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: DG&
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CountBean.java MD(?Wh
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/* ovv<7`
* CountData.java rQ~7BlE
* O
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* Created on 2007年1月1日, 下午4:44 U5 X\RXy~
* z~[:@mGl
* To change this template, choose Tools | Options and locate the template under p<b//^
* the Source Creation and Management node. Right-click the template and choose ~JjL411pG
* Open. You can then make changes to the template in the Source Editor. *'5)CC
*/ *v1M^grKd
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package com.tot.count; DONXq]f:,"
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/** T(LqR?xOo
* p;;4b@
* @author s"u6po.'
*/ N?cvQR{r9
public class CountBean { 0#\K9|.
private String countType; e/+_tC$@p@
int countId; a]0B{
/** Creates a new instance of CountData */ ZAe'lgS
public CountBean() {} L=`QF'Im
public void setCountType(String countTypes){ 0,1x-
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this.countType=countTypes; O~3<P3W
} iBCZx>![;
public void setCountId(int countIds){ C\%T|ZDE
this.countId=countIds; yV{&x
} _ ~q!<-Z
public String getCountType(){ MW^(
return countType; N=Q<mj;,
}
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public int getCountId(){ 2xPkQOj3
return countId; Jo%`N#jG
} 9;W2zcN
} :P,g,
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CountCache.java ;Fo%R$y
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/* Z;=h=
* CountCache.java VT>TmfN(I
* .>QzM>zO
* Created on 2007年1月1日, 下午5:01 TJYup%q
* Lzr&Q(mL
* To change this template, choose Tools | Options and locate the template under `'W/uCpl
* the Source Creation and Management node. Right-click the template and choose =g.R?H8cj5
* Open. You can then make changes to the template in the Source Editor. C~e&J&zh
*/ ,=_)tX^
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package com.tot.count; PpXzWWU":
import java.util.*; s=S9y7i(R
/** EF>vu+YK
* }na0
* @author +N6IdDN3
*/ V8w7U:K
public class CountCache { rt rPRR\:"
public static LinkedList list=new LinkedList(); ='W=
/** Creates a new instance of CountCache */ 0Cg}yy Oz
public CountCache() {} #!0=I
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public static void add(CountBean cb){ <USK6!-G
if(cb!=null){ &nV/XLpG
list.add(cb); jj,CBNo(
} M2kvj'WWq
} '2S/FOb
} aM7e?.rU
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CountControl.java )_&P:;N
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/* _ez*dE%
* CountThread.java JRw<v4pZ
* CL|d>
* Created on 2007年1月1日, 下午4:57 ~|lEi1|
* q"48U.}T
* To change this template, choose Tools | Options and locate the template under a
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* the Source Creation and Management node. Right-click the template and choose 8|L U=p`y'
* Open. You can then make changes to the template in the Source Editor. SeV`RUO
*/ ptc.JB6
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package com.tot.count; HJi
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import tot.db.DBUtils; ,Y&7` m
import java.sql.*; *@VS^JB
/** en_W4\7^
* ]+k]Gbty6
* @author .rwa=IW
*/ pJ3-f k"i
public class CountControl{ /;5/7Bvj
private static long lastExecuteTime=0;//上次更新时间 cq`!17"k
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1`sTGNo
/** Creates a new instance of CountThread */ {/|tVc63
public CountControl() {} "C.cU
public synchronized void executeUpdate(){ aI\:7
Connection conn=null; }Ip1|Gj
PreparedStatement ps=null; :anR/
try{ Hmx
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conn = DBUtils.getConnection(); =E$B0^_2RC
conn.setAutoCommit(false); >g;995tG
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); NI:3hfs
for(int i=0;i<CountCache.list.size();i++){ *7w,o?l
CountBean cb=(CountBean)CountCache.list.getFirst(); RhWW61!"
CountCache.list.removeFirst(); [#SiwhF|
ps.setInt(1, cb.getCountId()); U+Vb#U7;
ps.executeUpdate();⑴ M1q_gHA
//ps.addBatch();⑵ sd _DG8V
} aF{1V\e
//int [] counts = ps.executeBatch();⑶ 0iV~MQZ(
conn.commit(); c
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}catch(Exception e){ (j-_iOQ]i+
e.printStackTrace(); 3Ct:AJeg
} finally{ FOAXm4"
try{ 3ESrd"W=
if(ps!=null) { [ <j4w
ps.clearParameters(); Os/?iGlD*E
ps.close(); @e-2]z
ps=null; } 4ZWAzH
} =u`tlN5pOT
}catch(SQLException e){} fizL_`uMqb
DBUtils.closeConnection(conn); +}
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} y7Nd3\v [\
} Khh}flRy
public long getLast(){ C;%1XFzM
return lastExecuteTime; C[,&Y&`j
} \cdns;
public void run(){ G8.nKoHv7x
long now = System.currentTimeMillis(); -6xh
if ((now - lastExecuteTime) > executeSep) { |zJ2ZE|
//System.out.print("lastExecuteTime:"+lastExecuteTime); oS~;>]W
//System.out.print(" now:"+now+"\n"); Wjli(sT#-
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); <rFh93
lastExecuteTime=now; 1/v#Z#3[
executeUpdate(); ~|S}$|Mi50
} 7b7WQ 7u
else{ A@eR~Kp
^
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); lHFk~Qp[
} AzVv-!Y
} "-P z2QJY
} pjma<^|F
//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 C%|m[,Gx
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类写好了,下面是在JSP中如下调用。 fVJWW):
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<% /I:&P Pff
CountBean cb=new CountBean(); i]Bu7Fuu
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Yq'D-$@
CountCache.add(cb); vSY
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out.print(CountCache.list.size()+"<br>"); o+Mc%O Z
CountControl c=new CountControl(); $}fY
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c.run(); agq4Zy
out.print(CountCache.list.size()+"<br>"); :x3xeVtY
%>