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: Z[__"^}
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CountBean.java o]:3H8
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/* Jc&y9]
* CountData.java lKZB?Kk^w\
* &`0/CV
* Created on 2007年1月1日, 下午4:44 \.YS%"Vz
* )WT>@
* To change this template, choose Tools | Options and locate the template under @Z>ZiU,^
* the Source Creation and Management node. Right-click the template and choose '52~$z#m
* Open. You can then make changes to the template in the Source Editor. w}Uhd,
*/ o*U]v
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package com.tot.count; Wjhvxk
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/** AdRX`[ik
* ^uv<6
* @author mKo C.J
*/ [ i#zP
public class CountBean { 4vBL6!z:Z
private String countType; ~.;<
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int countId; ;JZS^Wa
/** Creates a new instance of CountData */ -46C!6a
public CountBean() {} J+d1&Tw&
public void setCountType(String countTypes){ hW!)w
this.countType=countTypes; Z R/#V7Pj
} fd-q3_f
public void setCountId(int countIds){ cuy1DDl
this.countId=countIds; C4TE-OM8
} UfS%71l.$
public String getCountType(){ p+)Y Tzzc
return countType; 3U_2! zF3_
} V< k8N^
public int getCountId(){ C8z{XSo
return countId; o,|[GhtHqs
} [1.+HyJ}
} @v}/zS
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CountCache.java g8PTGz
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/* _h}kp\sps
* CountCache.java ^Q+g({
* /0Ax*919j
* Created on 2007年1月1日, 下午5:01 Z+@2"%W
* E Cyyl
* To change this template, choose Tools | Options and locate the template under U8
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* the Source Creation and Management node. Right-click the template and choose {%_L=2n6
* Open. You can then make changes to the template in the Source Editor. "etPT@gF
*/ M)SEn/T-
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package com.tot.count; / X1 x
import java.util.*; fW?o@vlO
/** N<~ku<nAU
* O{#=d
* @author 6?w0
*/ +SwR+H)?
public class CountCache { l+V>]?j
public static LinkedList list=new LinkedList(); ~6p[El#tS
/** Creates a new instance of CountCache */ ,G)r=$XU
public CountCache() {} T#>7ub
public static void add(CountBean cb){ o"*AtGR+"
if(cb!=null){ 812$`5l
list.add(cb); =ZqT3_
} G;YrF)\
} r?/'!!4
} -\C!I
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CountControl.java 2k=#om19
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/* <i,U )Tt^C
* CountThread.java )==Jfn y
* ?!+MM&c-n
* Created on 2007年1月1日, 下午4:57 [UH||qW
* 0\e IQp
* To change this template, choose Tools | Options and locate the template under wp&=$Aa)'
* the Source Creation and Management node. Right-click the template and choose ?"g!
* Open. You can then make changes to the template in the Source Editor. @ta7"6p-i@
*/ !jTcsN%
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package com.tot.count; 8SGo9[U2
import tot.db.DBUtils; &G-!qxe
import java.sql.*; x@[rms
/** _fKou2$yz
* xoN3
* @author i*Z"Me
*/ -PfX0y9n
public class CountControl{ #?S^kM-0
private static long lastExecuteTime=0;//上次更新时间 B8}Nvz
/
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %rv7Jy
/** Creates a new instance of CountThread */ @<elq'2
public CountControl() {} Fx2bwut.K
public synchronized void executeUpdate(){ yPal<c
Connection conn=null; B\XKw'
PreparedStatement ps=null; x U4 +|d
try{ Sn|BlXrey
conn = DBUtils.getConnection(); X<I+&Zi
conn.setAutoCommit(false); /#)/;
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 5;YMqUkw
for(int i=0;i<CountCache.list.size();i++){ Ck)*&
CountBean cb=(CountBean)CountCache.list.getFirst(); H*r)Z90
CountCache.list.removeFirst(); 4GX-ma,
ps.setInt(1, cb.getCountId()); oaIi2=Tf
ps.executeUpdate();⑴ }n>p4W"OM
//ps.addBatch();⑵ H["`Mn7j2
} :0Rx#%u}#
//int [] counts = ps.executeBatch();⑶ E4M@WNPx
conn.commit(); uo@n(>}EL
}catch(Exception e){ '2 PF
e.printStackTrace(); GJ_7h_4
} finally{ QD0"rxZJ
try{ )% ~OH
if(ps!=null) { N(Fp0
ps.clearParameters(); Tu).K.p:
ps.close(); AHX St
ps=null; oY933i@l)P
} v]B3m
}catch(SQLException e){} G?Q3/y(
DBUtils.closeConnection(conn); N/MUwx;P
} |Uc_G13Y{D
} 4b98KsYg
public long getLast(){ sT}.v*
return lastExecuteTime; rustMs2p
} Z$/xy"
public void run(){ ^c9t'V`IWQ
long now = System.currentTimeMillis(); CEX"D`
if ((now - lastExecuteTime) > executeSep) { +JjW_Rl?=V
//System.out.print("lastExecuteTime:"+lastExecuteTime); n[lJLm^(_C
//System.out.print(" now:"+now+"\n"); ^\4h<M
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {y=j?lD
lastExecuteTime=now; iO|se:LY<
executeUpdate(); iOW#>66d
} Ab{ K<:l
else{ 9_Be0xgJ3^
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2AT5
} H|3:6x
} RBs-_o+ %
} 2N: ,Q8~
//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 A#EDkU,
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类写好了,下面是在JSP中如下调用。 "@iK'
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<% Vl&?U
CountBean cb=new CountBean(); &,{fw@#)_
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ]>=}*=
CountCache.add(cb); I ?gSG*m
out.print(CountCache.list.size()+"<br>"); Ya3C#=
CountControl c=new CountControl(); =8AO:
c.run(); ;f#v0W`5
out.print(CountCache.list.size()+"<br>"); $u]jy0X<Y;
%>