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: >XPR)&t
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CountBean.java oS^g "hQ`\
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/* F/ui(4
* CountData.java BG_6$9y
* ]]9VI0
* Created on 2007年1月1日, 下午4:44 W4q
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* Hq
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* To change this template, choose Tools | Options and locate the template under Ij2Th]
* the Source Creation and Management node. Right-click the template and choose \ 0/m$V.
* Open. You can then make changes to the template in the Source Editor. 3?Fe(!@
*/ #H;1)G(/
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package com.tot.count; L~("C
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/** snP]&l+
* 2(km]H^
* @author I#/"6%e
*/ Yy0U2N[i
public class CountBean { t1ers> h
private String countType; XwIhD
int countId;
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/** Creates a new instance of CountData */ NtNCt;_R7
public CountBean() {} k>F>y|m
public void setCountType(String countTypes){ \3T[Cy|5|
this.countType=countTypes; /^$n&gI
} PQ 2rNY6
public void setCountId(int countIds){ v;#0h7qd
this.countId=countIds; bFVY&
} qRL45[ K
public String getCountType(){ MIY`"h0*
return countType; -oi@1g@
} .UYhj8
public int getCountId(){ =g |5VXW5
return countId; qOflvf
} S2
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} N<XMSt
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CountCache.java ^t?vv;@}
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/* gI00@p:m
* CountCache.java 9^E!2CJ
* )cU$I)
* Created on 2007年1月1日, 下午5:01 w\a6ga!xt"
* 5[]Yx l
* To change this template, choose Tools | Options and locate the template under 5!BW!-q
* the Source Creation and Management node. Right-click the template and choose Fg0!2MKq*
* Open. You can then make changes to the template in the Source Editor. d^8n
*/ NInZ~4:
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package com.tot.count; W9;9\k
import java.util.*; S@Aw1i p
/** Z|xgZG{
* kAs=5_?I
* @author ]IH1_?HgP7
*/ <vt}+uMzXv
public class CountCache { 8x-(7[#e<g
public static LinkedList list=new LinkedList(); j!"5,~
/** Creates a new instance of CountCache */ <8^ws90Y
public CountCache() {} 5p ,HkV
public static void add(CountBean cb){ F{Oaxn
if(cb!=null){ [WI'oy
list.add(cb);
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} ccT
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} wli H3vA_
} yIg^iZD
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CountControl.java u/ri
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/* ?kS#g
* CountThread.java `A<2wd;
* X6=o vm
* Created on 2007年1月1日, 下午4:57 LTuT"}dT[
* c4.2o<(Xt
* To change this template, choose Tools | Options and locate the template under {s{+MbD
* the Source Creation and Management node. Right-click the template and choose pTT00`R
* Open. You can then make changes to the template in the Source Editor. N~P1^x~
*/ :q~5Xw/
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package com.tot.count; FSkLR h
import tot.db.DBUtils; `6(Zc"/
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import java.sql.*; yd[4l%G(zS
/** j /@<=
* $4Dr +Z
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* @author Z29LtKr
*/ ! F<::fN
public class CountControl{ 7g:Lj,Z4L
private static long lastExecuteTime=0;//上次更新时间 ez~u A4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 IaKJ W?
/** Creates a new instance of CountThread */ s1t kiX{>
public CountControl() {} dptfIBYc+
public synchronized void executeUpdate(){ !x!1H5"
Connection conn=null; OIkjO}/7
PreparedStatement ps=null; K"ly\$F
try{ @>&b&uj7T
conn = DBUtils.getConnection(); /qFY$vj
conn.setAutoCommit(false); = ?BhtW
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); E{}J-_oS45
for(int i=0;i<CountCache.list.size();i++){ ^Jw=5ImG
CountBean cb=(CountBean)CountCache.list.getFirst(); t{,e{oZx
CountCache.list.removeFirst(); pu_?)U
ps.setInt(1, cb.getCountId()); ]x(6^:D5
ps.executeUpdate();⑴ Dl,sl>{
//ps.addBatch();⑵ NKTy!zWh
} w`v`aw]
//int [] counts = ps.executeBatch();⑶ 6Hfv'X5E`Z
conn.commit(); V+r&Z<&
}catch(Exception e){ |T]&8Q)S
e.printStackTrace(); 4*inN~cU
} finally{ C~pQJ@bF0
try{ nm_4E8&X
if(ps!=null) { ^=8/I w
ps.clearParameters(); 0O>M/ *W
ps.close(); QEMT'Cs
ps=null; n5)ml)m
} ]wfY<Z
}catch(SQLException e){} 9_8\xLk
DBUtils.closeConnection(conn); =R ZPDu
} ZXXJ!9-&+J
} g yegdky3
public long getLast(){ ryqu2>(
return lastExecuteTime; ;j
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} ~NLthZ(O
public void run(){ ?zfm"o
long now = System.currentTimeMillis(); KK{_s=t%<
if ((now - lastExecuteTime) > executeSep) { lM#,i\8Q
//System.out.print("lastExecuteTime:"+lastExecuteTime); o ZQ@ Yu3
//System.out.print(" now:"+now+"\n"); ym_as8A*Q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 7 U-}Y
lastExecuteTime=now; X&i;WI
executeUpdate(); PjXiYc&
} OUFy=5(%:
else{ G6lC[eK
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Xk1uCVUe5
} #l@P}sHXq
} 'z{|#zd9
} w#ZzmO
//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 r4<As` &
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类写好了,下面是在JSP中如下调用。 ,*YmXR-"
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<% FM(EOsWk
CountBean cb=new CountBean(); IZiS3
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); G/#m.=t
CountCache.add(cb); Vbe@S?u-
out.print(CountCache.list.size()+"<br>"); j@Pd"
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CountControl c=new CountControl(); 7GS4gSd3
c.run(); 1hSV/%v_
out.print(CountCache.list.size()+"<br>"); PKC0Dt;F.
%>