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: l^B4.1rT
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CountBean.java \%.oi@A
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/* +`>E_+Mp
* CountData.java (C"q-0?n
* Xw<;)m
* Created on 2007年1月1日, 下午4:44 &=$f\O1Ty
* Dj'?12Onu=
* To change this template, choose Tools | Options and locate the template under A9u>bWIE7
* the Source Creation and Management node. Right-click the template and choose m)"(S
* Open. You can then make changes to the template in the Source Editor. @G=7A;-pv0
*/ A#19&}
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package com.tot.count; g,M-[o=Fk
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/** I"x|U[*B
* /j4G}
* @author Mx`';z8~
*/ rKI<!
public class CountBean { 6sQ;Z |!Pz
private String countType; gO"G/
int countId; z=g!mVK5
/** Creates a new instance of CountData */ Zv=pS
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public CountBean() {} $x]/|u/9
public void setCountType(String countTypes){ lNyyLLt
this.countType=countTypes; Ak('4j!*}^
} [u2t1^#Ol
public void setCountId(int countIds){ CI$z+zN
this.countId=countIds; q*`
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} qQG? k~r
public String getCountType(){ g52)/HM
return countType; JJSE@$",\
} C58o="L3S
public int getCountId(){ W|2| v?v
return countId; 7Re\*[)T
} ]4c+{
} .74C~{}$
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CountCache.java 0H^*VUyW/
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/* Lw_|o[I}
* CountCache.java Wkjp:`(-$r
* .Wy'
* Created on 2007年1月1日, 下午5:01 C~@m6K
* &Mudu/KTr
* To change this template, choose Tools | Options and locate the template under H)gc"aRe;Y
* the Source Creation and Management node. Right-click the template and choose 5|K[WvG@Co
* Open. You can then make changes to the template in the Source Editor. "G.X=,
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*/ U4K ZPk
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package com.tot.count; "0#(<zb|
import java.util.*; !bYVLFp=\_
/** Ry]9n.y
* QSa#}vCp*
* @author R2-F@_
*/ ckY#oRQ1
public class CountCache { {j]cL!Od
public static LinkedList list=new LinkedList(); GWPBP-)0
/** Creates a new instance of CountCache */ bo\Ah/.
public CountCache() {} $`/UG0rdC
public static void add(CountBean cb){ w?|qKO
if(cb!=null){ ;
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list.add(cb); SE^l`.U@
} :?g+\:`/0j
} d4\JM 65
} };9s8VZE
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CountControl.java iCg%$h
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/* E7? n'!=
* CountThread.java \ f+;X
* 'r%(,=L
* Created on 2007年1月1日, 下午4:57 7I"~a<f0X`
* 5o>`7(t`
* To change this template, choose Tools | Options and locate the template under rM
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* the Source Creation and Management node. Right-click the template and choose [w@S/K[_|
* Open. You can then make changes to the template in the Source Editor. GU2TQx{V
*/ C12V_)~2
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package com.tot.count; Q*ELMib
import tot.db.DBUtils; w->Y92q]
import java.sql.*; "49dsKIOH
/** *Ic^9njt
* UhS:tT]7
* @author z`E=V
*/ K2xHXziQ
public class CountControl{ XL.f`N.O
private static long lastExecuteTime=0;//上次更新时间 <iU@ M31
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 np6G~0Y`
/** Creates a new instance of CountThread */ 0,DrVGa
public CountControl() {} ^IuhHP
public synchronized void executeUpdate(){ {fHor
Connection conn=null; !s1<)%Jt
PreparedStatement ps=null; Qr~!YPK\
try{ r/ g{j
conn = DBUtils.getConnection(); jF}kV%E
conn.setAutoCommit(false); l~]] RgU
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); *(q?O_3,b
for(int i=0;i<CountCache.list.size();i++){ y _"V=:
CountBean cb=(CountBean)CountCache.list.getFirst(); ez[x8M>
CountCache.list.removeFirst(); {._'Q[
ps.setInt(1, cb.getCountId()); _%D7D~2r|
ps.executeUpdate();⑴ "%^_.Db>|
//ps.addBatch();⑵ [[AO6.Z
} B47 I?~{
//int [] counts = ps.executeBatch();⑶ o(Z~J}l({
conn.commit(); AkS16A
}catch(Exception e){ b:Zh|-
e.printStackTrace();
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} finally{ %?gG-R
try{ a"U3h[;$y
if(ps!=null) { -sJD:G,%
ps.clearParameters(); H<i!C|AF
ps.close(); E:**gvfq
ps=null; l5H5!$3~
} {X(nn.GpC
}catch(SQLException e){} v8y Cf7+"
DBUtils.closeConnection(conn); FD
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} g&2g>]
} L k
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public long getLast(){ Bt@?l]Y
return lastExecuteTime; zc)nDyn
} E#(e2Z=
public void run(){ 4uoZw3O
long now = System.currentTimeMillis(); QH(&Cu,
if ((now - lastExecuteTime) > executeSep) { ~s HdOMw
//System.out.print("lastExecuteTime:"+lastExecuteTime); b=MW;]F
//System.out.print(" now:"+now+"\n"); EDgtn)1
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); z[_Y,I
lastExecuteTime=now; ]i`Q+q[
executeUpdate(); C$+Q,guM
} }'x)e
else{ Z!|r>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); N^oP,^+U
} P`Ku.
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} Fh)xm* u(
} gF)-Ci
//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 `f~bnL
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类写好了,下面是在JSP中如下调用。 B;=Z^$%T
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<% *'8q?R?7g
CountBean cb=new CountBean(); dNt^lx
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |Vz)!M
CountCache.add(cb); ms}o[Z@n
out.print(CountCache.list.size()+"<br>"); \X*y~)+K`
CountControl c=new CountControl(); ">wvd*w0"(
c.run(); e7xv~C>g
out.print(CountCache.list.size()+"<br>"); o}KVT%}
%>