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: XJeWhk3R9
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CountBean.java }WIkNG4{Z
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/* we`BqZV
* CountData.java SXqB<j$.;
* /i>n1>~yn
* Created on 2007年1月1日, 下午4:44 Rkg8
* NJsaTBT
* To change this template, choose Tools | Options and locate the template under U&BCd$
* the Source Creation and Management node. Right-click the template and choose KLW5Ad:/rI
* Open. You can then make changes to the template in the Source Editor. T(x@gwc
*/ L5x;#\#p
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package com.tot.count; E8r6P:5d`
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/** "NA<^2W@J
* XyN
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* @author $+GDPYm'
*/ }wiyEVAh{
public class CountBean { *w4#D:g
private String countType; S:j{R^$k
int countId; %P s.r{%{
/** Creates a new instance of CountData */ Vq]ixag2^
public CountBean() {} i;9X_?QF
public void setCountType(String countTypes){ 2_HIn
this.countType=countTypes; xA7~"q&u
} >eG<N@13p
public void setCountId(int countIds){ 63l&
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this.countId=countIds; f4P({V
} ^zV_vB)n
public String getCountType(){ C\5G43`
return countType; QyVAs ;
} )S+fc=
public int getCountId(){ vx($o9
return countId; XjL3Ar*
} yYJ_;Va
} _"@:+f,
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CountCache.java [G$ #jUt/O
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/* \O "`o4
* CountCache.java hH5~T5?\
* f}2}Ta
* Created on 2007年1月1日, 下午5:01 Z
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* \_,p@r]Q
* To change this template, choose Tools | Options and locate the template under TSewq4`K
* the Source Creation and Management node. Right-click the template and choose vc"!3x-G*
* Open. You can then make changes to the template in the Source Editor. I9G^T' W
*/ ``jNj1t{}
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package com.tot.count; s$pXn&:
import java.util.*; 1-E6ACq
/** 2k<#e2
* /lUfxc4
* @author 7s6+I_n
*/ cX
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public class CountCache { GgY8\>u
public static LinkedList list=new LinkedList(); [pTdeg;QE
/** Creates a new instance of CountCache */ -W^{)%4g
public CountCache() {} $]_SPu
public static void add(CountBean cb){ {Cm!5Q Yy
if(cb!=null){ ,L-/7}"VHA
list.add(cb); <!RkkU&
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} 34!.5^T
} YRVh[Bqg`
} qI7KWUR
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CountControl.java Vxap+<m
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/* +7w5m
* CountThread.java rZdOU?U
* Lp:VU-S
* Created on 2007年1月1日, 下午4:57 xS_;p9{E
* ' F.^ 8/>
* To change this template, choose Tools | Options and locate the template under lfDd%.:q4S
* the Source Creation and Management node. Right-click the template and choose _1E c54D
* Open. You can then make changes to the template in the Source Editor. 13F]7l-#
*/ @Nsn0-B?ne
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package com.tot.count; ^
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import tot.db.DBUtils; *:TwO=)
import java.sql.*; `ZEFH7P
/** ;]1t|td8
* c6vJ;iz
* @author }nPt[77U_7
*/ ]'Eg2(wy
public class CountControl{ zGU MH7 M
private static long lastExecuteTime=0;//上次更新时间 ?:9y
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Vv+nq_
/** Creates a new instance of CountThread */ 7<]&pSt=
public CountControl() {} %OgK{h
public synchronized void executeUpdate(){ i
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Connection conn=null; K_L7a>Fr
PreparedStatement ps=null; &j:prc[W
try{ 'e]>lRZ
conn = DBUtils.getConnection(); 8[J%TWq%9
conn.setAutoCommit(false); 3@x[M?$
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); L @T/4e./
for(int i=0;i<CountCache.list.size();i++){ Kt*b)
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CountBean cb=(CountBean)CountCache.list.getFirst(); :'wxm3f
CountCache.list.removeFirst(); A)9]^@,
ps.setInt(1, cb.getCountId()); ]pe7I
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ps.executeUpdate();⑴ eGQ4aQhi
//ps.addBatch();⑵ (LTu=1
} m-uXQS^@G
//int [] counts = ps.executeBatch();⑶ Vc9Bg2f5
conn.commit(); 1(Vv-bq$
}catch(Exception e){ I= :yfW
e.printStackTrace(); D+uo gRS61
} finally{ v[uVAbfQ
try{ j;}-x1R
if(ps!=null) { s:6K'*
ps.clearParameters(); d)uuA;n
ps.close(); ZVH 9je
ps=null; wwdmz;0S
} Xk|a%%O*H
}catch(SQLException e){} i/_rz.c~3
DBUtils.closeConnection(conn); Wtu-g**KN
} yWRIh*>nE
} %52e^,//
public long getLast(){ Pq+|*Y<|&
return lastExecuteTime; X~VI} dJ
} HqV55o5f'
public void run(){ PH%t#a!j3/
long now = System.currentTimeMillis(); vT{(7m!Ra
if ((now - lastExecuteTime) > executeSep) { kXhd]7ru
//System.out.print("lastExecuteTime:"+lastExecuteTime); `TO Xktj
//System.out.print(" now:"+now+"\n"); 'Y2$9qy-L
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); XHJdynt/
lastExecuteTime=now; KtAEM;g
executeUpdate(); [\Wl~
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} I_f%%N%
else{ E!}'cxb^
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); g0biw?
} o0No"8DnjH
} YC%xW*
} dl=)\mSFjF
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 &J/!D#
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类写好了,下面是在JSP中如下调用。 .&b^6$dC
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<% /Hk})o_
CountBean cb=new CountBean(); 66>X$nx(z
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); -]KgLgJ
CountCache.add(cb); 7<70\6
out.print(CountCache.list.size()+"<br>"); Vr1r2G2
CountControl c=new CountControl(); 0c"9C_7^g
c.run(); 2UYtEJ(?`{
out.print(CountCache.list.size()+"<br>"); h/C{
%>