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: VX]Ud\(
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CountBean.java v9XevLs
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/* E?cf#;2h8m
* CountData.java ]3I@5 }5%
* m)e~HP7M
* Created on 2007年1月1日, 下午4:44 uh&Qdy!I
* cNiNLwc
* To change this template, choose Tools | Options and locate the template under gX;)A|9e
* the Source Creation and Management node. Right-click the template and choose 8&c:73=?X
* Open. You can then make changes to the template in the Source Editor. buA/G-<e
*/ IyoitIbLl
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package com.tot.count; ]oizBa@?G
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/** Q+; N(\
* \VHRI<$+5
* @author %z"n}|%!
*/ z4wG]]Kh*
public class CountBean { iE,/x^&,&
private String countType; A1F!I4p5
int countId; %&pd`A/
/** Creates a new instance of CountData */ $<F9;Z
public CountBean() {} I
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public void setCountType(String countTypes){ m\@ q2l-
this.countType=countTypes; .RN2os{
} L&G5 kY`
public void setCountId(int countIds){ &{ZTtK&JF
this.countId=countIds; sjG@4Or
} L^e%oQ>s
public String getCountType(){ k@^T<Ci
return countType; Oz-@e%8L
} j71RlS73
public int getCountId(){ gIY]hC.
return countId; 8DcIM(;Z
} i9v|*ZM"
} |G(I,EPag
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CountCache.java As>P(
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/* } T&~DVM
* CountCache.java z@U5
* UNyk,
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* Created on 2007年1月1日, 下午5:01 (\H^KEy
* M+-1/vR *@
* To change this template, choose Tools | Options and locate the template under A?"/ >LM
* the Source Creation and Management node. Right-click the template and choose m4,inA:o
* Open. You can then make changes to the template in the Source Editor. l\HtP7]
*/ +%?\#E QJ
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package com.tot.count; \
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import java.util.*; e,Sxu[2
/** l^R1XBP
* 8XD_p);Oy
* @author |6 E
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*/ N7-LgP
public class CountCache { S#N4!"
public static LinkedList list=new LinkedList(); PZk"!I<oN
/** Creates a new instance of CountCache */ epG!V#I
public CountCache() {} lN'b"N
public static void add(CountBean cb){ \T {<{<n
if(cb!=null){ ca,U>'(y
list.add(cb); S3gd'Bahq
} a\tv,Lx
} WP >VQZ&
} t(Gg
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CountControl.java $Go)Zs-bL?
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/* XvI Y=~
* CountThread.java Zb$P`~(%
* `!y/$7p
* Created on 2007年1月1日, 下午4:57 4q*mEV
* 5U6b\jxX
* To change this template, choose Tools | Options and locate the template under {QVs[
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* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. .svlJSx
*/ EM!9_8 f
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package com.tot.count; 2<tU
import tot.db.DBUtils; cBQ+`DXn5c
import java.sql.*; !YIW8SP)
/** H0-v^H>^
* $fG~;`T
* @author 4nKlW_{,
*/ I8VCR8q
public class CountControl{ )wCV]TdF
private static long lastExecuteTime=0;//上次更新时间 [ps5
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 PG@6*E
/** Creates a new instance of CountThread */ o ^""=Z
public CountControl() {} 30{WGc@l#
public synchronized void executeUpdate(){ ~2[mZias
Connection conn=null; -`,Fe3
PreparedStatement ps=null; ahg]OWn#
try{ xM**n3SZ`
conn = DBUtils.getConnection(); gmN$}Gy}
conn.setAutoCommit(false);
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +^ `n- m
for(int i=0;i<CountCache.list.size();i++){ JzmX~|=Xi
CountBean cb=(CountBean)CountCache.list.getFirst(); ;&$f~P Q
CountCache.list.removeFirst(); 9}z%+t8u
ps.setInt(1, cb.getCountId()); B:#9
ps.executeUpdate();⑴ IC+!XZqS
//ps.addBatch();⑵ 3ICM H
} bVOJp% *s
//int [] counts = ps.executeBatch();⑶ 23/;W|
conn.commit(); 75eZhs[b
}catch(Exception e){ R7/ET"
e.printStackTrace(); 6/.cS4
} finally{ remRmY?
try{ T+41,
if(ps!=null) { 2k!4oVUN
ps.clearParameters(); Sh\Jm*5
ps.close(); C sCH :>
ps=null; mb*|$ysPx
} uMX\Y;N
}catch(SQLException e){} 7'Gkip
DBUtils.closeConnection(conn); Y{9xF8#
} w#{S=^`}
} iC~ll!FA!
public long getLast(){ }ZJJqJ`*e
return lastExecuteTime; cFr`9A\-n
} _kdt0Vr,L
public void run(){ czT]XF
long now = System.currentTimeMillis(); ]nq/yAF%
if ((now - lastExecuteTime) > executeSep) { :ka^ztXG
//System.out.print("lastExecuteTime:"+lastExecuteTime); 3<_=Vyf
//System.out.print(" now:"+now+"\n"); ^u> fW["[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); qK]Om6 a~
lastExecuteTime=now; AA0\C_W0p
executeUpdate(); z@v2t>@3k
} X<&Y5\%F
else{ 3,1HD_
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1 Q*AQYVY
} JC
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} Rw)=<XV)6
} ( e4#9
//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 Y|E rVf4
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类写好了,下面是在JSP中如下调用。 #'BPW<Ob
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<% }J $\<ZT
CountBean cb=new CountBean(); BT"n;L?[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ]Rj?OSok
CountCache.add(cb); \k5
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out.print(CountCache.list.size()+"<br>"); h}Lrp r2r
CountControl c=new CountControl(); #U.6HBuQa
c.run(); S=G2%u!;
out.print(CountCache.list.size()+"<br>"); 1v 4M*
%>