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: |k90aQO
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CountBean.java >@Ht*h{~
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/* ?.%dQ0
* CountData.java r>FwJm!
* |,:p[Oy
* Created on 2007年1月1日, 下午4:44 ]S[/a
* .4[3r[
* To change this template, choose Tools | Options and locate the template under T\bP8D
* the Source Creation and Management node. Right-click the template and choose ]q{_i
* Open. You can then make changes to the template in the Source Editor. m<-!~ ew
*/ 4jC)"tch
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package com.tot.count; I2}eFz&FE
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/** +"<+JRI(M5
* Vez8~r3
* @author N;'c4=M~(
*/ jK]1X8
public class CountBean { 2{63:f1c`'
private String countType; cI\[)5&
int countId; z5]6"v-
/** Creates a new instance of CountData */ 8I/3T
public CountBean() {} X:g5;NT
public void setCountType(String countTypes){ GIxs>E'X
this.countType=countTypes; 0LH6G[
} Dk^AnMx%_
public void setCountId(int countIds){ 0Q&(j7`^@
this.countId=countIds; e~zgH\`
} `HQ)][
public String getCountType(){ 4BCe;Q^6
return countType; ^g vTc+|
} X\P%C
public int getCountId(){ -i2rcH
return countId; rx2'].
} |_TI/i>?'
} |*NZ^6`@
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CountCache.java [M~tH *4"
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/* 77O$^fG2
* CountCache.java [m0X kvd
* /"?DOsJ.
* Created on 2007年1月1日, 下午5:01 W<prY
* yj&GJuNb~
* To change this template, choose Tools | Options and locate the template under cZ:jht
* the Source Creation and Management node. Right-click the template and choose (b f
IS
* Open. You can then make changes to the template in the Source Editor. +:;ddV
*/ bp:`m>4<
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package com.tot.count; y'!OA+ob
import java.util.*; H)D|lt5xy
/** A|r3c?q
* K9k!P8Rd
* @author Q*>)W{H&)
*/ x5Lbe5/P
public class CountCache { 37zBX~
public static LinkedList list=new LinkedList(); :,JaOn'
/** Creates a new instance of CountCache */ 3Xu|hkK\e
public CountCache() {} 5N|LT8P}Z
public static void add(CountBean cb){ C(G.yd
if(cb!=null){ hXjZ>n``
list.add(cb); xjo`u:BH
} Deh3Dtg/k
} <3B^5p\/
} kPs?
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CountControl.java /#Aw7F$Ey
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/* /\/^= j
* CountThread.java |?^<=%
* NLMvi!5w,
* Created on 2007年1月1日, 下午4:57 ,w#lUgp
* R}0gIp=
* To change this template, choose Tools | Options and locate the template under R|\eBnfI
* the Source Creation and Management node. Right-click the template and choose ?CQE6ch
* Open. You can then make changes to the template in the Source Editor. _f%s]
*/ /@ @F
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package com.tot.count; v zg^tJ
import tot.db.DBUtils; Hloe7+5UD
import java.sql.*; ^}-l["u`
/** DPzW,aIgv
* )sm9%|.&
* @author ISpV={$Zd
*/ y5j:+2|I
public class CountControl{ hUlRtt
private static long lastExecuteTime=0;//上次更新时间 Zt3sU_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 a|u#w~
/** Creates a new instance of CountThread */ M?h{'$T
public CountControl() {} G7 UUx+ X
public synchronized void executeUpdate(){ ['}|#3*w
Connection conn=null; $?PI>9g!
PreparedStatement ps=null; ?l9sj]^w
try{ XZ
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conn = DBUtils.getConnection(); ]AY 4bm
conn.setAutoCommit(false); Ww-x+U\l
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ..8t1+S6]
for(int i=0;i<CountCache.list.size();i++){ k2D*`\
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CountBean cb=(CountBean)CountCache.list.getFirst(); tw$EwNI[
CountCache.list.removeFirst(); J=3{<Xl
ps.setInt(1, cb.getCountId()); 4P3RRS
ps.executeUpdate();⑴ _s^tL2Pc
//ps.addBatch();⑵ h.vy SwF"j
} uy<3B>3~.
//int [] counts = ps.executeBatch();⑶ vMp=\U-~^
conn.commit(); ;-u]@35
}catch(Exception e){ Mgw#4LU
e.printStackTrace(); 89&9VX^A
} finally{ C|&tdh :g
try{ 2X2Ax~d@
if(ps!=null) { ;O hQBAC
ps.clearParameters(); 8?nn4]P
ps.close();
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ps=null; M
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} uQ W)pD{_
}catch(SQLException e){} .:j{d}p}
DBUtils.closeConnection(conn); q0+N#$g#
} Bo"9;F
} 3%)cUkD
public long getLast(){ `VwG]2 I
return lastExecuteTime; LLTr+@lj
} QPf\lN/$4d
public void run(){ B9"o Ru^}
long now = System.currentTimeMillis(); HKJCiQ|k
if ((now - lastExecuteTime) > executeSep) { ;I*t5{
//System.out.print("lastExecuteTime:"+lastExecuteTime); kc2B_+Y1
//System.out.print(" now:"+now+"\n"); 0cHcBxdF
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Eg`~mE+a
lastExecuteTime=now; M$EF 8
executeUpdate(); UmVn: a
} ,9ueHE
else{ "QOQ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); g4WmUV#wp
} vb~%u;zrC@
} ;&j'`tP
} >k"O3Pc@
//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 SdlO]y9E
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类写好了,下面是在JSP中如下调用。 QwhO/
|^ 8ND#x
<% 55O}S Us!P
CountBean cb=new CountBean(); VjWJx^ZL#
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Hi[lN7ma8
CountCache.add(cb); q<E7qY+
out.print(CountCache.list.size()+"<br>"); c/K#W$ l
CountControl c=new CountControl(); HHx:s2G
c.run(); 6h/!,j0:t_
out.print(CountCache.list.size()+"<br>"); ^ZsIQ4 @`
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