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: ><DE1tG
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CountBean.java %q!nTGU~
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/* A6Qi^TI
* CountData.java 4@Qq5kpk*
* l-npz)EM
* Created on 2007年1月1日, 下午4:44 }Ag2c; aaq
* lwB!ti
* To change this template, choose Tools | Options and locate the template under 2]'ozs$|v
* the Source Creation and Management node. Right-click the template and choose w])Sz*J
* Open. You can then make changes to the template in the Source Editor. &S{F"z
*/ oc?VAF
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package com.tot.count; D;E&;vP6%
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/** = G_6D
* j?,$*Fi
* @author {%$=^XO
*/ mU_O64
public class CountBean { 8L@di Y
private String countType; 04"hQt{[
int countId; GQQ!3LwP\O
/** Creates a new instance of CountData */ ])JJ`Z8Bk
public CountBean() {} 5-J-Tn
public void setCountType(String countTypes){ ~+g5?y
this.countType=countTypes; 5SjS~9
} ?\yo~=N^
public void setCountId(int countIds){ KXGs'D
this.countId=countIds; nk{1z\D{
} I@B7uFj
public String getCountType(){ bM'AD[
return countType; p)ONw"sb
} ~DD/\V
public int getCountId(){ ,yF)7fN
return countId; nGt8u4gcP
} w*}9;l
} g,;MV7yE
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CountCache.java B?M+`;
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/* 6IX!9I\sT
* CountCache.java 8+u8piG
* gM*s/,;O"
* Created on 2007年1月1日, 下午5:01 Vh<`MS0X
* Dz{e@+>M
* To change this template, choose Tools | Options and locate the template under a !IH-XJ2
* the Source Creation and Management node. Right-click the template and choose ZUu^==a
* Open. You can then make changes to the template in the Source Editor. W< n`[
*/ 9NT;^K^I
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package com.tot.count; 0b4OJ[
import java.util.*; t'J
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/** }:%pOL n
* q2Kn3{
* @author jz)H?UuDY
*/ piP8ObGjy
public class CountCache { H07j&
public static LinkedList list=new LinkedList(); |}`5<a!6U
/** Creates a new instance of CountCache */ (TE2t7ab|M
public CountCache() {} =T-w.}27O
public static void add(CountBean cb){ 1bBK1Uw
if(cb!=null){ JvDsr0]\#
list.add(cb); WdT|xf.Q&
} HZ}*o%O
} gY9"!IVe+
} <%z/6I
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CountControl.java q
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/* 8VZ-`?p
* CountThread.java
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* p{rS -`I
* Created on 2007年1月1日, 下午4:57 .*j+?
* 2]+.8G7D%
* To change this template, choose Tools | Options and locate the template under -)oBh
* the Source Creation and Management node. Right-click the template and choose ,:`6x[ +
* Open. You can then make changes to the template in the Source Editor. '!R,)5l0h
*/ T?Y\~.+99
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package com.tot.count; U]|q4!WE
import tot.db.DBUtils; IfcFlXmt2
import java.sql.*; z m'jk D|
/** ! Cl/=0$[L
* ju#63
* @author RVfe}4Stm#
*/ `y`xk<q
public class CountControl{ L?0l1P
private static long lastExecuteTime=0;//上次更新时间 ~S3eatM$9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 \ax%I)3
/** Creates a new instance of CountThread */ V5B-S.i@
public CountControl() {} ))`Zv=y"
public synchronized void executeUpdate(){ @m V C
Connection conn=null; qN@a<row&~
PreparedStatement ps=null; o!~bR
try{ to3J@:V8e
conn = DBUtils.getConnection(); d<'xpdxc
conn.setAutoCommit(false); Wv"tAseu
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); kre&J
for(int i=0;i<CountCache.list.size();i++){ 2?QJh2
CountBean cb=(CountBean)CountCache.list.getFirst(); Q$1K{14I
CountCache.list.removeFirst(); PAHlj,n)
ps.setInt(1, cb.getCountId()); 0Mg8{
ps.executeUpdate();⑴ 3ZlI$r(
//ps.addBatch();⑵ >K
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} "NU".q
//int [] counts = ps.executeBatch();⑶ ?N*0S'dY
conn.commit(); c~xo@[NaS
}catch(Exception e){ !9,
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e.printStackTrace(); -`OR6jd
} finally{ 91H0mP>ki
try{ v=tj.Vg
if(ps!=null) { ozC!q)j
ps.clearParameters(); M N#C2 qz
ps.close(); `?JgHk
ps=null; ~7pjk
} kA__*b}8UK
}catch(SQLException e){} |Vi&f5p,@
DBUtils.closeConnection(conn); 4Umsc>yfK
} n*Vd<m;w
} +5[oY,^cO
public long getLast(){ ;YDF*~9u
return lastExecuteTime; hyiMOa
} v9U(sEDq
public void run(){ 6;cY!
long now = System.currentTimeMillis(); D a[C'm=
if ((now - lastExecuteTime) > executeSep) { N@6OQ:,[F
//System.out.print("lastExecuteTime:"+lastExecuteTime); Z=@)
//System.out.print(" now:"+now+"\n"); Jwd&[
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); d&uTiH? 0
lastExecuteTime=now; m> (h_j
executeUpdate(); .dT;T%3fO
} xGfDz*t
else{ 87KrSZ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {~fCqP.2
} Cc)P5\jh
} c1kxKxE
} ]<gCq/V #
//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 5xDN&su
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类写好了,下面是在JSP中如下调用。 O}_a3>1DY
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<% EWIc|b:
CountBean cb=new CountBean(); 3]<re{)J9O
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ;#s}b1
CountCache.add(cb); liqR#<
out.print(CountCache.list.size()+"<br>");
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CountControl c=new CountControl(); =5~F6to
c.run(); M~Qj'VVL
out.print(CountCache.list.size()+"<br>"); |90
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%>