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: i;/;zG^=_
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CountBean.java Pzd!"Gl9
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/* ~`Vo0Z*S
* CountData.java 6:8Nz
* z79oj\&[
* Created on 2007年1月1日, 下午4:44 55TFBDc
* I(kEvfxc"
* To change this template, choose Tools | Options and locate the template under k,'MmAz
* the Source Creation and Management node. Right-click the template and choose ,Xn%0]
* Open. You can then make changes to the template in the Source Editor. W5Jy"]^I
*/ _<2{8>EVf
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package com.tot.count; 5+Tx01)
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/** /E{tNd^S
* pRxVsOb
* @author G#f3
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*/ .}eM"Kv
public class CountBean { 5]CaWFSmT
private String countType; #H
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int countId; {*g{9`
/** Creates a new instance of CountData */ M&q~e@P
public CountBean() {} I*JJvqh
public void setCountType(String countTypes){ (nBh6u*
this.countType=countTypes; #PPHxh*S
} H/ Ql
public void setCountId(int countIds){ P*}aeu&lnD
this.countId=countIds; Y`$\o
} 7I]?:%8h
public String getCountType(){ pmurG
return countType; 2!CL8hG5:
} hMvJNI6O
public int getCountId(){ ^
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return countId; "|Y y"iB[
} Wlq3r#
} /zQx}U)TP
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CountCache.java u0)9IZxc
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/* 3fX_XH1Q
* CountCache.java IZ^:wIKo{
* ,!,M'<?"
* Created on 2007年1月1日, 下午5:01 lt]&o0>
* 2ve<1+V_
* To change this template, choose Tools | Options and locate the template under xX{Zh;M&[
* the Source Creation and Management node. Right-click the template and choose `m#G'E I
* Open. You can then make changes to the template in the Source Editor. zLg$|@E&
*/ o
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package com.tot.count; 4T]n64Yid
import java.util.*; fT:a{
/** _]g?3Gw7!
* 1:L _qL
* @author z?9vbx
*/ 5*Wo/%#q
public class CountCache { @'
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public static LinkedList list=new LinkedList(); vMDX
/** Creates a new instance of CountCache */ GIo7-
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public CountCache() {} rKK{*%n
public static void add(CountBean cb){ x<mHTh:-V
if(cb!=null){ 3,Dc}$t
list.add(cb); 8IX:XDEQ
} nPAVrDg
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} h3}gg@Fm
} %Ls5:Z=
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CountControl.java **].d;~[l
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/* \(S69@f
* CountThread.java =\t%U5
* sYt\3/yL'
* Created on 2007年1月1日, 下午4:57 V3^=Mj2"
* e@Cv')]B
* To change this template, choose Tools | Options and locate the template under Nb[zm|.
* the Source Creation and Management node. Right-click the template and choose Z= 'DV1A$,
* Open. You can then make changes to the template in the Source Editor. yu<'-)T.?
*/ ,wyfMOGLt
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package com.tot.count; CG`s@5y>5
import tot.db.DBUtils; `{1&*4!
import java.sql.*; 9;fyC=
/** P|:*OM
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* H(MCY3t
* @author x]1G u
*/ J ejDF*Q
public class CountControl{ Z~JX@s0v
private static long lastExecuteTime=0;//上次更新时间 U}6FB =
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *@E Itj `
/** Creates a new instance of CountThread */ b1("(,r/`
public CountControl() {} *%{
public synchronized void executeUpdate(){ p1-bq:
Connection conn=null; )]\?Yyg]
PreparedStatement ps=null; vf|lF9@U
try{ )ZyEn%
conn = DBUtils.getConnection(); xh7[{n[;
conn.setAutoCommit(false); ftL>oOz[
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 0v~Eu>Rg
for(int i=0;i<CountCache.list.size();i++){ Oq7R^t`b
CountBean cb=(CountBean)CountCache.list.getFirst(); h1y6`m9
CountCache.list.removeFirst(); rO_|_nV[
ps.setInt(1, cb.getCountId()); ]m>N!Iu
ps.executeUpdate();⑴ ZPM,ZGlu:
//ps.addBatch();⑵ T:/68b*H\:
} j:JM v
//int [] counts = ps.executeBatch();⑶ sRM3G]nUr
conn.commit(); *=6,}rX"I
}catch(Exception e){ M~6x&|2
e.printStackTrace(); eH*u,/
} finally{ CL~21aslI
try{ qtx5N)J6
if(ps!=null) { |5ifgSZ
ps.clearParameters(); k:+Bex$g
ps.close(); #^\qFj
ps=null; Ar+<n 2;[
} +npcU:(Kg
}catch(SQLException e){} c|kQ3(
DBUtils.closeConnection(conn); i$Rlb5RU
} +
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} Y|s?9'z
public long getLast(){ S`!MoIMsD
return lastExecuteTime; Oy @vh>RY
} nvJ2V$
public void run(){ ]^='aQ
long now = System.currentTimeMillis(); l c<&f
if ((now - lastExecuteTime) > executeSep) { A[,[j?wC
//System.out.print("lastExecuteTime:"+lastExecuteTime); N+<`Er
//System.out.print(" now:"+now+"\n"); OT&mNE4
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 12NV
lastExecuteTime=now; tRqg')y
executeUpdate(); `kx+ Kc
} [M^ur%H
else{ w
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 9Q!X~L|\S
} :&]THUw
} uq}>5
} Hkc:B/6
//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 n..9F$a
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类写好了,下面是在JSP中如下调用。 1I#S?RSb
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<% 4_`ss+gk
CountBean cb=new CountBean(); ([-xM%BI6
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); (I bT5
CountCache.add(cb); ]FJpe^
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out.print(CountCache.list.size()+"<br>"); =uZOpeviQ
CountControl c=new CountControl(); Z/z(P8#U\
c.run(); 67uUeCW
out.print(CountCache.list.size()+"<br>"); a\wpJ|3{=T
%>