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: rk:^^r>5Qi
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CountBean.java hp+=UnW
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/* awh<CmcZ
* CountData.java 9HrT>{@
* ;X,|I)
* Created on 2007年1月1日, 下午4:44 {J;[
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* WzZ<ZCHm
* To change this template, choose Tools | Options and locate the template under @S\!wjl]C
* the Source Creation and Management node. Right-click the template and choose Ya{$:90(4
* Open. You can then make changes to the template in the Source Editor. H)z}6[`
*/
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package com.tot.count; TeaP\a
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/** UIgs/
* cO%-Av~P
* @author IHHL. gT
*/ low
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public class CountBean { >Lj0B%^EvM
private String countType; =i[ _C>U
int countId; =]jc{Y%o
/** Creates a new instance of CountData */ 2#LTd{
public CountBean() {} Y!s94#OaZ
public void setCountType(String countTypes){ =n.d'
this.countType=countTypes; w%F~4|F
} /ap3>xkt
public void setCountId(int countIds){ ){^o"A?-:
this.countId=countIds; KGb:NQ=O6i
} .Qk T-12
public String getCountType(){ ))m\d *
return countType; ln.'}P
} {7swE(N
public int getCountId(){ EYWRTh
return countId; y,'M3GGl
} vYb.Ub+
} D*.U?
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CountCache.java h=h4`uA9
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/* sI\v}$(~
* CountCache.java 7u7`z%
* B8A-|S!,U
* Created on 2007年1月1日, 下午5:01 T40&a(hXQ
* EQ< qN<uW
* To change this template, choose Tools | Options and locate the template under Z./$}tVUG
* the Source Creation and Management node. Right-click the template and choose %;ST7
* Open. You can then make changes to the template in the Source Editor. MYNNeO
*/ VwJ A
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package com.tot.count; sZ,xbfZby
import java.util.*; 8Ld{Xg
/** SQ&nQzL
* A$d)xq-]K
* @author &%eWCe++
*/ Wk<he F
public class CountCache { Xc8r[dX
public static LinkedList list=new LinkedList(); Lv;% z
/** Creates a new instance of CountCache */ xE>H:YPm
public CountCache() {} Y$JGpeq8w
public static void add(CountBean cb){ Q8-;w{%
if(cb!=null){ N,k PR
list.add(cb); i/UDda"E
} J:W|2U="
} )B"k;dLm
} W^dk:
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CountControl.java TOF_m$@#
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/* s'$5]9$S
* CountThread.java ` mvPbZ0<
* J>D+/[mFt
* Created on 2007年1月1日, 下午4:57 ctg U
* S7oPdzcU-
* To change this template, choose Tools | Options and locate the template under Rhw- 49AWx
* the Source Creation and Management node. Right-click the template and choose %vF,wQC
* Open. You can then make changes to the template in the Source Editor. ?XCFRt,ol
*/ \e)>]C}h
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package com.tot.count; /Z3 Mlm{
import tot.db.DBUtils; |!t&ZpdD
import java.sql.*; >qE f991SZ
/** *Wbs{>&No
* [d"]AF[#
* @author 2Xw=kw u
*/ XotiKCk|Aq
public class CountControl{ T'i^yd}*v
private static long lastExecuteTime=0;//上次更新时间 1`6kc9f.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @FNaCmBX
/** Creates a new instance of CountThread */ _PPZ!r(
public CountControl() {} da[=d*I.
public synchronized void executeUpdate(){ qStZW^lFeY
Connection conn=null; 8-#_xsZ^;
PreparedStatement ps=null; ov3FKMG?
try{ PI G3kJ
conn = DBUtils.getConnection(); "rl(%~Op
conn.setAutoCommit(false); "aL.`^.
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); x."R_>
for(int i=0;i<CountCache.list.size();i++){ DUrfC[jpv
CountBean cb=(CountBean)CountCache.list.getFirst(); ?.{SYaS
CountCache.list.removeFirst(); YL?2gBT
ps.setInt(1, cb.getCountId()); 5&
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ps.executeUpdate();⑴ 7Gh+EJJ3I
//ps.addBatch();⑵ e:9s%|]T
} !l6Ez_'
//int [] counts = ps.executeBatch();⑶ {{:QtkN
conn.commit(); Fok%
}catch(Exception e){ eW<|I
e.printStackTrace(); SAVA6
64
} finally{ ^5'pJ/BV
try{ EjA3hHJ
if(ps!=null) { uqotVil,
ps.clearParameters(); nsA}A~(E
ps.close(); ']bw37_U,
ps=null; !V^wq]D2
} 4 EE7gkM5
}catch(SQLException e){} Tv[|^G9x
DBUtils.closeConnection(conn); A4~-{.w=
} |l-~,eRvi5
} 8(zE^W,[8"
public long getLast(){ J#'8]p3E
return lastExecuteTime; }AW"2<@
} K0aT(Rc
e
public void run(){ mAM:Q*a'
long now = System.currentTimeMillis(); 9}|x
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if ((now - lastExecuteTime) > executeSep) { ikd1KF+I
//System.out.print("lastExecuteTime:"+lastExecuteTime); WqO4_;X6/
//System.out.print(" now:"+now+"\n"); jd.{J{o
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); c80Ffq
lastExecuteTime=now; oBS m>V
executeUpdate(); Hk8lHja+\
} $xU)t&Df
else{ En9>onJ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); `VrQ?s
} {Mpx33
} ~dBx<
} FoQy@GnM5
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 d=nv61]
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类写好了,下面是在JSP中如下调用。 ,+4*\yI3l
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<% Q 2>o+G
CountBean cb=new CountBean(); Nov)'2g7G
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Cu t7
CountCache.add(cb); 5O%?J-Hp
out.print(CountCache.list.size()+"<br>"); #b
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CountControl c=new CountControl(); 29HyeLB@
c.run(); F~$ay@g
out.print(CountCache.list.size()+"<br>"); -Hh.8(!XoO
%>