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: /JkC+7H4
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CountBean.java RQB
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/* "vZ!vt#'Y
* CountData.java Qnd5X`jF#
* RsJ6OFcWV
* Created on 2007年1月1日, 下午4:44 D B E4&
* ^Yj xeNY
* To change this template, choose Tools | Options and locate the template under Bun><Y
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* the Source Creation and Management node. Right-click the template and choose 5L,}e<S$
* Open. You can then make changes to the template in the Source Editor. sarq`%zrk
*/ Xx:F)A8O
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package com.tot.count; -Go 7"j
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/** L|@y&di
* qqrq11W
* @author ma'FRt
*/ !V2/A1?
public class CountBean { MY#
private String countType; B=8Iu5m
int countId; UFAL1c<V
/** Creates a new instance of CountData */ Xce0~\_A
public CountBean() {} >K9#3
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public void setCountType(String countTypes){ mE%$HZ}
this.countType=countTypes; _j?e~w&0b
} _WX tB#
public void setCountId(int countIds){ a]
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this.countId=countIds; jO*l3:!~ \
} %wcSM~w
public String getCountType(){ :+Om]#`Vls
return countType; } :=Tm]S
} `K~AhlJUQ
public int getCountId(){ &e-U5'(6v_
return countId; r%:+$aIt
} h\v'9
} 1$qh`<\
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CountCache.java D%6;^^WyUx
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/* g<{xC_J
* CountCache.java HK|ynBAo
* $`R6=\|
* Created on 2007年1月1日, 下午5:01 Um#Wu]i
* PxH72hBS
* To change this template, choose Tools | Options and locate the template under D?XM,l+
* the Source Creation and Management node. Right-click the template and choose tyaA\F57
* Open. You can then make changes to the template in the Source Editor. FFdBtB
*/ b4^`DHRu6
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package com.tot.count; E|'h]NY
import java.util.*; m3Il3ZY.
/** @2'Mt}R>
* [kE."#
* @author 7i&:DePM'q
*/ !,V{zTR
public class CountCache { 5waKI?4F
public static LinkedList list=new LinkedList(); "HE^v_p
/** Creates a new instance of CountCache */ \]$IDt(s
public CountCache() {} _uc
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public static void add(CountBean cb){ Xd^\@
if(cb!=null){ .{y
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list.add(cb); KM^ufF2[
} y~()|L[
} ME'|saP
} _6ay-u
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CountControl.java 6 G=j6gK%P
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/* xhcK~5C
* CountThread.java ZXm/A0)S
* 4:g R r
* Created on 2007年1月1日, 下午4:57 0}_[DAd6
* giz7{Ai
* To change this template, choose Tools | Options and locate the template under gz3pX#S
* the Source Creation and Management node. Right-click the template and choose x c{hC4^V
* Open. You can then make changes to the template in the Source Editor. x?&$ ci
*/ ,}K<*t[I
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package com.tot.count; bw\@W{a%q
import tot.db.DBUtils; O)vp~@|
import java.sql.*; b0oMs=uBn
/** C*P7-oE2rh
* B(M6@1m_
* @author ..rOsg{
*/ 0jEL<TgC
public class CountControl{ n=[/Z!
private static long lastExecuteTime=0;//上次更新时间 Yk=PS[f
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 KEWTBBg
/** Creates a new instance of CountThread */ >,td(= :
public CountControl() {} qgfi\/$6
public synchronized void executeUpdate(){ o"*AtGR+"
Connection conn=null; 812$`5l
PreparedStatement ps=null; =ZqT3_
try{ G;YrF)\
conn = DBUtils.getConnection(); ti#7(^j
conn.setAutoCommit(false); -\C!I
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); i-6Z"b{
for(int i=0;i<CountCache.list.size();i++){ 2k=#om19
CountBean cb=(CountBean)CountCache.list.getFirst(); Qjb:WC7he
CountCache.list.removeFirst(); .0es3Rj
ps.setInt(1, cb.getCountId()); )==Jfn y
ps.executeUpdate();⑴ #'y#"cmQ.
//ps.addBatch();⑵ 4ecP*g
} NX}<*b/
//int [] counts = ps.executeBatch();⑶ R6(oZph
conn.commit(); 9g<7i
}catch(Exception e){ EKO[ !,
e.printStackTrace(); AB4(+S*LA
} finally{ :8OZ#D_Hl
try{ D|{jR~J)xK
if(ps!=null) { HPZ}*m'
ps.clearParameters(); Ftr5k^!
ps.close(); %\:[ o
ps=null; V;v8=1t!
} ml+; Rmvb
}catch(SQLException e){} %
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DBUtils.closeConnection(conn); a24"yT
} sfNE68I2
} !4X
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public long getLast(){ b}"N`,0dO
return lastExecuteTime; }|pwz
} P09;ng67
public void run(){ Hg=";,J
long now = System.currentTimeMillis(); ZusEfh?
if ((now - lastExecuteTime) > executeSep) { z*!%g[3I
//System.out.print("lastExecuteTime:"+lastExecuteTime); I "A_b}~*}
//System.out.print(" now:"+now+"\n"); GaK-t*Q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); e7sp =I,
lastExecuteTime=now; j-lfMEa$o
executeUpdate(); %4gg@Z9
} ;'cN<x)%|
else{ VcXq?f>\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ()6wvu}
} 32`{7a3!=
} V)[@98T_4?
} 6|PrX
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//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 yjF1}SQ
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类写好了,下面是在JSP中如下调用。 ci?qT,&
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<% %yv<y+yP~
CountBean cb=new CountBean(); ]d!
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); JPoN&BTCj
CountCache.add(cb); ~=uWD&5B4
out.print(CountCache.list.size()+"<br>"); ,Vt/(x-
CountControl c=new CountControl(); 1ng!G 7g
c.run(); x$6^R q>2
out.print(CountCache.list.size()+"<br>"); vzim<;i
%>