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: Nd]0ta
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CountBean.java ;jRL3gAe)
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/* { c v;w
* CountData.java 6V'wQqJ
* /M0l
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* Created on 2007年1月1日, 下午4:44 3[MdUj1y[
* :`:xP
* To change this template, choose Tools | Options and locate the template under =3h+=l[
* the Source Creation and Management node. Right-click the template and choose ,bB( 24LD
* Open. You can then make changes to the template in the Source Editor. "-G&=(
*/ u/z,92mmS
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package com.tot.count; W0VA'W
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/** >}ro[x`K
* <T(s\N5B=
* @author =}~NRmmF
*/ I["F+kt^^
public class CountBean { [:AB$l*
private String countType; 5Z*
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int countId; T&o,I
/** Creates a new instance of CountData */ m(2G*}
public CountBean() {} j`>?"1e@x
public void setCountType(String countTypes){ lr9=OlH
this.countType=countTypes; ?wGiog<Q{
} JaH*
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public void setCountId(int countIds){ ?"()>PJx
this.countId=countIds; oUl=l}qnD
} X}3P1.n:
public String getCountType(){ ]WTf< W<
return countType; ]O6KKz
} ^H'hD
public int getCountId(){ M%7`8KQ
return countId; @''&nRC1
} w@87]/ 4Rq
} i?ZA x4D
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CountCache.java J$1j-\KS
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/* [?;`x&y~y
* CountCache.java gsnP!2cR
* =hJfL}&O3
* Created on 2007年1月1日, 下午5:01 A;odVaH7
* S$S_nNq
* To change this template, choose Tools | Options and locate the template under C>AcK#-x,{
* the Source Creation and Management node. Right-click the template and choose Z+Kv+GmqH
* Open. You can then make changes to the template in the Source Editor. K|`+C1!
*/ J2rvJ2l=t
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package com.tot.count; [m~b[ZwES
import java.util.*; uZ@-e|qto
/** ksTzXG8
* {d| |q<.-
* @author 7raSf&{&6b
*/ E|Q{]&$;Z"
public class CountCache { S
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public static LinkedList list=new LinkedList(); /rqqC(1
/** Creates a new instance of CountCache */ qpoquWZ
public CountCache() {} - o4@#p> >
public static void add(CountBean cb){ I|H,)!Z
if(cb!=null){ 7 n\mj\
list.add(cb); ):/,w!1
}
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} OWqrD@
} -UJ?L
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CountControl.java aD+0\I[x
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/* ~D*b3K8X
* CountThread.java /j11,O?72
* I"B8_
* Created on 2007年1月1日, 下午4:57 g8KY`MBnC&
* ,g%o
* To change this template, choose Tools | Options and locate the template under *nLIXnm
* the Source Creation and Management node. Right-click the template and choose <} &7 a s
* Open. You can then make changes to the template in the Source Editor. R|-6o)$
*/ Sc$gnUYD{
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package com.tot.count; 9t#P~>:jY}
import tot.db.DBUtils; FQ U\0<5
import java.sql.*; g`kY]lu
/** i[PvDv"n
* mU50pM~/i
* @author 5bXHz5i
*/ r)Or\HL
public class CountControl{ `Uv)Sf{
private static long lastExecuteTime=0;//上次更新时间 DTPay1]6
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 )Ea8{m!
/** Creates a new instance of CountThread */ Hc M~
public CountControl() {}
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public synchronized void executeUpdate(){ +)zDA:2Wa"
Connection conn=null; Yhe+u\vGs\
PreparedStatement ps=null; "2%>M
try{ sA3UeTf
conn = DBUtils.getConnection(); k'g$2
conn.setAutoCommit(false); %06vgjOa (
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); c&
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for(int i=0;i<CountCache.list.size();i++){ F%Kp9I*
CountBean cb=(CountBean)CountCache.list.getFirst();
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CountCache.list.removeFirst(); h!v/s=8c
ps.setInt(1, cb.getCountId()); '5AvT:
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ps.executeUpdate();⑴ n3'dLJH|
//ps.addBatch();⑵ WK*S4c
} MO-!TZ+6
//int [] counts = ps.executeBatch();⑶ _AprkI_
conn.commit(); kymn)Ea
}catch(Exception e){
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e.printStackTrace(); xHHV=M2l(s
} finally{ V`[P4k+b
try{ `os8;`G
if(ps!=null) { (|dPeix|
ps.clearParameters(); <~N%W#z/
ps.close(); Vg{Zv4+t
ps=null; _PV*lK=
} mW~P!7]
}catch(SQLException e){} U_l7CCK +
DBUtils.closeConnection(conn); pr$~8e=c
} D;jK/2
} :&9TW]*g
public long getLast(){ Ge^Qar
return lastExecuteTime; ~H u"yAR
} 1+a@k
public void run(){ &Xv1[nByU
long now = System.currentTimeMillis(); 7-X/>v
if ((now - lastExecuteTime) > executeSep) { {\EOo-&A
//System.out.print("lastExecuteTime:"+lastExecuteTime);
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//System.out.print(" now:"+now+"\n"); MQJ%He"
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 3 "Yif
lastExecuteTime=now; 9KyZEH;pY
executeUpdate(); BRa{\R^I
} d/]|657u
else{ k1#5nYN.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -6`;},Yr
} a8zZgIV
} mB`D}g$
} lufeieW
//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 L<=) @7
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类写好了,下面是在JSP中如下调用。 vOe0}cR
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<% 84^[/d;!
CountBean cb=new CountBean(); E M Q4yK
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ZE
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CountCache.add(cb); C U$)QH{
out.print(CountCache.list.size()+"<br>");
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CountControl c=new CountControl(); +I@cO&CY|
c.run(); {p]=++
out.print(CountCache.list.size()+"<br>"); &\^rQi/tf
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