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: )pJ}
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CountBean.java 3vfm$sx@
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/* >k"Z'9l
* CountData.java U$&G_&*0a
* @@"}i7
* Created on 2007年1月1日, 下午4:44 'c*Q/C;
* OS;qb:;
* To change this template, choose Tools | Options and locate the template under _HW~sz|
* the Source Creation and Management node. Right-click the template and choose !}<d6&!py
* Open. You can then make changes to the template in the Source Editor. S}f3b N
*/ T!0o(Pp<
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package com.tot.count; 'G;y!<a
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/** l=ehoyER
* ~[l6;bn
* @author u9ObFm$7
*/ 0}C> e`<'
public class CountBean { }:<`L\8q\
private String countType; 4$#nciAe
int countId; m-Q!V+XQp
/** Creates a new instance of CountData */ ``$Dgj[
public CountBean() {} {VtmQU?cJ
public void setCountType(String countTypes){ cVYDO*N2T
this.countType=countTypes; S
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} dmI~$*
public void setCountId(int countIds){
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this.countId=countIds;
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} v W=$C
public String getCountType(){ HX%lL}E
return countType; iZ}Afj
} n}/?nP\%
public int getCountId(){ }'L7< _
return countId; E}LuWFZ&
} ;rXkU9
} }K':tX?
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CountCache.java +z}O*,M"q
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/* (8T36pt~
* CountCache.java sQUJ]h
* 3D32'KO_"
* Created on 2007年1月1日, 下午5:01 7iMBDkb7
* nX~Qt%
* To change this template, choose Tools | Options and locate the template under b* k=
* the Source Creation and Management node. Right-click the template and choose _/(DEF+G
* Open. You can then make changes to the template in the Source Editor. TgMa!Vz
*/ cCx@VT`0
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package com.tot.count; p}H:t24Cr5
import java.util.*; $WmB __
/** t|-TG\Q X
* 9<0TF+}>
* @author e.-+zkQ8EI
*/ cjK\(b3
public class CountCache { O&BNhuW2
public static LinkedList list=new LinkedList(); )45~YDS;t
/** Creates a new instance of CountCache */ cHo@F!{o=
public CountCache() {} NZT2ni4
public static void add(CountBean cb){ p[oR4 HWr
if(cb!=null){ %87D(h!.I4
list.add(cb); 1g_p`(
} "/H B#
} 7Z%EXDm4/c
} pRR1k?
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CountControl.java (bhMo^3/*
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/* [0c7fH`8V
* CountThread.java wHx@&Tp
* JTGA\K
* Created on 2007年1月1日, 下午4:57 D)shWJRlvW
* wavyREK
* To change this template, choose Tools | Options and locate the template under a(.q=W
* the Source Creation and Management node. Right-click the template and choose 6sceymq
* Open. You can then make changes to the template in the Source Editor. p+x}$&<|
*/ ?e=3G4N
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package com.tot.count; f2h`bO
import tot.db.DBUtils; +vf~s^
import java.sql.*; ;OC~,?O5
/** 7`xeuK
* )<ig6b%
* @author CgT5sk}
*/ _*iy *:(o
public class CountControl{ <S[]VXy
private static long lastExecuteTime=0;//上次更新时间 i ZU1w7Z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 unX mMSz(
/** Creates a new instance of CountThread */ ZG(. Q:1
public CountControl() {} S<*h1}V3/
public synchronized void executeUpdate(){ m8}c(GwcP
Connection conn=null; J|$UAOEDa
PreparedStatement ps=null; ,c]<Yu
try{ IKo,P$
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conn = DBUtils.getConnection(); r0^ *|+
conn.setAutoCommit(false); ,zF^^,lO7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ?uAq goCl
for(int i=0;i<CountCache.list.size();i++){ A4K8DP
CountBean cb=(CountBean)CountCache.list.getFirst(); K92nh/}y
CountCache.list.removeFirst(); wWYo\WH'
ps.setInt(1, cb.getCountId()); itYTV?bd
ps.executeUpdate();⑴
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//ps.addBatch();⑵ *ggai?
} . E8Gj'yO
//int [] counts = ps.executeBatch();⑶ xg(*j[ff3
conn.commit(); op8[8pt%
}catch(Exception e){ Mi^/`1
e.printStackTrace(); yC&u^{~BC
} finally{ +HDfEo T
try{ =Ju%3ptH0
if(ps!=null) { q%S^3C&
ps.clearParameters(); _a]0<Vm C0
ps.close(); evSr?ys
ps=null; } "QL"%
} ,vDSY N6
}catch(SQLException e){} z( !K8
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DBUtils.closeConnection(conn); O'rz
} }1kZF{KD<[
} } *:H\GL
public long getLast(){ tUGnp'r
return lastExecuteTime; <nvzNXql
} \+Nn>wW.
public void run(){ -3GlpC22
long now = System.currentTimeMillis(); `;
+UWdAR
if ((now - lastExecuteTime) > executeSep) { MSqW {
//System.out.print("lastExecuteTime:"+lastExecuteTime); U{,:-R
//System.out.print(" now:"+now+"\n"); b?U2g?lN:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [iXk v\
lastExecuteTime=now; <`)vp0
executeUpdate(); 2#81oz&K
} r }S>t~p:
else{ Zdfruzl&`
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]Uj7f4)k
} b3 NEYn
} .;J6)h
} vu@@!cT6e
//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 oUd R,;h9
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类写好了,下面是在JSP中如下调用。 jR[b7s
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<% a7U`/*
CountBean cb=new CountBean(); (jI _Dk;
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {Gvv^.H7
CountCache.add(cb); GMKY1{
out.print(CountCache.list.size()+"<br>"); dbG902dR
CountControl c=new CountControl(); RW`+F|UbE
c.run(); \=2<<
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out.print(CountCache.list.size()+"<br>"); IY,n7x0d
%>