zy^"Y;
* 5csh8i'V
* Created on 2007年1月1日, 下午5:01 O?X[&t
* +7b8 ye
* To change this template, choose Tools | Options and locate the template under _nqnO8^IG4
* the Source Creation and Management node. Right-click the template and choose ?zBu`7j
* Open. You can then make changes to the template in the Source Editor. c9nR&m8(+
*/ 'O(=Pz
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package com.tot.count; wNHn.
import java.util.*; Fs~(>w@
/** 83c2y;|8
* QP%_2m>yhl
* @author r+ bGZ
*/ -~{Z*1`,
public class CountCache { O#U maNj/
public static LinkedList list=new LinkedList(); ."+lij=56
/** Creates a new instance of CountCache */ ~gpxK{
public CountCache() {} Kd-1EU
public static void add(CountBean cb){ ) bFl-
if(cb!=null){ yus3GqPI
list.add(cb); a6LL]_&g
} n- 2X?<_Z
} >IIq_6Z#
} OL
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CountControl.java bKpy?5&>
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/* cp@Fj"
* CountThread.java 2Xl+}M.:Y
* j+h+Y|4J
* Created on 2007年1月1日, 下午4:57 hty'L61\z
* fLe~X!#HF
* To change this template, choose Tools | Options and locate the template under ZoXz@/T
* the Source Creation and Management node. Right-click the template and choose n>}Y@{<]/
* Open. You can then make changes to the template in the Source Editor. `r}_92Tt
*/ fc+-/!v
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package com.tot.count; zhw*Bed<
import tot.db.DBUtils; ts~VO`
import java.sql.*; {\(G^B*\
/** C*2%Ix18+N
*
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* @author !Axe}RD'
*/ !}!KT(%%
public class CountControl{ :C_/K(Rkl
private static long lastExecuteTime=0;//上次更新时间 y5sH7`2+5
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 zgGysjV
/** Creates a new instance of CountThread */ 9F807G\4Qt
public CountControl() {} T!H(Y4A
public synchronized void executeUpdate(){ } [#8>T
Connection conn=null; NIQ}A-b
PreparedStatement ps=null; sa8O<Ab
try{ */e$S[5
conn = DBUtils.getConnection(); "0!h-bQN
conn.setAutoCommit(false); yF)J7a:U
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); zjUQ]
for(int i=0;i<CountCache.list.size();i++){ Gt&yz"?D
CountBean cb=(CountBean)CountCache.list.getFirst(); %"f85VfZ
CountCache.list.removeFirst(); 9Q1%+zjjMq
ps.setInt(1, cb.getCountId()); sg,\!'
ps.executeUpdate();⑴ ` &A`&-nc=
//ps.addBatch();⑵ ,w~3K%B4
} 50MM05aC
//int [] counts = ps.executeBatch();⑶ Tm`@5
conn.commit(); rT `sY
}catch(Exception e){ xq;>||B
e.printStackTrace(); >2s6Y
} finally{ :=B.)]F.)
try{ E.*hY+kGZ
if(ps!=null) { vt5w(}v(
ps.clearParameters(); wG)e8,#
ps.close(); a
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ps=null; %d+Fq=<
} oSrA4g
}catch(SQLException e){} fZ-"._9UyH
DBUtils.closeConnection(conn); %$ya>0?mq
} N 8[rWJ#
} X}Q4;='C-
public long getLast(){ g}hUCx(
return lastExecuteTime; 1#x5
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} %O9 Wm_%
public void run(){ ~S('\h)1
long now = System.currentTimeMillis(); ^Z)7Z%
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if ((now - lastExecuteTime) > executeSep) { *R+M#l9D`
//System.out.print("lastExecuteTime:"+lastExecuteTime); 1<vJuF^
//System.out.print(" now:"+now+"\n"); wxHd^b
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); m^oG9&";
lastExecuteTime=now; LhAN( [
executeUpdate(); 1vq2`lWpx
} 9C \}bT
else{ ]lA}5
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2@MpWj4
} rS>.!DiYr,
} MX]#|hEeQ
} Lz1KDXr`)+
//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 _t-6m2A
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类写好了,下面是在JSP中如下调用。 P1OYS\
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<% !!L'{beF
CountBean cb=new CountBean(); 6|p8_[e`
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); jlb8<xIC]
CountCache.add(cb); _i ztQ78
out.print(CountCache.list.size()+"<br>"); $@6q5Iz!&
CountControl c=new CountControl(); ( 72%au
c.run(); U)'YR$2<
out.print(CountCache.list.size()+"<br>"); R>"pJbS;L
%>