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: 2WYPO"q
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CountBean.java }U5yQ%N
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/* %sQ^.` 2
* CountData.java e6RPIg
* C8i^P}y
* Created on 2007年1月1日, 下午4:44 G+\GaY[
* *$ %a:q1U
* To change this template, choose Tools | Options and locate the template under UByv?KZi
* the Source Creation and Management node. Right-click the template and choose cDH^\-z
* Open. You can then make changes to the template in the Source Editor. qPfQy
*/ TT3|/zwn
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package com.tot.count; mF^v ~
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/** %&t<K3&Yh
* ,7K`[
* @author wz ~d(a#
*/ PBkt~=j
public class CountBean { O]1(FWYy
private String countType; tT?cBg{
int countId; vn"{I&L+w0
/** Creates a new instance of CountData */ (0y~%J
public CountBean() {} WlBc.kFck
public void setCountType(String countTypes){ s#=7IH30
this.countType=countTypes; m5Di=8
} ]}2ZttQ?
public void setCountId(int countIds){ '}bgLv
this.countId=countIds; ;cN{a&
} x>`%DwoRI
public String getCountType(){ t" Z6[XG
return countType; l3F6AlPql
} Jz
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public int getCountId(){ \7'{g@C(
return countId; $43qME
} &m:uO^-D
} /{--+
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CountCache.java <1\Nb{5
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/* "d5n \@[t
* CountCache.java o"R7,N0rB
* LW_f
* Created on 2007年1月1日, 下午5:01 ?R.j^S^
* @A^;jk
* To change this template, choose Tools | Options and locate the template under k-OPU,
* the Source Creation and Management node. Right-click the template and choose =xx]@
* Open. You can then make changes to the template in the Source Editor. 'qX|jtdM
*/ ..'_o~Ka
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package com.tot.count; z]D69O b
import java.util.*; FZE"7ec>m
/** Jcm&RI"{
* JQHvz9Yg
* @author SPmq4
*/ eb"5-0
public class CountCache { mmRJ9OhS
public static LinkedList list=new LinkedList(); =k`Cr0aPF
/** Creates a new instance of CountCache */ uw+M
public CountCache() {} Qe0lBR?H
public static void add(CountBean cb){ d-r@E3
if(cb!=null){ ocS5SB]8
list.add(cb); \<TXS)w]
} G..aiA
} @eIJ]p
} r/6o \-
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CountControl.java +@k+2?]
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/* ' x35=@
* CountThread.java !s?nJ(p
* !6>~?gNd
* Created on 2007年1月1日, 下午4:57 Hm'=aff6A
* O]Qd<%V'x
* To change this template, choose Tools | Options and locate the template under 3Xy-r=N. l
* the Source Creation and Management node. Right-click the template and choose en*GM}<V
* Open. You can then make changes to the template in the Source Editor. /F'sb[
*/ 4s{~r
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package com.tot.count; 9b"=9y,
import tot.db.DBUtils; 9=h'9Wo
import java.sql.*; l &5QZI0I
/** v"XGC i91L
* Ayw ;N
* @author fbKkq.w
*/ !1{e|p
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public class CountControl{ q0R -7O(
private static long lastExecuteTime=0;//上次更新时间 EkNunCls
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @?
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/** Creates a new instance of CountThread */ nWYN Np?h
public CountControl() {} E`de7
public synchronized void executeUpdate(){ [dIXR
Connection conn=null; !1 8clL
PreparedStatement ps=null; aa#Y=%^
try{ Jx7C'~,J
conn = DBUtils.getConnection(); H0`]V6+<f
conn.setAutoCommit(false); -0{r>,&Mm
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 8sTp`}54J
for(int i=0;i<CountCache.list.size();i++){ 9V@V6TvW>&
CountBean cb=(CountBean)CountCache.list.getFirst(); G5aieD.#
CountCache.list.removeFirst(); K<qk.~
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ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ q[W
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//ps.addBatch();⑵ Q&=w_Wc
} jun_QiU:2
//int [] counts = ps.executeBatch();⑶ 1A G<$d5U|
conn.commit(); $ig0j`
}catch(Exception e){ DiwxXqY
e.printStackTrace(); T)TfB(
} finally{ 6BbGA*%{
try{ |G,tlchprs
if(ps!=null) { "(z5{z?S
ps.clearParameters(); .e=:RkI,
ps.close(); ADP%QTdqFJ
ps=null; L`p4->C9A
} @As[k2
}catch(SQLException e){} *%fi/bimG
DBUtils.closeConnection(conn); v>Yb/{A
} vK\%%H
} Y^7$t^&
public long getLast(){ !1DKLQ
return lastExecuteTime; =JbRu|/
} dq&yf7
public void run(){ vAh6+K.e
long now = System.currentTimeMillis(); ,3p~w5C/+[
if ((now - lastExecuteTime) > executeSep) { BJsz2t :0
//System.out.print("lastExecuteTime:"+lastExecuteTime); W;L7SF g)
//System.out.print(" now:"+now+"\n"); C|).;V&
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1&)?JZhg
lastExecuteTime=now; nvJf/90$
executeUpdate(); ]?+p5;{y4
} !K}~/9Z=m
else{ JedmaY06=
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); L>9V&\
} 8WbgSY`
} f'-i o<.
} F6OpN"UM'
//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 E2@65b$
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类写好了,下面是在JSP中如下调用。 dzsmIV+
v7jq@#-
<% P&)xz7wG
CountBean cb=new CountBean(); 1H@>/QC
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +"cq(Y@
CountCache.add(cb); (k) l=]`}
out.print(CountCache.list.size()+"<br>"); o-{[|/)Tk
CountControl c=new CountControl(); Ov4y%Pj
c.run(); o(
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out.print(CountCache.list.size()+"<br>"); =/Mq 5.
%>