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: 9 D7+[`r(-
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CountBean.java _i20|v
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/* go'-5in(
* CountData.java Mdl{}P0)
* maXG:l|
* Created on 2007年1月1日, 下午4:44 4iKgg[)7`=
* @JyK|.b#0
* To change this template, choose Tools | Options and locate the template under Q$="_y2cTA
* the Source Creation and Management node. Right-click the template and choose c.>oe*+
* Open. You can then make changes to the template in the Source Editor. %?p1d!
*/ {\c(ls{
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package com.tot.count; $shoasSuI
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/** d`
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* qzf!l"bT
* @author 2T V X)q<\
*/ m^GJuPLW
public class CountBean { IW@PF7
private String countType; 2vAQ
int countId; |MFF7z{%
/** Creates a new instance of CountData */ a2
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public CountBean() {} o]; [R
public void setCountType(String countTypes){ ( 5tvfz%
this.countType=countTypes; G0^2Wk[
} 6~1|qEe6I
public void setCountId(int countIds){ ~TSy<t~%-
this.countId=countIds; gx\&_)w N
} >hk=VyU;
public String getCountType(){ )u/yF*:n
return countType; 6^%68N1k
} rL+!tH
public int getCountId(){ 1n:8s'\
return countId; ?<(m
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} &8l%T'gd
} d5D$&5Ec
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CountCache.java 3b+d"`Y^S
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/* V`bi&1?6\
* CountCache.java 5A
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* ,!7 H]4Qx
* Created on 2007年1月1日, 下午5:01 1e&QSzL
* $`z)~6'
* To change this template, choose Tools | Options and locate the template under (UU(:/
* the Source Creation and Management node. Right-click the template and choose iy 14mh\ ~
* Open. You can then make changes to the template in the Source Editor. ?i06f,-
*/ `eIenA
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package com.tot.count; W!6qqi{
import java.util.*; 11<KpxKpk
/** Bh=u|8yxc
* }T%}wdj
* @author 4*e0 hWp
*/ ~ ; -! n;
public class CountCache { N1|$$9G+
public static LinkedList list=new LinkedList(); ZE2$I^DY-
/** Creates a new instance of CountCache */ ~[\_N\rm
public CountCache() {} jC7&s$>Q"g
public static void add(CountBean cb){ IFDZfx
if(cb!=null){
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list.add(cb); }lfnnK#
} dVsE^jsL
} $D}{]MN.
} Mi/&f
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CountControl.java 2UFv9
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/* (Nx;0"5IX
* CountThread.java h\PHKC2
* Ee3hG2d`
* Created on 2007年1月1日, 下午4:57 op6CA "w
* 1. rj'
* To change this template, choose Tools | Options and locate the template under L(khAmm
* the Source Creation and Management node. Right-click the template and choose l PK
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* Open. You can then make changes to the template in the Source Editor. ,=|ZB4HA
*/ + j W1V}h
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package com.tot.count; 1;mW,l'`
import tot.db.DBUtils; U5He?
import java.sql.*; Q)LM-ZJKQ
/** hED=u/ql[
* <j5NFJ9
* @author Oh'Y0_oB>
*/ %7gkNa
public class CountControl{ R0L&*Bjm
private static long lastExecuteTime=0;//上次更新时间 av$/Om:
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 h3Q21D'f
/** Creates a new instance of CountThread */ _h":>
public CountControl() {} 9Iz%ht
public synchronized void executeUpdate(){ hb^7oq"a
Connection conn=null; "V$Bnz\n
PreparedStatement ps=null; w*|7!iM
try{ {WPobP"
conn = DBUtils.getConnection(); Qbyv{/
conn.setAutoCommit(false); qfK`MhA}
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); &d5ia+#
for(int i=0;i<CountCache.list.size();i++){ tWoh''@#
CountBean cb=(CountBean)CountCache.list.getFirst(); GF5^\Rf
CountCache.list.removeFirst(); E5N{j4\F
ps.setInt(1, cb.getCountId()); ea~:}!-P
ps.executeUpdate();⑴ OBP1B@|l$+
//ps.addBatch();⑵ 2c:#O%d(
} =<NljOR4`
//int [] counts = ps.executeBatch();⑶ *H.oP
conn.commit(); yZ7,QsEsN
}catch(Exception e){ Hf vTxaK
e.printStackTrace(); Ie4 hhW
} finally{ HjGyj/78w
try{ ]f_6 '|5A
if(ps!=null) { 9>g,
ps.clearParameters(); W"k8KODOY
ps.close(); Ce")[<:
ps=null; 6'RrQc=q
} gF5a5T,
}catch(SQLException e){} Tp9-niW
DBUtils.closeConnection(conn); |)K]U
} h?FmBK'BAd
} L[20m(6?
public long getLast(){ qq1 - DG
return lastExecuteTime; mBG=jI "xh
} BYo/57&:
public void run(){ nYa*b=[.
long now = System.currentTimeMillis(); 6^c>,.R
if ((now - lastExecuteTime) > executeSep) { ^+m+zd_
//System.out.print("lastExecuteTime:"+lastExecuteTime); i6 (a@KRY
//System.out.print(" now:"+now+"\n"); ZU9c 5/J
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); OKvPL=~
lastExecuteTime=now; S:x?6IDPC^
executeUpdate(); f}@jFhr'<
} (<Th=Fns?
else{ =pk)3<GwF
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <@Fy5k-%.
} N]<!j$pOz
} L
} ~2zMkVH
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 0sh/|`\
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类写好了,下面是在JSP中如下调用。 Xj5~%DZp
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<% yGsz2T;w
CountBean cb=new CountBean(); B-T/V-c7
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _"#!e{N|
CountCache.add(cb); n]u<!.X
out.print(CountCache.list.size()+"<br>"); yH<$k^0r*
CountControl c=new CountControl(); E gDQ+(
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c.run(); H=\!2XS
out.print(CountCache.list.size()+"<br>"); )5.C]4jol
%>